Trane R Series, Installation Operation & Maintenance

Page: 67 / 188

RLC-SVX07A-EN 67
Installation - Electrical
Low Voltage Wiring
The remote devices described below require low voltage wiring. All wiring to
and from these remote input devices to the UCM, as described below in
Paragraphs
"Emergency Stop (Normal Trip) on Page" 67 through "Outdoor Air
Temperature Sensor on Page" 74 , are for RTWA and RTUA units only and
must be made with shielded, twisted-pair conductors. Be sure to ground the
shielding only at the Clear Language Display. Refer to the Section on
“Unit
Wiring” for the recommended conductor sizes.
NOTE: To prevent control malfunctions, do not run low voltage wiring (<30
V) in conduit with conductors carrying more than 30 volts.
Emergency Stop (Normal Trip)
The Clear Language Display provides auxiliary control for a customer
specified/installed latching trip out. When this customer-furnished remote
contact (5K18) is provided, the chiller will run normally when the contact is
closed. When the contact opens, the unit will trip off on a manually resettable
diagnostic. This condition requires manual reset at the chiller switch on the
front of the Clear Language Display.
To connect, first remove the jumper located between terminals 3 and 4 of
1U1TB1. Connect low voltage leads 513 and 514 to those terminals. Terminal
strip locations are shown in Section
“Unit Wiring” . Refer to the field diagrams
which are shipped with the unit.
Silver or gold-plated contacts are recommended. These customer furnished
contacts must be compatible with 12 VDC, 45 mA resistive load.
External Circuit Lockout - Circuit #1
The UCM provides for auxiliary control via a customer specified or installed
contact closure, for individual operation of Circuit #1. If the contact is closed,
the refrigerant circuit will not operate. The refrigerant circuit will run normally
when the contact is opened. This feature is used to restrict total chiller
operation, eg. during emergency generator operations.
External circuit lockout will only function if External Circuit Lockout (Service
Setting Menu) is enabled.
These customer-supplied contact closures must be compatible with 12 VDC,
45 mA resistive load. Silver or gold plated contacts are recommended.
To install, cut, strip and wire-nut existing wire loop #W7 on the J3 connector
of the 1U4 module to low voltage leads 45A and 45B. Connections are shown
in the field diagrams which are shipped with the unit.
External Circuit Lockout - Circuit #2
The UCM provides for auxiliary control vai a customer specified or installed
contact closure, for individual operation of Circuit #2. If the contact is closed,
the refrigerant circuit will not operate. The refrigerant circuit will run normally
when the contact is opened. This feature is used to restrict total chiller
operation, eg. during emergency generator operations.
External circuit lockout will only function if External Circuit Lockout (Service
Setting Menu) is enabled.
These customer-supplied contact closures must be compatible with 12 VDC,
45 mA resistive load. Silver or gold plated contacts are recommended.
To install, cut, strip and wire-nut existing wire loop #W4 on the J3 connector
of the 1U5 module to low voltage leads 46A and 46B. Connections are shown
in Section
“Refrigerant Charging” and in the field diagrams which are shipped
with the unit.