Trane CCUN 205-211 Network Card User Manual


 
Diagnostics
CG-SVU02B-E434
Programmable Relays
(Alarms and Status)
CH530 provides a flexible alarm or
chiller status indication to a remote
location through a hard wired
interface to a dry contact closure.
Four relays are available for this
function, and they are provided
(generally with a Quad Relay Output
LLID) as part of the Alarm Relay
Output Option.
The events/states that can be
assigned to the programmable
relays are listed in the following
table and through a TechView
configuration.
Event/state Description
Alarm - Latching This output is true whenever there is any active diagnostic that requires a manual reset to clear, that affects the chiller, the
circuit, or any of the compressors on a circuit. This classification does not include informational diagnostics.
Alarm - Auto reset This output is true whenever there is any active diagnostic that could automatically clear that affects the chiller, the circuit or
any of the compressors on a circuit. This classification does not include informational diagnostics. If all of the auto resetting
diagnostics were to clear, this output would return to a false condition.
Alarm This output is true whenever there is any diagnostic affecting any component, whether latching or automatically clearing. This
classification does not include informational diagnostics.
Warning This output is true whenever there is any informational diagnostic affecting any component, whether latching or automatically
clearing.
Chiller Limit Mode This output is true whenever the chiller has been running in one of the Unloading types of limit modes (Condenser,
Evaporator, Current Limit or Phase Imbalance Limit) continuously for the last 20 minutes. A given limit or overlapping of
different limits must be in effect continuously for 20 minutes prior to the output becoming true. It will become false, if no
Unload limits are present for 1 minute. The filter prevents short duration or transient repetitive limits from indicating. The
chiller is considered to be in a limit mode for the purposes of front panel display and annunciation, on if it is fully inhibiting
loading by virtue of being in either the "hold" or "forced unload" regions of the limit control, excluding the "limited loading
region". In previous designs, the "limit load" region of the limit control was included in the criteria for the limit mode call out
on the front panel and annunciation outputs.
Compressor Running The output is true whenever any compressors are started or running on the chiller and false when no compressors are either
starting or running on the chiller. This status may or may not reflect the true status of the compressor in Service Pumpdown
if such a mode exists for a particular chiller.
Maximum Capacity The output is true whenever the chiller has reached maximum capacity continuously for the Max Capacity Relay debounce
time. The output is false when the chiller does not have all its available compressors running continuously for the debounce
time.
Default setting Event/Status
Output relay 1 Compressor running
Output relay 2 Latching alarm
Output relay 3 Chiller limit mode
Output relay 4 Warnings
Table 8 - Chiller events/status descriptions
Table 9 - Default settings