026-1307 Rev 3 06-APR-2010 Modular Refrigerant Leak Detection Sensor (MRLDS) Installation and Operation Manual
240 Town Point Drive NW Suite 100 Kennesaw, GA 30144, USA Phone 770-425-2724 Fax 770-425-9319 ALL RIGHTS RESERVED The information contained in this manual has been carefully checked and is believed to be accurate. However, Computer Process Controls, Inc. assumes no responsibility for any inaccuracies that may be contained herein. In no event will Computer Process Controls, Inc.
Table Of Contents 1 OVERVIEW ................................................................................................................................................................... 1 1.1 SPECIFICATIONS ............................................................................................................................................................. 1 1.2 MRLDS MODELS .........................................................................................................................
1 Overview Retail Solutions specs a modular refrigerant leak detection sensor (MRLDS) that continuously monitors for low levels of refrigerants most commonly used in commercial refrigeration systems. The MRLDS communicates with the E2 controller via a Gateway board connected to the RS485 I/O Network, or via the analog input on a MultiFlex board. 1.1 Specifications Power Requirements 24 VAC, ±20%, 50/60 Hz, Class 2 Wiring 14 AWG max, Class 2 copper wiring Power Consumption Less than 2.
If a transformer is shared between MRLDS units, the “ACN” of each MRLDS must be wired to the same phase of the transformer. 120VAC Tr MRLDS I MRLDS II er 24VAC rm o sf an ACN Figure 1-2 - Powering Multiple MRLDS Units 2 Choosing a Mounting Location Figure 2-1 - Sensor Base And Cover 2.1 Mounting The Sensor The refrigeration monitor comprises two basic parts: the base and the cover. The cover incorporates the circuit board with the sensing elements.
3 MRLDS Analog Version (809-100x) 3.1 Network Layout E2 s r vice he Ot t De To Ne O I/ Figure 2-2 - Attaching and Removing Cover I/O Net 2.2 MRLDS Dimensions MultiFlex Board MRLDS Units Figure 3-1 - Analog MRLDS Network Layout Example 3.2 MRLDS Wiring For analog MRLDS units, connect to a MultiFlex board via the analog input (use Belden 8761 cable).
3.3 Refrigerant Jumper Settings 5. Select the board/point input. 6. Press F1 Setup. 7. Select Analog Sensor. The jumper settings for refrigerant types are located on the label inside the MRLDS sensor cover (shown in Figure 1-1). Set the jumpers according to how they are indicated on the label. 8. On the Analog Input screen, select MRLDS Refr. as the Sensor Type. The parameters are then automatically configured for you. 9. Press the (Back) button to save changes.
4.2 MRLDS Setup 4.2.1 MRLDS Wiring RS485 (-) RS 485 (+) MODBUS NETWORK Figure 3-4 - Analog Input Screen Settings Example for E2 3.4.3 BELDEN 8761 RMCC Controllers To Gateway Board EARTH GND ACN 24VAC MODBUS MRLDS - INSIDE LOWER PORTION OF BASE 14 AWG less than 6 inches Shield drain/ground wire For RMCC-type controllers, set the Gain parameter to 250 and Offset to -1000. 4 MRLDS Modbus Version (809-101x) 4.
4.2.3 Address Settings Modbus Address Jumper Settings the J2 or J1 sockets respective per the inside label.
Factory Mode 4 (Lsb) J6 Trouble Mode 8 (Lsb) J1 Termination jumper J6 J5 J4 J3 J2 J1 Figure 4-5 - MRLDS Termination (Inside Lower Left of Cover) 4.2.6 Modbus Output Fault and Module State PDU Address 0x0000 Logical Address 1 0x0001 2 0 to 40 Gas Concentration 0x0002 3 -20 to 1050 (PPM) Gas Numbers R-22 = 6 R-404A = 27 R-134a = 15 Table 4-3 - RS485 Output Specifications See Table 4-3 below for Modbus registers in the MRLDS Unit.
way board (P/N 810-3040). The Gateway board can interface with a site controller as a 16AI or as an IRLDS. If the site controller is an Einstein or E2, it is recommended to interface them as an IRLDS. Multiple Gateways can be used, each with up to 12 connected MRLDS units. 4.3.3 The Gateway Board Figure 4-8 shows how to connect the 56VA and 80VA transformers to the Gateway power connector.
controller’s user manual. GATEWAY BOARD RS485 I/O NET TERM JUMPERS -485 0v +485 RS485 I/O NET (TO CPC CONTROLLER) TERMINATION (ALWAYS TERMINATE) Figure 4-9 - Connecting the Gateway to the E2 RS485 Network To connect the Gateway to an MRLDS, feed the wires through the rectangular opening in the sensor base as indicated in Figure 1-1. Locate the RS485 connector and secure the wire leads to the connector orienting them as shown in Figure 4-10.
4.3.9 Setting the Baud Rate Dip Switches Dip switches 6 and 7 control the baud rate at which the Gateway communicates with the site controller on the RS485 Network. These switches must be set to the same baud rate setting as the controller you are using (Einstein, RMCC, or E2), and defaults to 9600 baud. Dip switch 8 controls the baud rate at which the Gateway communicates with the MRLDS. For 9600 baud, set dip switch 8 to the OFF position.
4.3.11 Gateway Troubleshooting 100: GAS: ST: ALM: FAIL CNT: 1 R134A NORMAL NONE I/O NET Figure 4-17 - Status Screen NOTE: If the HHT displays any type of alarm, contact the Retail Solutions Service Department (770-425-2724) to verify if the MRLDS unit should be replaced. 4.3.10.4 Setup/Online Screen 2 - The Setup/Online screen displays the addressing of the devices and whether they are enabled. Press the right/ left arrows to select the first address in the list.
4.4.4 ways. Navigate to the controller’s Input Status screen and highlight the board and point that you wish to map. Press F1 to go to the Input Setup screen for that board/point. Each point will increase incrementally to correspond with each board. (For example, where the MRLDS is address 1 and the MRLDS address is 100, use board 1, point 1. For an MRLDS address of 101, use point 2.) 4.4.
field to change the name, and press the down or right arrow to move to the (sensor) Type field. Use the “.” and “—” keys to scroll through the options and select IRLDS. (The Gain and Offset parameters are automatically configured for you.) 13. Use the arrow keys to move off the active fields and press 0 (zero) twice to go back to the main screen. 4.4.5 4.4.5.1 BEC and RMCC Controllers Less Than Version 2.1 Input Definitions Locate the screen in the BEC or RMCC where sensors are set up.
“MV” should be entered for sensor inputs that read fault status. 5 Diagnostics 5.1 MRLDS LED Indicators Gain and Offset Since the output terminals emit one volt for every 250 PPM of refrigerant detected, the gain for the refrigerant leak sensors must be set to 250 and the Offset to 0. The sensors configured to detect faults must be given a gain of 1000; this way, the REFLECS can be set up to alarm whenever it detects a 5000 mV signal. 4.4.5.
5.3 Linearity Settings for Supported Refrigerants Factors such as air movement and the proximity of the sensor to the leak will usually have a greater influence on the reading (Rdg) than the differences in the linearity (accuracy) of the various supported refrigerants, so the alarm limits should not have to be adjusted.
