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TWLC - Tempered Water Logic Controller

The Intelligent Control

Summary of Contents for TWLC

Page 1: ...TWLC Tempered Water Logic Controller The Intelligent Control ...

Page 2: ...ual board for each stage maximizes redundancy Menu driven access and programming Fault history Up to 14 inputs Connect to on board computer Fully automatic temperature staging and chiller rotation New for 2009 Latest firmware revision V40 has new features and improved chiller protection ...

Page 3: ... boards can be networked together Only one keypad needed to control up to six chiller units Additional keypads can be added up to the number of units in the system Up to six heat and cool temperature set point stages Easy to use display keypad with menu driven screens Features ...

Page 4: ... delay on compressors Ability to monitor the control system locally or remotely via a computer a modem and a dedicated phone line Complete system fault logs with run time reference If network is lost each chiller operates independently When replacing a board an initializing routine automatically integrates the new board into the system Features cont d ...

Page 5: ...network cable integrity One display keypad hook up One serial port connection for computer or modem hook up for local or remote monitoring Six outputs Compressor Reversing Valve Circulating pump Seawater pump Immersion Heat Fault warning for external alarm i e light or buzzer The Board features and outputs ...

Page 6: ...TWLC Power Logic Board Removable Terminal Strip Removable E Prom Display cable Jack Computer or Modem Jack Network cable Jacks ...

Page 7: ... Cable CXP Cable Cables Used To Connect TWLC Control And Circuit Boards Use to connect keypad in same enclosure and network connections between boards Use to connect remote mounted keypad to circuit board ...

Page 8: ...sensor Loop water out temperature sensor Sea water out temperature sensor Flow switch Discharge pressure switch transducer Automatically recognizable Suction pressure switch transducer Automatically recognizable Compressor current transducer Common loop water supply temperature sensor ...

Page 9: ...e sensor Common sea water in temperature sensor Sea water pump current transducer Loop water pump current transducer Loop water pressure transducer Sea water pressure transducer Two additional auxiliary inputs future enhancements The Board inputs cont d ...

Page 10: ...eaters Only modes Fault light Indicates system faults Alarm buzzer Indicates system faults Up and Down buttons Changing parameter values and navigating through menu screens and items within a menu Enter button clearing a fault advancing to another menu screen and selecting an item Back button jump back to previous screen or condition Display Keypad ...

Page 11: ...Off Cool Heat RevCyc Heaters Activates compressors first when sea water is 38 F 3 33 C compressors turn off and immersion heaters turn on Heaters Only activates immersion heaters only Modes of Operation ...

Page 12: ...ch compressor or heater is on disabled or in sustained shutdown Displays which mode the system is operating Displays the common loop water supply temperature Displays the loop water return temperature System Screen ...

Page 13: ...p water temperature limits non adjustable Displays high and low refrigerant pressure limits non adjustable Displays sea water temperature limit adjustable Disable enable alarm buzzer Select heavy or light load temperature set points Restore all settings to factory default Clear information that are logged by the board password protected Initial Setup Displays how many chillers the control system r...

Page 14: ... chiller Input Output Log Displays compressor water pump heater and reversing valve run times Minimum and maximum loop water temperatures Minimum and maximum sea water temperatures Minimum and maximum high and low refrigerant pressures Minimum and maximum AC voltage Chiller On Off manually enable or disable a chiller Output Status displays board outputs on or off Main Menu cont d ...

Page 15: ...Water Flow Switch Improper In And Out Loop Water Temperature Differences On Each Chiller Loss Of System Network EPROM Errors Loop Water Pressure w optional upgrade Sea Water Temperatures w optional upgrade Sea Water Pressure w optional upgrade Suction Refrigerant Pressure w optional upgrade Discharge Refrigerant Pressure w optional upgrade Improper In And Out Sea Water Temperature Differences On E...

Page 16: ...and sea water pump 230VAC signal outputs to activate water pump triggers Does not include loop or sea water pump contactor Does not include a display keypad purchase separately Includes a 2 FT display keypad cable Compressor current transducer can be added inside the box Includes a 10 FT length 12 conductor control cable to hook up to a chiller unit Single Chiller Unit Control Panel Standard Featu...

Page 17: ...tdown after 3 faults Loop water high temperature limit 130 F 54 4 C Sustained shutdown after 3 faults Immersion heater loop water high temperature limit 150 F 65 5 C Sustained shutdown after 3 faults High discharge refrigerant pressure exceeded 426 PSI Sustained shutdown after 5 faults System Faults For Version 33 and Earlier Eproms ...

Page 18: ... limit In cool mode if temperature difference is 14 F 7 8 C or greater for 2 minutes the chiller goes into sustained shutdown In and Out Sea water temperature difference limit In cool mode if temperature difference greater than 16 F 8 9 C and less than 20 F 11 C for 5 minutes or greater than 20 F 11 C for 2 minutes the chiller will go into sustained shutdown System Faults For Version 33 and Earlie...

Page 19: ...sensor to monitor stage set points Common loop water supply sensor The system will continue to operate Sea water out sensor The system will continue to operate Sea water in sensor The system will continue to operate and will use the next available sea water in senor if available Immersion heater loop water sensor Will use next available immersion heater loop water sensor and system continue to run...

Page 20: ...e top of the plate coil This sensor is used to sense the Loop water low temperature limit Freeze sensor Sensor is marked Supply Common loop water return sensor Located on the water inlet pipe on the bottom of the plate coil The chiller cycles on it s set points by this sensor All chillers read off of the 1 chiller ...

Page 21: ...MTD Model Units Loop water out sensor Sensor is inserted in a well in the back of the plate coil on the top Sensor should be marked Supply Common loop water return sensor Sensor is inserted in a well in the back of the plate coil on the bottom ...

Page 22: ...ons For The New TWC Model Units Loop water out sensor Sensor is inserted in a well in the back of the plate coil on the bottom Common loop water return sensor Sensor is inserted in a well in the back of the plate coil on the top ...

Page 23: ...New TWC Model Units Loop water return Loop water out or supply Notice the arrow on the flow switch Units are plumbed backwards from standard units ...

Page 24: ...oop Sensors Location Common loop water supply sensor The sensor should be located on the supply line right after all the chillers are plumbed together The sensor should always be wired up to the 1 chiller board ...

Page 25: ...rent stages But before you leave the unit these checks should be made Go to the chiller status screen and scroll down to Loop Water Out to check the temperature at the outlet of the chiller barrel Also check the temperature difference from Loop Water Out and Com Loop Return Do not use the default screen Use the Chiller Status screen In cool mode the difference should be around 8 to10 F 4C 5 5C for...

Page 26: ...en 12 18 PSI in some installs with 30 tons and above may go to 20 psi max The discharge gauge should be double the suction pressure if installed Check for proper phase rotation on 3 phase pumps Check the common loop strainer if installed for trash or debris Water Flow Problems ...

Page 27: ...Check the individual strainer at the inlet of the chiller barrel for trash or debris Only on MTC or earlier models Water Flow Problems ...

Page 28: ...temperature of the outlet pipe First thing to check is to tighten all of the connections on the terminal strip on the circuit board Unplug sensor out of the wire harness and ohm it out per chart If sensor is bad borrow the common loop supply sensor to replace it till you get a new one Sensor is a negative temperature coefficient thermistor Resistance decreases with temperature increase ...

Page 29: ...for moisture and corrosion If plugs are not to bad clean with electronic contact cleaner and blow out with compressed air If corroded badly cut the plugs out and butt connect the wires and heat shrink Or replace harness with part s 4160051 chiller harness and 263200004 MPE harness ...

Page 30: ...k the Common Loop Return against the Loop Water Out and the Common Loop Supply temperatures 14F degree 8C split would be below Common Loop Return temp in the cool mode and above for heat mode Check to make sure all the sensors are in the correct location and are in good contact to the piping Check all the connections at the terminal strip at the circuit board Follow the previous procedures for a b...

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