Trane CVHE Troubleshooting

CVHE-SB-32A 56
External Chilled Water Setpoint
The External Chilled Water Setpoint allows a customer to change the chilled water setpoint from
a remote location. The External Chilled Water Setpoint is found on Options module terminals J9-
4 and J9-5.
UCP2 accepts either a 2-10 VDC or 4-20 mA analog input suitable for customer connection to set
the unit leaving chilled water setpoint. 2-10 VDC and 4-20 mA shall each correspond to a 0 to
65°F (-17.8 to 18.3°C) CWS range. For input signals beyond the 2-10 VDC or 4-20 mA range, an
information diagnostic is called and the active chilled water setpoint will default to the front panel.
UCP2 uses the following equations:
The following graph shows External Chilled Water Setpoint with a 4-20 mA input:
Voltage Signal Current Signal
As generated from external source VDC=.12308*(°F)+2 mA=.24615(°F)+4
As processed by UCP2 °F=8.125*(VDC)-16.25 °F=4.0625(mA)-16.25
External Chilled Water Setpoint with (ma) Input
-20.00
-10.00
0.00
10.00
20.00
30.00
40.00
50.00
60.00
70.00
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
ma
Degrees
Degrees F
Degrees C
Degrees F
Degrees C

Trane CVHE Specifications

General

Brand	Trane
Model	CVHE
Category	Chiller
Language	English