Reverse Rotation Protection; Oil Failure Protection; Dip Switch Settings; Ipc Address - Trane RTAA-70 Installation & Maintenance Manual

100
Controls Interface
( )
l + l + l
1 2 3
l = ----------------------------- -
ave
3
1
= phase with greatest difference from lave (without regard to sign)
x
If Phase Unbalanced Protection (Service Settings Menu) is enabled, and the
average three phase current is greater than 80% RLA, and the percent of
imbalance is calculated to exceed 15%, the UCM will shutdown the
compressor and display a CMR diagnostic.
In addition to the 15% criteria, the Clear Language Display has a non-
defeatable 30% criteria which has its own diagnostic. If the 15% criteria is
enabled, it will always display the 15% diagnostic first. The 30% criteria is
always active when a compressor is running, regardless of% RLA.

Reverse Rotation Protection

The Clear Language Display monitors incoming current during start-up and
will shutdown the compressor within one second, if phase reversal is
detected.
CAUTION
Reversed Phase Rotation!
Phase relationships during installation of unit power must be
carefully controlled to assure compressor protection against
reversed phase rotation.

Oil Failure Protection

The 70 to 125 Ton units do not use the differential pressure switch to monitor
for an oil line restriction. The logic of the UCM uses a comparison of the
entering oil temperature at the compressor to the saturated condenser
temperature to determine if there is an oil line restriction.
The differential between the entering oil temperature and the saturated
condenser temperature is referred to as the" Oil Loss Differential Setpoint" in
the Service Settings Menu. This setpoint must remain at the default of -4 F
for the unit to function properly.
If the entering oil temperature drops 4 F below the saturated condenser
temperature for more than 30 minutes, the circuit will shutdown on a CMR
diagnostic. The diagnostic will be presented as:

DIP Switch Settings

Compressor Overload DIP Switches
The settings for these switches are shown in Table 18.

IPC Address

The IPC address set the address for Inter-Processor Communications of the
Clear Language Display modules. The following is the IPC DIP switch settings
for the RTAA 70 – 125 modules.
MODULE
IPC DIP
SWITCH 1U3 1U4
1 OFF OFF
2 OFF OFF
3 — —
"OIL SYSTEM FAULT - CKT X°
1U5 1U7
OFF OFF
ON OFF
— ON
RTAA-SVX01A-EN