Lochinvar MP2, INS7141, INS7162, TST2313 installation instructions Dc or 0 20 mA, Dc or 4 20 mA

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INPUT SIGNAL

EXTERNAL INPUT SIGNAL CONVERSION TABLES

The control can accept either a 0 - 10 V (dc) signal or a 2 - 10 V (dc) signal. The External Input Signal setting must be set to the proper setting based on the signal that is being sent to the control.

0 - 10 V (dc) or 0 - 20 mA

When the 0 - 10 V (dc) signal is selected, an input voltage of 1 V (dc) corresponds to a boiler target temperature of 50°F (10°C). An input voltage of 10 V (dc) corresponds to a boiler target temperature of 210°F (99°C). As the voltage varies between 1 V (dc) and 10 V (dc) the boiler target tem- perature varies linearly between 50°F (10°C) and 210°F (99°C). If a voltage below 0.5 V (dc) is received the boiler target temperature is displayed as " - - - " indicating that there is no longer a call for heating.

A 0 - 20 mA signal can be converted to a 0 - 10 V (dc) sig- nal by installing a 500 ohm resistor between the Out + and Com - terminals (4 and 1).

2 - 10 V (dc) or 4 - 20 mA

When the 2 - 10 V (dc) signal is selected, an input voltage of 2 V (dc) corresponds to a boiler target temperature of 50°F (10°C). An input voltage of 10 V (dc) corresponds to a boiler target temperature of 210°F (99°C). As the voltage varies between 2 V (dc) and 10 V (dc) the boiler target tem- perature varies linearly between 50°F (10°C) and 210°F (99°C). If a voltage below 1.5 V (dc) is received the boiler target temperature is displayed as " - - - " indicating that there is no longer a call for heating.

A 4 - 20 mA signal can be converted to a 2 - 10 V (dc) sig- nal by installing a 500 ohm resistor between the Out + and Com - terminals (4 and 1).

OFFSET

The Offset setting allows the boiler target temperature to be fine tuned to the external input signal. The control reads the external input signal and converts this to a boiler target tem- perature. The Offset setting is then added to the boiler tar- get temperature.

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Contents Installation Instructions Additional Functions IncludeTable of Contents Display Boiler Reset Stand Alone Section a General OperationDomestic Hot Water Set PointAlarm Boiler AlarmCombustion Air C. a Fixed Lead RotationResetting the Rotation Sequence Resetting the Running TimesSection B Staging Operation ModeLo / Hi Fire DelayLo / Lo Section C Pump Operation MedFixed Differential Auto DifferentialSection D Boiler Reset Operation Boiler Pump PurgeType of terminal unit. This improves the control of the air High Mass Radiant Section E Domestic HOT Water OPERA- Tion DHW DemandDHW Mode 4 DHW in Primary / Secondary with Priority Section F SET Point Operation Setp Mode 1 Setpoint in Parallel Section G External Input OperationDc or 0 20 mA Dc or 4 20 mAAc Power GeneralBoiler Demand DHW DemandCombustion Air / Alarm Contact C.A./Alarm Set Point DemandExternal Input 0 10 V dc Primary Pump Contact Prim P1UnOccupied Switch Relay 9 / DHWBoiler Return Sensor Boiler Supply SensorExternal Input Combustion Air or Alarm C.A. / Alarm Primary Pump Prim P1Cleaning the Control GeneralRotate / OFF Page Page Page Stage Delay DHW ModeBoiler Minimum Boiler MaximumThis item is only available when DHW Mode is set to OFF Testing the Control Error Messages Technical Data Is not a safety limit controlTypical Boiler Installation Typical Boiler Installation Typical DWH Priority Heating Package System