Product Manual For Lake Flow Meters, Alarms and Transmitters www.lakemonitors.
This manual is a service guide produced by Lake Monitors and provides specific procedures and/or illustrations for disassembly, assembly, inspection, cleaning, and filtration. When followed properly, these procedures will keep your flow meter in top operating condition. It is important for operators and maintenance personnel to be safety conscious when operating or repairing equipment.
FLOW METERS www.lakemonitors.
Specifications Casing Material Aluminum, Brass or Stainless Steel #304 Maximum Pressure Aluminum and Brass: Stainless Steel #304: 3500 psi (240 Bar) 6000 psi (413 Bar) Maximum Temperature 240ºF (115ºC) Reading Direct Reading - 360º Ref. Line (Non-Electrical) Scale Accuracy +/- 4% FS, Center 1/3 of scale +/- 2.
Warning and Precautionary Areas 1) The meters are designed to operate in systems that flow in only one direction: the direction of the arrow on the flow scale. Attempting operation in the reverse direction may cause damage to the meter or other system components. 2) The window tube of standard meters is made of Lexan. Lexan can be safely cleaned with soap and water. However, many other cleaning agents can damage Lexan, causing discoloration or crazing.
INSTALLATION Basic Installation Instructions The meters are mounted in-line and are direct reading. The meters can be mounted in a vertical or horizontal position as long as the fluid is flowing in the direction of the arrow on the flow scale. No straight pipe is required before or after the meter. In fact, 90° elbows can be installed on both ends without any noticeable flow variation. When installing a meter, apply “Thread seal Tape” or “Liquid Thread Sealant” on pipe threads.
Fluid Flow in Reverse Direction The standard meter will not permit flow in the reverse direction (opposite direction to the arrow printed on the flow rate scale). In the reverse direction, the meter will behave in a manner similar to a leaky check valve. Prolonged flow in the reverse direction will cause damage to the standard monitor's internal mechanism that could result in inaccurate readings or premature failure of the meter.
OPERATION Operating Principles Lake has developed a line of unique flow meters which combine the simplicity of a sharp-edged orifice disk and a variable area flow meter. See Illustration 1 “Flow Meter Cross Section” on page 9. The meters are tubular, with all internal wetted parts sealed within the body casing. Running through the center of the body casing is a tapered center shaft which is centered in the bore by pilot disks at each end.
FLOW METER (CROSS SECTION) 3 5 4 Flow n ctio Dire 2 1 13 6 Flow n ctio Dire 7 8 9 10 12 11 Illustration 1 1. End Porting 8. Flowing Sharp-Edged Orifice Disk 2. Body Casing 9. Tapered Center Shaft 3. Magnet Follower 10. Transfer Magnet 4. Window Tube 11. Scale 5. Window Seal 12. Return Spring 6. Seal Assembly 13. Retainer Ring 7.
The indicated flow reading will read high for heavier fluids and low for lighter fluids. A corrective factor can be applied to the standard scale or a special scale can be added at a slight additional cost. When flowing other specific gravities, the basic equations below can be used. For WATER Meters use: 1.0/Specific Gravity x scale reading For OIL Meters use: .873/Specific Gravity x scale reading Viscosity Effect The meters incorporate a unique floating, sharp-edged orifice disk.
Measuring ranges cover 1.5-12 SCFM through 150-1300 SCFM. Twenty-four port sizes from 1/8" through 2" in NPT, SAE and BSP can be ordered to meet specific plumbing requirements. Lake’s pneumatic meters are also available in alarm and transmitter configurations for electronic monitoring applications. Standard Cubic Feet Lake’s meters are calibrated to measure the flow of compressible media (gases) in SCFM – standard cubic feet per minute.
DENSITY CORRECTION FACTORS SCFM (indicated) x (CF) = SCFM (Actual) CF = (f1) x (f2) X (f3) Note: all correction factors need not be used. Table 1. (f1) PRESSURE CORRECTION FACTORS (inlet pressure) psig 25 f1 .56 50 75 100 125 150 175 200 .75 .88 1.0 1.11 1.2 1.29 1.37 f1 = 14.7 + psig 114.7 Table 2. (f2) TEMPERATURE CORRECTION FACTORS ºF f2 10º 30º 50º 70º 90º 110º 130º 150º 1.08 1.04 1.02 1.0 .98 .96 .95 f2 = .93 530 460 + ºF Table 3.
Selecting the Proper Meters To order a pneumatic flow meter the following information is required: n pipe size and port style n media (air, nitrogen, argon,etc.) – for material compatibility and specific gravity considerations n approximate flow range required1 n system pressure: nominal, maximum, minimum n system temperature Flow Range1 Estimating the flow rate in a compressed gas system may seem complicated, but with some research and a few simple equations an educated guess can be made.
TROUBLESHOOTING & MAINTENANCE TROUBLESHOOTING CHART Malfunction: Magnet follower sticks in mid-scale and will not return to the “no flow” position. Possible Cause: Corrective Action: Horizontal/Vertical Mount Particulate, Thread seal tape, rust or other foreign matter is holding the internal parts form returning. Disassemble and inspect meter for contamination. Install proper filtration or problem may reoccur.
TROUBLESHOOTING CHART (CONTINUED) Malfunction: Window tube is cracking or crazing. Possible Cause: Corrective Action: Using incompatible cleaning solution on Lexan window tube. Use soap & water or a mild degreaser (Stoddard or Naptha) to clean Lexan tube. To check the compatibility of your cleaning fluid, call General Electric’s Lexan Compatibility Reference line at 800-845-0600. Malfunction: Scale is fogging or coming loose.
Disassembly Important: It is not necessary to remove window tube or window seals to clean the meter. Note also how the meter disassembles for easy of reassembly. Warning: Shut down system before removing meter from flow line. 1. Use a clean dry cloth to remove all foreign material from exterior of meter, especially around threaded ends. Illustration 3 2. Remove meter from the flow line. 3. With the arrow on the scale pointing upward, mount the meter in a vice. See Illustration 3.
IMPORTANT: If inner cartridge does not slide out freely, it may be sign of contamination. The transfer magnet is a powerful ALNICO magnet. Keep it away from metal chips and fillings. They may be hard to remove when reassembling and will cause premature failure. 7. Examine inner cartridge or level of contamination. A. If inner cartridge has a low level of contamination and is functioning properly, no further disassembly is required. Proceed to “Cleaning and Inspection.” See Illustration 5. B.
Cleaning and Inspection Note: If the inner cartridge is damaged or contaminated beyond repair, the complete meter can be sent to the manufacturer for evaluation. The manufacturer will inspect, repair, and/or replace parts as needed according to the warranty. 1. Inspect inner cartridge and body casing for contamination. If the inner cartridge did not slide out freely, it may be a sign of contamination.
FILTRATION AND CONTAMINATION Recommended Filtration The manufacturer recommends system filtration of at least 74 micron filter or a 200 mesh screen. It has been found that if inadequate filtration has caused meter failure, it will normally fail in the open position. Some systems may require a magnetic filter. IMPORTANT: Meter damage caused by excessive contamination is not covered under warranty. Stabilized Contamination The goal of filtration is to create effective protection from system contamination.
Self-Generation Contamination Self-generated contamination is a product of wear, cavitation, fluid breakdown and corrosion. Systems that are carefully flushed, maintained, and have fresh fluid added, mainly have self-generated contamination. In this case, proper filtration can prevent fluid component malfunction.
FLOW ALARMS www.lakemonitors.
NOTE: Installation, operation and cleaning instructions for the basic flow meter cartridge can be found in the first section of this manual. The following instructions are specifically for meters with electrical switches for flow alarms. General Information Lake’s Flow Alarms are typically used to make or break a set of electrical contacts to signal a limit setting. They may be used to turn on a warning light, sound a bell or horn, or even to shut down a process.
The pointer indicates the set point for the alarm switch. In Illustration 1, the switch will be actuated at all flow rates below 4 GPM. To change the set point, simply loosen the switch glide screw one (1) turn and slide the switch to the desired position along the flow rate scale. When the pointer is pointing to the desired flow rate, re-tighten the switch glide screw.
Switches Specifications Type Form C, dry contact UL/CSA Rating 10 & 1/4 hp, 125 or 250 VAC 1/2 A, 125 VDC & 1/4A, 250 VDC 3A, 125 VAC “L” lamp load Mechanical Life >10,000,000 cycles Actuating Mechanical Simulated roller, lever operated, low force Connectors 3/16" tab Double Break Switch (Special) Form Z - 10A &1/2hp, 125/250 VAC Electrical Connections Standard Flow Alarms are pre-wired with 4pin Hirschmann-type DIN connectors which consist of a male section as shown in Illustration 4 and the Il
Illustration 7 shows the connections for a standard, single switch Flow Alarm as they are shipped from the factory. The wiring for other types of connections are outlined in the tables below. For additional details, please consult the factory or your authorized Lake distributor. Alternates to the standard Hirschmann-type DIN connector are available on a custom basis.
Standard Control Circuits Page 26 / Flow Alarms / Lake Manual
* The load must be within the flow alarm’s and the slave relay’s contact rating. Please see specifications.
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FLOW TRANSMITTERS www.lakemonitors.
NOTE: Installation, operation and cleaning instructions for the basic flow meter cartridge can be found in the first section of this manual. The following instructions are specifically for meters equipped with signal conditioning circuitry for transmitting a proportional output signal. General Information Lake’s Flow Transmitters are typically used to transmit a signal proportional to flow rate to a process control computer, a PLC, a recorder, or a panel-mount display.
The sensor array located in the sensor assembly sends a signal relative to the position of the follower to the signal conditioning circuit. The signal conditioning circuit converts the signal from the sensor array into three different signals that are all directly proportional to the reading that is determined by relating the position of the flow indicator line to the flow rate scale.
NO CONNECTION PIN #1 +12 - 35 VDC PROGRAMMABLE JUMPER IN POSITION CLOSEST TO METER OUTLET PIN #2 4 - 20 m A OUT NO CONNECTION ELECTRICAL CONNECTION - 4-20 mA JUMPER POSITION - 4-20 mA Illustration 2 Illustration 3 4-20 mA Output Connections Wiring Instructions (Refer to Illustrations 2 and 3 above): 1) Move the programmable jumper on the signal conditioning board into the position closest to the meter’s outlet, as shown in Illustration 3.
NO CONNECTION PROGRAMMABLE JUMPER IN POSITION CLOSEST TO METER INLET PIN #1 +12 - 35 VDC PIN #2 DC GROUND PIN #3 0 - 5 VDC OUTPUT ELECTRICAL CONNECTIONS - 0 - 5VDC JUMPER POSITION - 4-20 mA Illustration 4 Illustration 5 0-5 VDC Output Connections Wiring Instructions (Refer to Illustrations 4 and 5 above): 1) Move the programmable jumper on the circuit board into the position closest to the meter’s inlet, as shown in Illustration 5.
“G” PIN 0-2000Hz OUTPUT PROGRAMMABLE JUMPER IN POSITION CLOSEST TO METER INLET PIN #1 +12 - 35 VDC PIN #2 DC GROUND NO CONNECTION ELECTRICAL CONNECTIONS - 0-2000Hz OUTPUT JUMPER POSITION - 0-2000Hz PULSE OUTPUT Illustration 6 Illustration 7 0-2000 Hz Pulse Output Connections Wiring Instructions (Refer to Illustrations 6 and 7 above): 1) Move the programmable jumper on the circuit board into the position closest to the meter’s inlet, as shown in Illustration 7.
NO CONNECTION PIN #2 1-5 VDC OUT PROGRAMMABLE JUMPER IN POSITION CLOSEST TO METER OUTLET PIN #1 +17 - 35 VDC 249 OHMS NO CONNECTION TO SIGNAL GROUND ELECTRICAL CONNECTIONS - 1- 5 VDC JUMPER POSITION - 1- 5 VDC Illustration 8 Illustration 9 1-5 VDC Output Connections Wiring Instructions (Refer to Illustrations 8 and 9 above): 1) Move the programmable jumper on the signal conditioning board into the position closest to the meter’s outlet, as shown in Illustration 9.
Connectors Standard flow sensors are prewired with 4-wire Hirschmann-type DIN connectors which consist of a male section as shown in Illustration 10 and a female section as shown in Illustration 11. In order to make the user connections, the screw terminals located inside of the female section must be accessed. To open the female section, first remove the screw and then lift the connector portion out of the casing by inserting the head of a screwdriver into the slot marked for that purpose.
User Adjustments The 4-20 mA, 0-5V, and 0-2000 Hz square wave outputs on the Lake Monitors Flow Transmitter are all factory calibrated. User adjustment should be unnecessary and any adjustment of the potentiometer on the signal conditioning board is strongly discouraged. If one of the outputs does fall out of calibration, the following procedure may be used to recalibrate the unit. 1) Turn off the flow through the system. 2) Connect between +12 and +35 VDC to pin 1 of the din connector.
12) Gradually increase the flow through the system until the flow rate indicated on the printed flow rate scale reaches full-scale (the highest value printed on the scale). 13) Adjust the 4-20 mA span potentiometer (see Illustration 1) until a reading of 20.00 mA is obtained on the ammeter. 14) Gradually decrease the flow through the system until a value equal to 50% of full-scale is obtained on the sensor’s flow rate scale. Verify a reading of between 11.92 and 12.08 mA.
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For downloadable product manuals, data sheets and CAD drawings, visit Lake’s web site today! www.lakemonitors.com LAKE MONITORS 8809 INDUSTRIAL DRIVE, FRANKSVILLE, WI 53126 P: (800) 850-6110 (262) 884-9800 F: (262) 884-9810 WWW.LAKEMONITORS.COM LCM-505 Rev. 5.24.12 ©2005 Lake Monitors.
