Trane R Series, Installation Operation & Maintenance

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RLC-SVX07A-EN 121
Controls Interface
2-10 VDC/4-20 mA Input for External Chilled Water Setpoint (CWS) and
Current Limit Setpoint (CLS)
When either external CWS or external CLS is used on the optional Module
1U2, DIP switch SW1 positions 1 and/or 2 must be set to accommodate the
type of signal source the customer has chosen, either 2-10 VDC or 4-20 mA.
Position SW-1-1 sets 2-10 VDC/4-20 mA for external CWS. SW1-2 sets 2-10
VDC/4-20 mA for external CLS. The “OFF” setting configures the external
input for 2-10 VDC; the “ON” setting configures the external input for
4-20 mA.
Mechanical Control Settings
The settings for the High Pressure switch, Oil Pressure switch, and Winding
Thermostat are shown below:
Remote CLD Operation
With only few exceptions, operation of the Remote CLD is identical to the
unit's CLD. To ease the operation of the Remote CLD, additional displays have
been added. For example, if multiple unit operation is used, the following
display will be inserted as the second display of the setpoint group:
Modify Setpoints for Units X
“Press (+) (-) to change settings”
The Stop and Auto keys function in the same manner, but the following
hierarchy between the unit's Stop/Auto keys and the Remote CLD Stop/Auto
keys is as follows:
1. Local Stop will always override Local Auto, Remote Stop and
Remote Auto.
2. Local Auto will always override Local Stop, Remote Stop and
Remote Auto.
3. Remote Stop will override Local Auto and Remote Auto but not
Local Stop.
4. Remote Auto will override Local Auto and Remote Stop but not
Local Stop.
If an operator tries to start the unit from the Remote CLD after the Stop
command has been given at the unit CLD, the screen on the Remote CLD will
read:
“LOCAL STOP command at unit cannot be
overridden by this remote device”
Communication Failure
If a communication failure occurs between the Remote CLD and the unit's
CLD, the setpoints will remain the same but a diagnostic will occur at the
Remote CLD panel. The Remote display screen will read:
“No communication to Unit X”
Press (enter) to select new unit
IPC DIP
SWITCH MODULE
1U3 1U4 1 US 1U7
1 OFF OFF OFF OFF
2 OFF OFF ON OFF
3 — — — ON
CLOSE OPEN
Compressor Discharge High Pressure Switch – PSIG 300 ±20 405 ±7
Compressor Motor Winding Thermostat – F 181 221