Diagnostics
78
RTAF-SVX001K-EN
AFD Diagnostics
Table 31. AFD diagnostics
Diagnostic Name and
Source
Affects
Target
Severity
Persistence
Active Modes
[Inactive
Modes]
Criteria
Reset
Level
AFD Fault - xA
Cprsr
Immediate
NonLatch
All
AFD Fault. Numerous drive faults can cause
this general fault including High Pressure
Cutout for AFD compressors.
Local
AFD Motor Current Overload - xA Circuit
Immediate
Latch
All
Compressor current exceeded overload time
vs. trip characteristic. Must trip = 132%
RLA, Must hold=125%
Local
AFD Interrupt Failure - xA
Chiller
Immediate
Shutdown and
Special Action
Latch
AFD Intended to
be OFF
Respective AFD is reporting that it is still
running the compressor when the MP has
commanded the drive/compressor to be Off.
Detection time shall be 10 seconds minimum
and 15 seconds maximum. On detection and
until the controller is manually reset: this
diagnostic shall be active and the alarm relay
shall be energized, the Evap Pump Output
will be energized, the effected compressor
will be continually commanded off, and be
unloaded, while a normal stop shall be
commanded to all other compressors. For
as long as compressor operation continues,
the MP shall continue oil return and fan
control on the circuit affected. During
contactor interrupt failure, circuit will not be
confirmed off, so THR unit sequence should
continue running. If THR turns off due to a
diagnostic or lockout during contactor
interrupt failure, the circuit reverts to air-
cooled condenser fan control within 1
second.
Local