Filter
Top Products
RTAC-SVX01F-EN 77
Installation - Electrical
CAUTION
Heat Tape!
Control panel main processor does not check for loss of power to the
heat tape nor does it verify thermostat operation. A qualified technician
must verify power to the heat tape and confirm operation of the heat
tape thermostat to avoid catastrophic damage to the evaporator.
A convenience outlet is also optional, which shares the same power supply as the
heaters on 140-250 ton units. Be aware that when the heater is operating, the
convenience outlet amperage draw will be reduced accordingly.
NOTE: The convenience outlet is optional. The heaters are required.
Interconnecting Wiring
Chilled Water Flow (Pump) Interlock
The Model RTAC Series R
®
chiller requires a field-supplied control voltage contact
input through a flow proving switch 5S1 and an auxiliary contact 5K1 AUX. Connect
the proving switch and auxiliary contact to 1TB5-8 and 1U11 J3-2. Refer to the field
wiring for details. The auxiliary contact can be BAS signal, starter contactor auxiliary.
or any signal which indicates the pump is running. A flow switch is still required and
cannot be omitted.
Chilled Water Pump Control
An evaporator water pump output relay closes when the chiller is given a signal to go
into the Auto mode of operation from any source. The contact is opened to turn off
the pump in the event of most machine level diagnostics to prevent the build up of
pump heat.
CAUTION
Evaporator Damage!
IMPORTANT: ALL unit chilled water pumps must be controlled by the
Trane CH530 to avoid catastrophic damage to the evaporator due to
freezing. Refer to RLC-PRB012-EN.
The relay output from 1U10 is required to operate the Evaporator Water Pump (EWP)
contactor. Contacts should be compatible with 115/240 VAC control circuit. The EWP
relay operates in different modes depending on CH530 or Tracer commands, if
available, or service pumpdown (See maintenance section). Normally, the EWP relay
follows the AUTO mode of the chiller. Whenever the chiller has no diagnostics and is
in the AUTO mode, regardless of where the auto command is coming from, the
normally open relay is energized. When the chiller exits the AUTO mode, the relay is
timed open for an adjustable (using TechView) 0 to 30 minutes. The non-AUTO modes
in which the pump is stopped, include Reset (88), Stop (00), External Stop (100),
Remote Display Stop (600), Stopped by Tracer (300), Low Ambient Run Inhibit (200),
and Ice Building complete (101).
Regardless of whether the chiller is allowed to control the pump on a full-time basis, if
the MP calls for a pump to start and water does not flow, the evaporator may be
damaged catastrophically. It is the responsibility of the installing contractor and/or
the customer to ensure that a pump will start when called upon by the chiller
controls.