Installation and Maintenance Manual

Diagnostics
11 6 RTAC-SVX01M-EN
Communication Diagnostics
The following communication loss diagnostics will not
occur unless that input or output is required to be present
by the particular configuration and installed options for
the chiller.
Communication diagnostics (with the exception of
“Excessive Loss of Comm” are named by the Functional
Name of the input or output that is no longer being heard
from by the Main Processor. Many LLIDs, such as the Quad
Relay LLID, have more than one functional output
associated with it. A comm loss with such a multiple
function board, will generate multiple diagnostics. Refer to
the Chiller's wiring diagrams to relate the occurrence of
multiple communication diagnostics back to the physical
LLID boards that they have been assigned to (bound).
Starter Panel High
Temperature Limit -
Panel 2, Cprsr 2B
Cprsr 2B
Special
Mode
NonLatch All
Starter Panel High Limit Thermostat (170 F) trip was detected.
Note: Other diagnostics that may occur as an expected
consequence of the Panel High Temp Limit trip will be
suppressed from annunciation. These include Phase Loss, Power
Loss, and Transition Complete Input Open for Cprsr 2B
Local
Suction Refrigerant
Pressure Transducer
- Circuit 1,
Compressor 1A
Special Immediate Latch All
Bad Sensor or LLID Circuit target if no isolation valves,
Compressor target if isolation valves. Design Note: In the case
of manifolded compressors w/o isolation valves, the occurrence
of this diagnostic will also generate a comm loss with the
nonexistent Suction Press Cprsr 1B in order to accomplish circuit
shutdown.
Remote
Suction Refrigerant
Pressure Transducer
- Circuit 1,
Compressor 1B
Cprsr 1B Immediate Latch All
Bad Sensor or LLID. Design Note: For circuits with manifolded
compressors w/o isolation valve option, this diagnostic will occur
with the preceding diagnostic, even though this transducer is not
required or installed.
Remote
Suction Refrigerant
Pressure Transducer
- Circuit 2,
Compressor 2A
Special Immediate Latch All
Bad Sensor or LLID Circuit target if no isolation valves,
Compressor target if isolation valves. Design Note: In the case
of manifolded compressors w/o isolation valves, the occurrence
of this diagnostic will also generate a comm loss with the
nonexistent Suction Press Cprsr 2B in order to accomplish circuit
shutdown.
Remote
Suction Refrigerant
Pressure Transducer
- Circuit 2,
Compressor 2B
Cprsr 2B Immediate Latch All
Bad Sensor or LLID. Design Note: For circuits with manifolded
compressors w/o isolation valve option, this diagnostic will occur
with the preceding diagnostic, even though this transducer is not
required or installed
Remote
Very Low Evaporator
Refrigerant Pressure
- Circuit 1
Chiller Immediate Latch
All
[compressor or
circuit in manual
lockout]
The evaporator pressure dropped below 8 psia (or 5 psia in sftw
prior to Oct '02)regardless of whether or not compressors are
running on that circuit. This diagnostic was created to prevent
compressor failures due to cross binding by forcing an entire
chiller shutdown. If a given compressor or circuit is locked out,
the suction pressure transducer(s) associated with it, will be
excluded from causing this diagnostic.
Local
Very Low Evaporator
Refrigerant Pressure
- Circuit 2
Chiller Immediate Latch
All
[compressor or
circuit in manual
lockout]
The evaporator pressure dropped below 8 psia (or 5 psia in sftw
prior to Oct '02) regardless of whether or not compressors are
running on that circuit. This diagnostic was created to prevent
compressor failures due to cross binding by forcing an entire
chiller shutdown. If a given compressor or circuit is locked out,
the suction pressure transducer(s) associated with it, will be
excluded from causing this diagnostic.
Local
Table 67. Main processor diagnostics (continued)
Diagnostic Name
Affects
Target Severity
Persist-
ence
Active Modes
[Inactive
Modes] Criteria
Reset
Level
Table 68. Communication diagnostics
Diagnostic Name
Affects
Target Severity
Persist-
ence
Active
Modes
[Inactive
Modes] Criteria
Reset
Level
Comm Loss: Chilled
Water Flow Switch
Chiller Immediate Latch All
Continual loss of communication between the MP and the
Functional ID has occurred for a 30 second period.
Remote
Comm Loss: Cond Rfgt
Pressure, Circuit #1
Circuit Immediate Latch All
Continual loss of communication between the MP and the
Functional ID has occurred for a 30 second period.
Remote
Comm Loss: Cond Rfgt
Pressure, Circuit #2
Circuit Immediate Latch All
Continual loss of communication between the MP and the
Functional ID has occurred for a 30 second period.
Remote