MLS User’s Guide Watlow Controls 1241 Bundy Blvd. Winona, MN 55987 Customer Service Phone: (800) 414-4299 Fax: (800) 445-8992 Technical Support Phone: (507) 494-5656 Fax: (507) 452-4507 Email: wintechsupport@watlow.com Part No. 11570-00. Revision 3.
Copyright © 1995 Watlow-Anafaze Information in this manual is subject to change without notice. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form without written permission from Watlow-Anafaze. Warranty Watlow-Anafaze, Incorporated warrants that the products furnished under this Agreement will be free from defects in material and workmanship for a period of one year from the date of shipment.
Addendum for MLS User’s Guide (3.6) Addendum for MLS User’s Guide (3.6) The following are changes to revision 3.6 of the MLS User’s Guide. The changes pertain to a new power supply that is being used with the MLS. All changes are listed below by page number. Shaded portions refer to the actual changed text. These changes will be incorporated in the next manual revision. System Power Requirements (from page 10) MLS-PM supply input 10-28 Vdc at <1 amp MLS-AIM supply input 4.75 to 5.25 Vdc at <0.
Addendum for MLS User’s Guide (3.6) Mounting the MLS-PS (from page 23) Follow these instructions to mount the MLS-PS. If you use your own power supply for the MLS, please refer to the power supply manufacturer's instructions for mounting information. Choose a power supply that supplies a regulated 10 to 28 Vdc at 1 watt, and isolated return line. Mounting Environment The MLS-PS measures 1.40" x 8" x 3.9". Leave enough clearance around the power supply that you can remove it later.
Addendum for MLS User’s Guide (3.6) Wiring Your System (from page 24) This section explains how to wire the components of your system. Below is the system connections diagram reprinted here for your convenience. (See the next page for wiring instructions.) MLS User’s Guide (11570-00 rev. 3.
Addendum for MLS User’s Guide (3.6) Wiring Recommendations (from page 25) This section gives general wiring recommendations. WARNING Never wire bundles of low power Watlow-Anafaze circuits next to bundles of high power AC wiring. Instead, physically separate high power circuits from the controller. If possible, install high voltage AC power circuits in a separate panel. • Use stranded wire. (Use solid wire for fixed service; it makes intermittent connections when you move it for maintenance.
Contents Overview .....................................................................1 System Diagram.................................................................. 2 Parts List .. .......................................................................... 2 Safety ....... .......................................................................... 3 Introduction................................................................5 Specifications................................................................
Contents MLS User’s Guide Connecting Power and RTB to MLS-PM..................... 27 Connecting Power and Common to AIM-TB............... 28 Testing Connections ..................................................... 28 Testing Your System .......................................................... 30 MLS-AIM Test ............................................................. 30 RTB Test....................................................................... 30 PID Output Test .................................
MLS User’s Guide Contents Job Digital Input Polarity.............................................. 64 Output Override Digital Input....................................... 64 Output Override Input Polarity ..................................... 64 Startup Alarm Delay ..................................................... 65 Keyboard Lock Status................................................... 65 Power-Up Output Status ............................................... 65 Controller Address ...................
Contents MLS User’s Guide Heat/Cool Output Override........................................... 85 Heat/Cool Nonlinear Output Curve .............................. 86 Setup Loop Alarms ............................................................. 87 Alarm Types ................................................................ 88 Alarm Delay.................................................................. 90 High Process Alarm Setpoint........................................ 91 High Process Alarm Type.......
MLS User’s Guide Contents Troubleshooting Stand-Alone Systems .............................. 110 MLS-PM Has No Power............................................... 110 Keys Don't Respond...................................................... 111 Controller Message: AIM Comm Failure ..................... 111 Checking Analog Inputs ............................................... 111 Checking PID Control Outputs..................................... 112 Checking Digital I/O.....................................
Contents vi MLS User’s Guide
Overview Overview This manual describes how to install, setup, and operate a 16 or 32 MLS controller. Included are seven chapters and a glossary of terms. Each chapter covers a different aspect of your control system and may apply to different users. The following describes the chapters and their purpose. • Introduction: Gives a general description of the MLS and its related specifications. • Installation: Describes how to install the MLS and its peripheral devices.
Overview System Diagram The illustration below shows how the parts of the MLS are connected. When unpacking your system, use the diagram and parts list below to ensure all parts have been shipped. Please don't hesitate to call WatlowAnafaze's Technical Service Department if you have problems with your shipment, or if the MLS' components are missing or damaged. Parts List • MLS Processor Module (PM) • Controller Mounting Kit • MLS AIM Module (16 or 32) • AIM Cable, 4 foot.
Overview Safety Watlow-Anafaze has made efforts to ensure the reliability and safety of the MLS™ Controller and to recommend safe usage practices in systems applications. Please note that, in any application, failures can occur. These failures may result in full control outputs or other outputs which may cause damage to or unsafe conditions in the equipment or process connected to the MLS Controller.
Overview 4 MLS User’s Guide
Introduction Introduction The MLS is a modular control system with 32 fully independent loops of PID control. It can function as a stand-alone controller; the MLS processor module's 1/8 DIN front panel has a Liquid Crystal Display (LCD) and touch keypad for local display and local parameter entry. You can also use it as the key element in a computer-supervised data acquisition and control system; the MLS can be locally or remotely controlled via an RS-232 or RS-485 serial communications interface.
Introduction Front Panel or Computer Operation: You can set up and run the MLS Controller from the processor module's front panel or from a local or remote computer. Watlow-Anafaze offers ANASOFT, our IBM-AT or IBM-PC compatible software you can use to operate the MLS.
Introduction Specifications This section shows specifications for the MLS, including inputs, outputs, serial interface information, system power requirements, and environmental and physical specifications. Analog Inputs Number of control loops 16 dual output or 32 single output plus one pulse loop. Number of analog inputs 16 (with AIM-16) or 32 (with AIM-32). Input switching Differential solid state MUX switching. Input sampling rate 16 loops per second.
Introduction RTD Ranges RTD1 -148.0 to 572°F (-100.0 to 300.0°C) 0.1°C RTD2 -184 to 1544°F (-120 to 840°C) 1.0°C RTD3 -94 to 572°F (-70 to 300°C) 1.0°C Miscellaneous Specifications T/C break detection Pulse type for upscale break detection and thermocouple alarm display. Milliamp inputs 0-10 mA, 0-20 mA (4-20 mA), etc., with scaling resistors. Infrared inputs power supply included, with scaling resistors for IRSM.
Introduction Digital Outputs Standard Digital Outputs Number 34 continuous 10 mA sink referenced to +5 Vdc of MLS for SSR operation; 20 mA momentary peak sink. User selectable outputs 34 PID control, Alarm/control, or Events. Two outputs are not PID programmable. Number of PID loops 16 or 32 programmable loops. 16-loop systems have dual outputs. 32-loop systems have 32 single outputs, and you can individually configure outputs 17-32 as a second outputs for loops 1-16.
Introduction Miscellaneous Specifications Serial Interface Type RS-232 3-wire or RS-485 4-wire. Isolation RS-232: None RS-485: To EIA RS-485 specification. Baud Rate 2400 or 9600, user selectable. Error Check BCC or CRC, user selectable. Number of Controllers 1 with RS-232 communications, 32 with RS-485 communications, 16 with open frame units. Protocol Form of ANSI X3.28-1976, (D1, F1) compatible with Allen-Bradley PLC, full duplex.
Introduction Expanded Parts List The Expanded Parts List contains a technical description of each component of your MLS Controller. MLS Processor Module Technical Description The MLS Processor Module (MLS-PM) is housed in an eighth-DIN panel mount package. It contains the power supply circuits, the CPU, RAM with a built-in lithium battery socket, EPROM, serial communications, digital I/O, and the LCD screen and touch keypad.
Introduction The eight digital inputs are referenced to the MLS controller common; an open input pulls them High (Off). When you short the input to controller common the input goes Low (On). Do not connect external power sources to the MLS' digital inputs. Front Panel Description The MLS-PM's panel mounted LCD screen and touch keypad provide an intelligent way to operate the MLS. The on-board display driver operates the liquid crystal display.
Introduction The RTB is a screw terminal interface for control wiring which allows you to easily connect external "real world" wiring to the MLS. The RTB connects a 50-pin flat ribbon cable to a screw terminal block which accepts #18 or #20 AWG wires. The ribbon cable receptacle has a locking latch which keeps the cable in place. The RTB's 34 digital outputs are sink outputs referenced to the +5 Vdc power supply of the MLS Controller. They are Low when the output is On.
Introduction Here's a picture of the MLS-AIM-32 and terminal block: MLS Cabling Technical Description Watlow-Anafaze provides all the cables required to install your MLS. The 50 pin ribbon cable which connects the RTB to the MLS-PM is an 0.05 space conductor-zoned 50 pin cable. Pin #1 is at the red edge of the cable. The cables which connect the MLS-PM to the AIM-TB, the optional Smart I/O Module (SIOM) and the computer are 6-conductor shielded cable.
Installation Installation These installation instructions are written for nontechnical users. If you are an electrician or you are technically proficient, they may seem simple to you. Please at least skim all of the instructions, to make sure you don't miss anything vital. (If you have installed a Modular Loop System before, you may wish to use the Quick Start foldout to install this system.) This section explains installation for the MLS Controller only.
Installation Read This Before Installation WARNING During installation and wiring, place temporary covers over the housing slots and the rear of the MLS so dirt and pieces of wire don't fall through the slots. When you are finished with installation, remove the covers. Install the MLS so the airflow to the slots in the housing is not restricted after installation. Make sure that other equipment does not block airflow to the housing slots. Use #18 or #20 AWG wires and trim wire insulation to 1/4" (5 mm).
Installation Recommended Tools This section lists the tools you will need to install the MLS Controller. Panel Hole Cutters Use any of these tools to cut a hole in the panel: • A jigsaw and metal file--for stainless steel and other heavyweight panel doors. • A Greenlee 1/8 DIN rectangular punch (Greenlee part #600-68)--for most panel materials or thicknesses. • A nibbler and metal file--for aluminum and other lightweight panel doors.
Installation Mounting the MLS-PM This section tells you how to mount the MLS-PM. NOTE Mount the MLS-PM before you mount any other component of the MLS. The processor module's placement affects placement and wiring for the MLS-AIM, MLS-PS, etc. Mounting Environment Install the MLS-PM in a location free from excessive (>50 ºC) heat, dust, and unauthorized handling. The MLS-PM's 1/8 DIN package can mount in panels up to 0.2" thick. Its dimensions are 1.89" x 3.78" x 6.1" (48 x 96 x 156 mm), as shown below.
Installation MLS-PM Mounting Steps 1. Use the template below to cut a hole in the panel. Be careful; the 0.02" (0.5 mm) tolerances don't allow much room for error. Use a punch, nibbler, or jigsaw; file the edges of the hole. WARNING Make sure bits of wire and debris do not lodge in the electronics, or else make sure you clean the electronics before you connect power. 2. Insert the MLS-PM into the hole through the front of the panel. 3. Screw the top and bottom clips in place.
Installation Mounting the MLS-AIM This section contains mounting instructions and diagrams for the MLSAIM. NOTE If you plan to install scaling resistors, mount them on the AIM-TB before you mount the AIM-TB in the panel. (If you mount the AIM-TB in the panel before you mount the scaling resistors on it, you will have to remove the AIM-TB from the panel to install the scaling resistors.) If you ordered an MLS-AIM-TB with scaling inputs from Watlow-Anafaze, the scaling resistors are already installed.
Installation Scaling Resisters AIM Communications Port (Tel. 1) Mounting Holes Mounting Steps 1. Choose an appropriate place to install the MLS-AIM. 2. Place the MLS-AIM where you will mount it and use a pencil to trace around the plastic standoffs on the AIM. (If you wish, you can use the AIM mounting template in the Quick Start foldout to position the holes.) 3. Drill four #6 or #8 holes in the chosen location. (#8 holes provide more clearance.) 4. Place the MLS-AIM where you will mount it.
Installation Mounting the RTB To mount the RTB, slide it onto a DIN rail. Watlow-Anafaze recommends Phoenix Contact’s NS32 perforated DIN rail (part number 12-01-00-2). Mount the DIN rail according to Phoenix Contact’s instructions and slide the RTB onto it. WARNING Do not connect power to the MLS now. Test the unit first, as explained in the Power Wiring and Controller Test section.
Installation Mounting the MLS-PS Follow these instructions to mount the MLS-PS. If you use your own power supply for the MLS, please refer to the power supply manufacturer's instructions for mounting information. Choose a power supply that supplies a regulated 7-28 Vdc at 1 watt, and isolated return line. Mounting Environment The MLS-PS measures 1.75" x 8" x 5". Leave enough clearance around the power supply that you can remove it later. Mounting Steps The MLS-PS has a bracket at each end of the unit.
Installation Wiring Your System This section explains how to wire the components of your system. Below is the system connections diagram reprinted here for your convenience. (See the next page for wiring instructions.
Installation Wiring Recommendations This section gives general wiring recommendations. DANGER Never wire bundles of low power Watlow-Anafaze circuits next to bundles of high power AC wiring. Instead, physically separate high power circuits from the controller. If possible, install high voltage AC power circuits in a separate panel. • Use stranded wire. (Use solid wire for fixed service; it makes intermittent connections when you move it for maintenance.) • Use #18 or #20 AWG wire.
Installation Cable Recommendations Use these cables or their equivalent. Function MFR P/N No. of Wires AWG Analog Inputs Belden #9154 Belden #8451 2 2 20 22 RTD Inputs Belden #8772 Belden #9770 3 3 20 22 T/C Inputs T/C Ext.
Installation If you must use EM relays and you must place them in a panel with Watlow-Anafaze equipment, use a .01 microfarad capacitor rated at 1000 Vac (or higher) in series with a 47 ohm, ½ watt resistor across the normally open (NO) contacts of the relay load. This network is known as an arc suppressor or snubber network. You can use other voltage suppression devices, but they are not usually required.
Installation 3. Plug the AIM communications cable into the slot on the MLS-PM labeled "To AIM". 4. Plug the other end of the AIM communications cable into the slot on the MLS-AIM labeled "Tel 1". (The slot is on top of the V/F card.) WARNING Do not turn on the AC power now. Test the connections first, as explained below. 5. Connect AC power wires to the MLS-PS. 6. Connect " " terminal on MLS AIM to frame Ground.
Installation • Turn the power back on. The Processor Module's display should light up, and after about a second the Bar Graph display should appear, followed by the message "AIM COMM FAIL". 5. Connect the Common lead of the voltmeter to TB3 and the power lead of the voltmeter to the AIM-TB terminal labeled "+5V". The voltage on the "+5V" terminal should be between +4.75 and +5.25 Vdc. 6. If the voltages are within the limits described above: A. Turn off the power. B.
Installation Testing Your System This section explains how to test the controller after installation. MLS-AIM Test Use this procedure to test the MLS-AIM before you connect inputs to it. 1. Connect a wire from the A+ terminal for loop 1 to the A- terminal for loop 1. 2. Turn on power to the MLS-PM. 3. Press the ALARM ACK key to clear the alarm messages displayed on the MLS-PM's screen. 4. Press the YES key to reach the single loop display for Loop 1.
Installation NOTE Your MLS is shipped with heat outputs enabled and cool outputs disabled. You can disable any PID output and use it for other digital output functions. All digital outputs and PID outputs are sink outputs referenced to the 5Vdc supply. These outputs are Low when they are On. All digital inputs are Transistor-Transistor Logic (TTL) level inputs referenced to control common. Outputs This section discusses the MLS' PID control and alarm outputs.
Installation Ribbon Cable Recommendations Use the 50-pin connector for both ends of the 50 pin flat ribbon cable. (Do not connect either end to a screw terminal; the cable wire is too small to withstand much flexing.) Do not exceed 15' of 50-conductor cable. Using the Cable Tie Wraps When you have wired outputs to the TB-50, install the cable tie wraps shipped with it. This diagram shows the cable tie wrap holes. Each row of terminals has a cable tie wrap hole at one end.
Installation PID Control and Alarm Output Connections Typical digital control outputs use external optically-isolated solid-state relays (SSRs). The SSRs use a 3 to 32 Vdc input for control, and you can size them to switch up to 100 amps at 480 Vac. For larger currents, use these optically-isolated relays to drive contactors. NOTE Control outputs are sink outputs. They are Low when the output is On. Connect them to the negative side of Solid State Relays.
Installation RTB Connections Connect outputs to the RTB as shown in the table below.
Installation AIM Communications Failure The controller continuously checks communications between the MLSPM and the AIM. If communication stops for more than five seconds, the MLS-PM display indicates AIM COMM FAIL, the PID mode changes to manual, and the controller sets every output to the output override percentage. WARNING PID outputs remain in manual mode after an AIM communications failure. After an AIM failure, change the PID control status back to automatic mode for each control loop.
Installation Inputs This figure shows the AIM cards (also known as the MUX cards) and AIM-TB, with scaling resistor locations. Scaling Resisters AIM Communications Port (Tel. 1) • The loop input number is marked on the terminal block: the number 1 indicates an input for loop 1, the number 2 an input for loop 2, etc. • The A+ terminal is the positive input of the analog signal. • The A- terminal is the negative input of the analog signal.
Installation • The A COM (AUX) terminal is the Auxiliary input. This is analog common used for RTD inputs. WARNING Do not exceed 10 Vdc between loops. Excess voltage may damage the Analog Input Module (AIM). Input Wiring Recommendations Use multicolored stranded shielded cable for analog inputs. WatlowAnafaze recommends that you use #20 AWG wire. (If the sensor manufacturer requires it, you can also use #22 or #24 AWG wiring.) Most inputs use a shielded twisted pair; some require a 3-wire input.
Installation To MLS-AIM Circuitry Analog Input Terminal A+ IN + Internal +2.5 Vdc Reference RA RD RB RC A- IN C .47 uF A COM C .47 uF This table shows scaling resistor values. Input Range RA RB All T/C, 0-60 mVdc RC RD Jumper RTD1 -100.0 to 300.0ºC RTD2, -120 to 840ºC RTD3, -70 to 300ºC 5.49K 11.0K 11.0K 0-10 mAdc 0-20 mAdc (4-20 mA) -450 to 2500 0-100 mVdc 0-500 mVdc 0-1 Vdc 0-5 Vdc 0-10 Vdc 0-12 Vdc 5.49K 11.0K 11.0K 80 100 100 Jumper Jumper 6.0 3.0 499 5.49K 6.91K 39.2K 49.9K 84.
Installation 2. Select the # of digits and decimal point location for the full scale PV display. The smallest possible range is -0.9999 to +3.0000; the largest possible range is -9999 to 30000. 3. Enter the zero and full scale values (process variables) you want displayed when the input signal is at zero and full scale. T/C Inputs WARNING Use ungrounded thermocouples (thermocouples which have the T/C junction isolated from the metal protection sheath).
Installation Connecting Thermocouples Connect the positive T/C lead to the A+ terminal. Connect the negative T/C lead to the A- terminal of TB1. The figure below shows a typical thermocouple connection. • Use 20 gauge T/C extension wire for all T/C inputs. • If you use shielded wire, tie the shield to panel ground. • Install a jumper or zero ohm resistor in location RC on the AIM-TB if it had been removed. This figure shows a typical thermocouple connection.
Installation Rear Terminal Block Connections Black IN + Black IN – 100 Ohm RTD Red Analog Common Current Inputs To install current (milliamp) inputs, place resistors in the input section which convert the milliamp input into a voltage. (You can get different current input ranges if you select different resistor values.) The input connections for these inputs are the same as the input connections for voltage inputs. Voltage Inputs Connect the + side of the voltage input to the A+ terminal.
Installation Communications The MLS is factory-configured for either RS-232 or RS-485 communications. When you order your unit, specify the type of communications you need. • If you use one MLS and you connect it to a computer less than 50 feet away, you can use RS-232 communications. • If you use more than one computer, or if the computer and controller are more than 50 feet apart, use RS-485 communications. PC-compatible computers typically use RS-232 communications.
Installation 1. Plug the phone connector into the slot labeled "RS-232/RS-485" on the rear of the MLS-PM. 2. Plug the D-sub connector into the communications connector. This table shows RS-232 connections for 25-pin and 9-pin connectors. Computer Connector DB 25 DB 9 MLS RS-232 Pin Number RX Pin 3 RX Pin 2 TX Pin 5 Yellow TX Pin 2 TX Pin 3 RX Pin 1 Blue GND Pin 7 GND Pin 5 GND Pin 4 Green NOTE The pin numbers and colors are not industry standard.
Installation Black Box LD 485A TXA TXB RXA RXB Ground MLS T3A/B [n] RJ12 MLS T3A/B [1] RJ12 Red Blue/White Black Yellow Silver RX+ #3 RX- #1 TX+ #2 TX- #5 #6 Red Blue/White Black Yellow Silver RX+ #3 200Ω RX- #1 TX+ #2 TX- #5 #6 NOTE Connect the shields to earth ground only at the computer or other 485 interface. Do not connect the shield at the MLS. Connect a 200 ohm terminating resistor between RX- and RX+ at the last MLS (Ju3).
Installation Recommended Wire Gauges This table shows maximum distances and wire gauges for communications wiring: Distance Wire Gauge Recommended Cable 4000 ft. 24 AWG Belden #9729 Belden #9842 6000 ft. 22 AWG Belden #9184 You may wish to use a shield, depending on your noise environment and grounding problems. These cables are shielded.
Installation 46 MLS User’s Guide
Using the MLS Using the MLS This chapter explains how to use the front panel to operate the controller. (If you are using ANASOFT, see the operation instructions in the ANASOFT User's Guide.) The next figure shows a map of the operator menus and displays accessible from the MLS Controller's front panel. You don't need to enter a passkey sequence to reach these menus.
Using the MLS Front Panel The MLS front panel provides a convenient interface with the controller. You can use the front panel keys to program and operate the MLS, or you can use ANASOFT, a program designed specifically for ANAFAZE controllers. (See the ANASOFT User's Guide for more information about ANASOFT, or contact ANAFAZE.) This figure shows the MLS' front panel.
Using the MLS Front Panel Keys Yes (Up) Press Yes to do these things: • Select a menu. • Answer Yes to Yes/No prompts. • Increase a number or choice you're editing. • Stop scanning mode. No (Down) Press No to do these things: • Skip a menu when the prompt is blinking. • Answer No to Yes/No prompts. • Decrease a number or choice when editing. • Stop scanning mode. • Perform a manual controller (No Key) reset (see next page).
Using the MLS • Switch between Bar Graph and Single Loop display. Enter Press the "Enter" key to: • Store data or a menu choice after editing. • Go on to the next menu. • Start scanning mode (if pressed twice). Chng SP • Press this key to change the loop setpoint. Man/Auto Press the Man/Auto key to: • Toggle a loop between manual and automatic control. • Adjust the output power level of manual loops. • Automatically tune the loop. Ramp/Soak Ramp/Soak isn't available for the standard MLS.
Using the MLS Displays This section describes the MLS' displays. Viewing Several Loops: Bar Graph Display When you connect power to the MLS, it displays general symbolic information for loops 1-8. This display is called Bar Graph mode. The next figure shows a picture of the Bar Graph display. LOOP PROCESS 01 AAAA UNITS 08 MAMA ALARM SETPOINT STATUS OUT% This table explains the symbols on the top line of the Bar Graph display.
Using the MLS Bar Graph DisplaySy mbol Single Loop DisplaySy mbol Description M MAN One or both outputs enabled. Loop is in manual control. A AUTO Only one output (Heat or Cool) is enabled. Loop is in automatic control. T TUNE Indication that the loop is in Autotune mode. H T HEAT Both heat and cool outputs are enabled. Loop is in Automatic control and heating. C L COOL Both heat and cool outputs are enabled. Loop is in Automatic control and cooling.
Using the MLS If only one output is enabled (heat or cool, but not both), Single Loop display looks like this: Engineering Units Process Variable Loop Number Output Percentage LOOP PROCESS UNITS or Name Cool 02 160 ºF 0 180 AUTO 100 Output Percentage Setpoint ALARM SETPOINT STATUS OUT% Heat Control Status Navigating in Single Loop Display From the single loop display, • Press the Back key once to get back to Bar Graph display. • Press Enter twice to get to the Single Loop Scanning display.
Using the MLS This table shows the symbols used in each form of the alarm display. Bar Graph Symbol Single Loop Symbol Description > HP High Process Alarm > HD High Deviation Alarm < LP Low Process Alarm < LD Low Deviation Alarm B T/C Break Open Input Error S O RTD Short RTD Open RTD Short Alarm RTD Open Alarm Aim Comm Failure Aim Fail MLS-AIM Communications Failure Acknowledging an Alarm Press Alarm Ack to acknowledge the alarm.
Using the MLS Displaying, Loading, and Saving Jobs Job display appears only if: • You have turned on the Remote Job Select function. (This function is explained in Chapter 4: Setup.) • You have selected a job from the job load menu.
Using the MLS Operator Menus You can perform these tasks from Single Loop Display. Changing the Setpoint Press Chng SP from the loop you want to change. this display appears: LOOP PROCESS UNITS 01 SETPOINT ? 25 ALARM SETPOINT STATUS OUT% • Press Yes to change the setpoint. • Press Yes or No to change the setpoint value. • Press Enter to save your changes and return to Single Loop Display. • Press No or Back to return to Single Loop Display without saving the new setpoint.
Using the MLS • Press Enter, then Back to store the new mode and return to Single Loop Display without setting an output level. NOTE If the loop outputs are disabled, you cannot toggle between Manual and Automatic output control. If you try it, the screen shows an error message telling you that the outputs are disabled, as shown below. Use the menus in the Setup Loop Outputs main menu to enable the outputs. (See Chapter 4: Setup for more information about the Setup menus.
Using the MLS Automatically Tuning a Loop When you use the Autotune function, the controller automatically sets the loop to Manual control, 100% output. (If you selected a continuous output limit, the controller sets the loop to the output limit.) The autotune function calculates the appropriate PID constants for the loop and puts the loop in automatic control with the calculated PID values. The Autotune function will abort if: • The process variable goes over 75% of the setpoint.
Setup The Setup menus let you change the MLS' detailed configuration information. If you have not set up a Modular Loop System before, or if you don't know what values to enter, please read first the next chapter, Tuning and Control which contains PID tuning constants and useful starting values. How to enter the Setup menus? 1. In Single Loop Display, select the loop you wish to edit. 2. While still in Single Loop Display, enter the pass sequence below: Press Enter, Alarm Ack, Change Setpoint. 3.
Setup Setup Loop xx Input? Setup Global Parameters? save setup to job? Load setup from job? Input type? Pulse sample time? Loop name? Job control dig inputs? Job digital input true? Output override dig input? Input units? Input reading offset (T/C & RTD)? Override dig in active? Startup alarm delay? Disp format (Linear & Pulse)? Input scaling Hi pv? (Linear & Pulse) Keyboard lock status? Input scaling Hi rdg? (Linear & Pulse) Power up output status? Input scaling Lo pv? (Linear & Pulse) Input sca
Setup Setup Global Parameters Menu The setup global parameters menu looks like this LOOP PROCESS UNITS SETUP GLOBAL PARAMETERS? ALARM SETPOINT STATUS OUT% Below is the setup global parameters menu tree. Notice the default values inside the boxes.
Setup Save to Job Use this menu to save the job information for every loop to one of eight jobs in the MLS’ battery-backed RAM. LOOP PROCESS UNITS SAVE SETUP TO JOB? 1 ALARM SETPOINT STATUS OUT% Selectable Range: 1-8.
Setup Job Select Inputs Use the Remote Job Control feature to run up to 8 jobs remotely. The Job Select Inputs menu is the third menu under Setup Global Parameters. It lets you set the number of job select inputs. The controller uses these inputs as a binary code that specifies the job number to run. The number of inputs you choose in this menu controls the number of jobs you can select remotely.
Setup Job Digital Input Polarity Use this menu to set the polarity of the digital outputs used for job selection. You can set the Active state to closed (Low) or open (High). LOOP PROCESS UNITS JOB DIGITAL INPUT TRUE? LOW ALARM SETPOINT STATUS OUT% Selectable values: Low or High. Output Override Digital Input This menu lets you set a digital input that sets all loops in manual output at output levels you select in the Outputs menu.
Setup Startup Alarm Delay Use this menu to set a startup delay for process and deviation alarms for all loops. The controller does not report these alarm conditions for the specified number of minutes after the controller powers up. (The controller will always report failed sensor alarms, no matter what startup delay you set.) LOOP PROCESS UNITS STARTUP ALARM DELAY? 0 mins ALARM SETPOINT STATUS OUT% Selectable Range: 0-60 minutes.
Setup Controller Address Use this menu to set the MLS controller address. The controller address is used for multiple controller communications on a single RS-485 cable, so each MLS must have a different address. Begin with address 1 for the first controller and assign each subsequent controller the next higher address. LOOP PROCESS UNITS CONTROLLER ADDRESS? 1 ALARM SETPOINT STATUS OUT% Selectable Range: a number between 1 and 32.
Setup Communications Baud Rate Use this menu to set the Communications Baud Rate to 2400 or 9600 baud. LOOP PROCESS UNITS COMMUNICATIONS BAUD RATE? 9600 ALARM SETPOINT STATUS OUT% Selectable values: 9600 or 2400. NOTE If you use ANASOFT, be sure to set ANAINSTL to the same baud rate that you set in this menu. Allen Bradley Protocol Use this menu to set the protocol type to either Allen Bradley or ANAFAZE.
Setup Digital Output Polarity Use this menu to set the polarity of the digital outputs used for alarms. The output can be active High or active Low. LOOP PROCESS UNITS DIGOUT OUTPUTS ACTIVE? LOW ALARM SETPOINT STATUS OUT% Selectable values: High or Low. AIM Communications Failure Output Use this menu to select the digital output that activates if communications fail between the MLS-AIM and the MLS-PM.
Setup Setup Loop Input The Setup Loop Input main menu lets you access menus which change loop input parameters: • Input type • Input scaling and calibration • Input filtering The next section explains how to configure inputs via the front panel. LOOP PROCESS UNITS SETUP LOOP 02 INPUT? ALARM SETPOINT STATUS OUT% Below is the menu tree for the Setup Loop Inputs menu. Notice the default values inside the boxes.
Setup Input Type Use this menu to configure the input sensor for each loop as one of these input types: • Thermocouple types (J, K, T, S, R and B). • RTD. Three ranges: RTD1 (Platinum Class A), RTD2 (Platinum Class B), and RTD3 (Nickel). • Linear and Pulse inputs. • Skip (an input type available for unused channels.) The scanning display doesn't show loops you've set to Skip. LOOP PROCESS UNITS 06 INPUT TYPE? J T/C ALARM SETPOINT STATUS OUT% The next table shows the MLS' input types and ranges.
Setup Pulse Sample Time You can connect a digital pulse signal of up to 2 KHz to the controller’s pulse input. Use this menu to specify the pulse sample period. Every sample period, the number of pulses the controller receives is divided by the sample time. The controller scales this number and uses it as the pulse loop’s PV. LOOP PROCESS UNITS 06 INPUT PULSE SAMPLE TIME? 1s ALARM SETPOINT STATUS OUT% Selectable range: 1-20 seconds. Loop Name Use this menu to name your loop.
Setup Input Reading Offset Use this menu to make up for the input signal's inaccuracy. For example, at temperatures below 400 ºF, a type J thermocouple may be inaccurate ("offset") by several degrees F. Use an independent thermocouple or your own calibration equipment to find the offset for your equipment. To correct for offset errors, change the factory default setting to a positive or negative value for the loop you are editing. (A positive value increases the reading and a negative value decreases it.
Setup The graph below shows pressure as an example. Before you enter the values that determine the two points for the conversion line, you must choose an appropriate display format. The MLS has six characters available for process variable display; select the setting with the desired number of decimal places before and after the decimal point. Use a display format that matches the range and resolution of the process variable.
Setup Display Format Use this menu to select a display format for a linear input. Choose a format appropriate for your input range and accuracy. LOOP PROCESS UNITS 05 DISP FORMAT -9999 TO 30000 ALARM SETPOINT STATUS OUT% Selectable values: The MLS has several available display formats, as shown below. this table shows also the high and low PV values. . Display Formats High PV Default Low PV Default -9999 to +30000 10000 0 -999 to +3000 1000 0 -99 to +300 100 0 -9 to +30 10 0 -.
Setup High Reading Use this menu to enter the input level that corresponds to the high process value you entered in the previous menu. For linear inputs, the high reading is a percentage of the full scale input range. For pulse inputs, the high reading is expressed in Hz. The 100% full scale input value is 60 mV for the linear input type. LOOP PROCESS UNITS 09 INPUT SCALING HI RDG = 100.0% FS ALARM SETPOINT STATUS OUT% Selectable range: Any value between -99.9 and 110.0.
Setup Input Filter Access this menu from the Setup Loop Inputs main menu. The MLS has two different types of input filter: • A noise rejection filter that rejects high frequency input signal noise. This filter keeps a "trend log" of input readings. If a reading is outside the filter's "acceptance band", and later readings are within the acceptance band, the MLS ignores the anomalous reading. (The acceptance band for thermocouples is 5 degrees above and 5 degrees below the input reading.
Setup Setup Loop Control Parameters Use these menus to change control parameters for heat and cool outputs of the selected loop, including: • Proportional Band (PB), Integral (TI or Reset), and Derivative (TD or Rate) settings. • Output Filter. • Spread between heat and cool outputs.
Setup Heat/Cool Control PB Use this menu to set the Proportional Band. LOOP PROCESS UNITS 01 HEAT CONTROL PB? 50 ºF ALARM SETPOINT STATUS OUT% NOTE The MLS internally represents the proportional band (PB) as a gain value. When you edit the PB, you'll see the values change in predefined steps--small steps for narrow PB values and large steps for wide PB values.
Setup Heat/Cool Output Filter Use this menu to dampen the heat or cool output's response. The output responds to a step change by going to approximately 2/3 of its final value within the number of scans you set here. LOOP PROCESS UNITS 07 HEAT CONTROL FILTER ? 2 ALARM SETPOINT STATUS OUT% Selectable range: 0-255. Setting the output filter to 0 turns it off. Heat/Cool Spread Use this menu to set the spread between the heat and cool output and the spread of the On/Off control action.
Setup Setup Loop Outputs Press Yes at this prompt to access menus to change loop output parameters for the current loop, including: • Enable or disable outputs • Output type • Cycle time (for TP outputs) • SDAC parameters (for SDAC outputs) • Control action • Output level limit and limit time • Output override • Nonlinear output curve Both heat and cool outputs have the same menus, so only one of each menu is explained in this section. (The next page shows a menu tree.
Setup Setup Loop Outputs? Output disabled Heat/Cool control out? Output Enabled For TP outputs For SDAC outputs Heat/cool output cycle time? 10 S For ON/OFF DZC Heat/Cool output type? SDAC mode? Voltage SDAC Lo value? 0.00 SDAC Hi value? 10.
Setup Enable/Disable Heat and Cool Outputs Use this menu to enable or disable the heat or cool output for the current loop. If you want the loop to have PID control, you must enable one output. You can also disable a heat or cool control output and use the output pin for something else, like an alarm. LOOP PROCESS UNITS 05 HEAT CONTROL OUT? ENABLED ALARM SETPOINT STATUS OUT% Selectable values: Enabled or Disabled. The default setting enables the heat outputs and disables the Cool outputs.
Setup Heat/Cool Cycle Time Use this menu to set the Cycle Time for Time Proportioning outputs. LOOP PROCESS UNITS 03 HEAT OUTPUT CYCLE TIME ? 10S ALARM SETPOINT STATUS OUT% Selectable range: 1-255 seconds. NOTE The Cycle Time menu will only be present if the output type for the current loop is Time Proportioning. SDAC Menus If you attach the optional SDAC to an output, you must configure that output for the SDAC using the following series of menus.
Setup SDAC High Value Use this menu to set a high value for the SDAC output. Set the high and low value to match the range of the output device. For instance, if the output device has a 4-20 mA range, set the SDAC high value to 20.00 mA and the SDAC low value to 4.00 mA. The controller converts 0% output to a 4.00 mA signal and 100% output to a 20.00 mA signal. LOOP PROCESS UNITS 03 SDAC HI VALUE ? 10.
Setup Heat/Cool Output Limit Use this menu to limit the maximum PID control output for a loop's heat and cool outputs. This limit may be continuous, or it may be in effect for a specified number of seconds (see Output Limit Time on the next page). If you choose a timed limit, the output limit restarts when the controller powers up and when the output goes from Manual to Automatic control (via the front panel, when the controller changes jobs, or from ANASOFT.
Setup Heat/Cool Nonlinear Output Curve Use this menu to select one of two nonlinear output curves for nonlinear processes. LOOP PROCESS UNITS 03 OUTPUTS HEAT NLO ? OFF ALARM SETPOINT STATUS OUT% Selectable values: Curve 1, Curve 2, or Off (linear/no curve). The linear curves are shown in the figure below.
Setup Setup Loop Alarms Press Yes at the Setup Loop Alarms prompt to access menus which change alarm function parameters for the current loop. The main alarms menu looks like this: LOOP PROCESS UNITS SETUP LOOP 04 ALARMS ? ALARM SETPOINT STATUS OUT% Below is the alarms menu tree. Notice the default values inside the boxes.
Setup Alarm Types The MLS has three different kinds of alarms: failed sensor alarms, global alarms, and process alarms. Failed Sensor Alarms Failed sensor alarms alert you to T/C breaks and these RTD open or short failures: • Open + or - input. • Short between + and - input. When the loop is in Automatic or Tune mode and a failed sensor alarm occurs, the MLS sets the loop to Manual control at the failed sensor percentage you set in the Setup Loop Outputs menus.
Setup When the controller powers up or the setpoint changes, deviation alarms do not activate until the process goes inside the deviation alarm band-preventing deviation alarms during a cold start. (High and low process alarms are always enabled.
Setup Alarm Delay You can set the MLS to delay normal alarm detection and alarm reporting. There are two kinds of alarm delay: • The startup alarm delay delays process alarms (but not failed sensor alarms) for all loops for a time period you set in the Setup Global Parameters main menu. • The loop alarm delay delays failed sensor alarms and process alarms for one loop until the alarm condition is continuously present for longer than the loop alarm delay time you set.
Setup High Process Alarm Setpoint Use this menu to select the setpoint (temperature or other value within the scaled sensor range) at which the high process alarm activates. The high process alarm activates when the process variable (PV) goes above the high process setpoint. It deactivates when the PV goes below the high process setpoint minus the deadband value, if you have set a deadband value.
Setup NOTE All digital outputs are "OR'ed" together (combined). Therefore you can assign more than one alarm to the same output number, and that output will be On if any of those alarms is On. Deviation Band Value Use this menu to set the deviation bandwidth, a positive and negative alarm or control point relative to the setpoint. If the setpoint changes, the alarm or control points also change.
Setup High Deviation Alarm Output Number Use this menu to assign a digital output which activates when the loop is in high deviation alarm. The digital output only activates if you have set the high deviation alarm type to Alarm or Control. LOOP PROCESS UNITS 01 HI DEV ALARM DIG OUT ? NONE ALARM SETPOINT STATUS OUT% NOTE All digital outputs are "OR'ed" together (combined). Therefore you can assign more than one alarm to the same output number, and that output will be On if any of those alarms is On.
Setup NOTE All digital outputs are "OR'ed" together (combined). Therefore you can assign more than one alarm to the same output number, and that output will be On if any of those alarms is On. Low Process Alarm Setpoint Use this menu to set a low process alarm setpoint. (The low process alarm activates when the process variable goes below the low process alarm setpoint. It deactivates when the process variable goes above the low process alarm setpoint plus the deadband.
Setup NOTE All digital outputs are "OR'ed" together (combined). Therefore you can assign more than one alarm to the same output number, and that output will be On if any of those alarms is On. Alarm Deadband Use this menu to set an alarm deadband. This deadband value applies to the high process, low process, high deviation, and low deviation alarms for the loop you are editing. Use the Alarm Deadband to avoid repeated alarms as the PV cycles slightly around an alarm value.
Setup Manual I/O Test Press Yes at this prompt to see menus which can help you test the digital inputs, digital outputs and the MLS' keypad. LOOP PROCESS UNITS MANUAL I/O TEST ? ALARM SETPOINT STATUS OUT% The next figure shows the I/O Test menu tree. Notice the default values inside the boxes.
Setup Digital Input Testing Use this menu to view the logic state of the 8 digital inputs as H (High-the input is at 5 volts or is not connected) or L (Low--the input is at zero volts). The menu displays inputs 1 to 8 from left to right. Since inputs are pulled High when they are not connected, test an input by shorting it to controller common and making sure this menu shows the correct state for that input.
Setup Toggle Digital Output Use this menu to manually toggle a digital output On or Off to test it. (You select the output to test in the previous menu.) On may be Low or High depending on the digital output polarity you set in the Output Polarity menu. (All outputs are set to Off when you exit Manual I/O Test menu.) LOOP PROCESS UNITS DIGITAL OUTPUT NUMBER 17? OFF ALARM SETPOINT STATUS OUT% Selectable values: On or Off.
Tuning and Control Tuning and Control Introduction This chapter explains PID control and supplies some starting PID values and tuning instructions, so that you can use control parameters appropriate for your system. If you would like more information on PID control, consult the ANAFAZE Practical Guide to PID. The control mode dictates how the controller responds to an input signal. The control mode is different from the type of control output signal (like analog or pulsed DC voltage).
Tuning and Control The next diagram shows a process under On/Off control. Proportional Control A process using On/Off control frequently cycles around the setpoint. When process variable cycling is unacceptable or the process or setpoint are variable, use proportional control. Proportional control, or Gain, eliminates cycling by increasing or decreasing the output proportional to the process variable's distance from the setpoint.
Tuning and Control Proportional and Integral Control For Proportional and Integral control, use the Integral term, or Reset, with Proportional control. The Integral term corrects for offset by repeating the Proportional band's error correction until there is no error. For example, if a process tends to settle about 5 ºF below the setpoint, use Integral control to bring it to the desired setting. The next diagram shows a process under proportional and integral control.
Tuning and Control Digital Output Control Forms The next section explains different modes for control outputs. On/Off On/Off output is very simple: it turns the output on or off according to the control signal of the On/Off control. Time Proportioning (TP) Time Proportioning attempts to digitally simulate an analog output percentage by turning the output On or Off for each time step, so that the cumulative average of the output is the desired setting. You must enter a cycle time for TP outputs.
Tuning and Control ANAFAZE also offers the DAC, another optional analog output module for the MLS. It converts two DZC outputs to two 4-20 mA current outputs. Output Digital Filter The output filter digitally filters the PID control output signal. It has a range of 0-255 levels, which gives a time constant of 0-127.5 seconds.
Tuning and Control Setting Up and Tuning PID Loops To start your process after installation, tune the control loops and set them to automatic control. If the loop is already in automatic control mode and controlling the process, set the loop to manual control. Then you can tune it without upsetting the process. However, if you don’t mind minor process fluctuations, you can tune the loop in automatic control mode. NOTE Remember that tuning is a slow process.
Tuning and Control Integral Term (TI) Settings This table shows Integral vs. Reset repeats per minute. TI (secs./repeat) Reset (repeats/min) TI (secs./repeat0 Reset (repeats/min) 30 2.0 210 0.28 45 1.3 240 .25 60 1.0 270 .22 90 .66 300 .20 120 .50 400 .15 150 .40 500 .12 180 .33 600 .10 Setting the TI: A General Rule Use 60, 120, 180, or 240 as a starting value for the TI. Derivative Term (TD) Settings This table shows Derivative term (TD) vs. Rate Minutes (RM); Rate=TD/60.
Tuning and Control General PID Constants This section gives general PID constants. Proportional Band Only (P) Set the PB to 7% of the setpoint Example: Setpoint = 450, set the Proportional Band to 31. Proportional with Integral (PI) Set the PB to 10% of setpoint. Example: Setpoint = 450, set PB to 45. Set TI to 60. Set TD to Off. Set the Output Filter to 2. PI with Derivative (PID) Set the PB to 10% of the SP. Set the TI to 60. Set the TD to 15% of the TI. Example: TI = 60, so TD = 9).
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Troubleshooting Troubleshooting The next few sections describe general troubleshooting for the MLS. Later sections describe specific procedures, like checking an input, changing the EPROM, and testing the controller. First, Check your Installation The controller is only part of your control system. Often, what appears to be a problem with the MLS is really a problem with other equipment, so check these things first: • Controller is installed correctly. (See Chapter 2: Installation for help.
Troubleshooting WARNING A manual controller reset clears the MLS memory and resets its parameters to their default values. If you reset a stand-alone system, you cannot recover your original parameters. If you have a computer supervised system, ANASOFT stores a copy of your parameters. Do not attempt to repair the MLS yourself. There are no user-repairable components in the MLS.
Troubleshooting Keys Don't Respond If the MLS seems to function perfectly, but the Man/Auto, Chng SP, Alarm Ack, and Ramp/Soak keys do not respond when you press them, then you are probably locked out of the system. Ask your supervisor to unlock the keyboard according to the instructions in the Setup Global Parameters section.
Troubleshooting • To check thermocouple inputs, unplug the AIM module and measure between the A+ and A- terminals of the AIM-TB. Thermocouple inputs should not read above 200 ohms. • To check RTD inputs, unplug the AIM module and measure between the A+ and A- terminals. Then measure between the A+ and A COM terminals of the AIM-TB. RTD inputs should read between 20 and 250 ohms. Both readings should be the same. Make sure other inputs operate within the AIM's full scale voltage (60 mVdc).
Troubleshooting Checking Computer Supervised Systems These four elements must work properly in a computer-supervised system: • The MLS. • The computer and its RS-232 or RS-485 serial interface. • The RS-232 or RS-485 communication lines. • The computer software. For MLS troubleshooting, disconnect the communications line from the computer and follow the troubleshooting steps in the first section of this chapter.
Troubleshooting If you use the Black Box RS-485 interface, make sure you have set it up correctly. (See the Communications section in Chapter 2 for RS-485 setup instructions.) The LEDs on the unit should blink, but should not stay lit. For either type of interface, you can connect an oscilloscope to the transmit or receive line to see whether data is being sent or received. If the serial interface does not function, contact your computer service representative.
Troubleshooting Software Problems This section gives some solutions for software problems. User-Written Software If you don't want to use ANASOFT as your software interface to the MLS, you are responsible for the correct operation of the software you buy or write. You can request the ANAFAZE Communications Specification if you want to write your own software.
Troubleshooting Changing the EPROM Changing the EPROM involves minor mechanical disassembly and reassembly of the controller, but you don't need any soldering or electrical expertise. You'll need a Phillips head screwdriver and a small flathead screwdriver. NOTE If you change the EPROM, you must perform a manual controller reset for the EPROM change to take effect.
Troubleshooting 5. Locate the EPROM on the circuit board. The EPROM is a 28-pin socketed chip which may have an ANAFAZE label on top of it. If there is no label, a small window will be visible in the middle of the top of the chip. Do not confuse the EPROM with the RAM; the RAM also has 28 pins, but it is in a high-profile socket, and it does not have a label or a window. (The component designation U2 is printed on the processor board next to the EPROM socket.
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Linear Scaling Examples Linear Scaling Examples Example 1: Configuring a Pressure Sensor You’re using a pressure sensor that generates a 4-20 milliamp signal. The sensor generates 4 milliamps at 0.0 PSI and 20 mA at 50.0 PSI. Setup You connect the sensor to a loop input set up with a resistor scaling network to produce 60 millivolts at 20 mA. (See the Inputs section of Chapter 2: Installation for more information on scaling networks.
Linear Scaling Example 2: Configuring a Flow Sensor You connect a flow sensor to the MLS to measure the flow in a pipe. The sensor generates a 0-5V signal. The sensor's output depends on its installation. Measurements of the flow in the pipe indicate that the sensor generates 0.5 volts at three gallons per minute (GPM) and 4.75 volts at 65 GPM. The calibration instruments are precise to +1 gallon per minute.
Glossary A AC See Alternating Current. AC Line Frequency The frequency of the AC power line measured in Hertz (Hz), usually 50 or 60 Hz. Accuracy Closeness between the value indicated by a measuring instrument and a physical constant or known standards. Action The response of an output when the process variable is changed. See also Direct action, Reverse action. Address A numerical identifier for a controller when used in computer communications.
Glossary MLS User’s Guide Block Check Character (BCC) A serial communications error checking method. An acceptable method for most applications, BCC is the default method. See CRC. Bumpless Transfer A smooth transition from Auto (closed loop) to Manual (open loop) operation. The control output does not change during the transfer. C Calibration The comparison of a measuring device (an unknown) against an equal or better standard. Celsius (Centigrade) Formerly known as Centigrade.
MLS User’s Guide Glossary deadband. It is usually above the heating proportional band and below the cooling proportional band. Default Parameters The programmed instructions that are permanently stored in the microprocessor software. Derivative Control (D) The last term in the PID algorithm. Action that anticipated the rate of change of the process, and compensates to minimize overshoot and undershoot.
Glossary MLS User’s Guide F is cleared directly from a controller or through a user interface. Fahrenheit The temperature scale that sets the freezing point of water at 32ºF and its boiling point at 212ºF at standard atmospheric pressure. The formula for conversion to Celsius is: ºC=5/9 (ºF-32ºF). Global Digital Outputs A pre-selected digital output for each specific alarm that alerts the operator to shut down critical processes when an alarm condition occurs.
MLS User’s Guide Glossary heating and infrared (noncontact) temperature sensing. changes reflectance or transmittance when an electrical field is applied to it. Input Process variable information that is supplied to the instrument. Load The electrical demand of a process, expressed in power (watts), current (amps), or resistance (ohms). The item or substance that is to be heated or cooled.
Glossary MLS User’s Guide See Electromagnetic Interference. Noise Suppression The use of components to reduce electrical interference that is caused by making or breaking electrical contact, or by inductors. Non Linear Through ANAFAZE software, the Non Linear field sets the system to linear control, or to one of two non linear control options. Input 0 for Linear, 1 or 2 for non linear. O Offset The difference in temperature between the setpoint and the actual process temperature.
MLS User’s Guide Glossary cal encoders. R Ramp A programmed increase in the temperature of a setpoint system. Range The area between two limits in which a quantity or value is measured. It is usually described in terms of lower and upper limits. Recipe See Job. Reflection Compensation Mode A control feature that automatically corrects the reading from a sensor. Relay A switching device.
Glossary MLS User’s Guide conductors that is designed to prevent electrostatic or electromagnetic interference from external sources. Signal Any electrical transmittance that conveys information. Solid State Relay (SSR) See Relay, Solid State. Span The difference between the lower and upper limits of a range expressed in the same units as the range. Spread In heat/cool applications, the +/- difference between heat and cool. Also known as process deadband. See deadband.
MLS User’s Guide Glossary V Volt (V) The unit of measure for electrical potential, voltage or electromotive force (EMF). See Voltage. Voltage (V) The difference in electrical potential between two points in a circuit. It’s the push or pressure behind current flow through a circuit. One volt (V) is the difference in potential required to move one coulomb of charge between two points in a circuit, consuming one joule of energy.
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