Page 14
– Bulletin 100-50-5.1
ALARM
DESCRIPTION
CAUSE
SYSTEM ACTION
PSA
Pressure Sensor
Alarm
1. Voltage across terminals 33 and 34 less
than 0.3VDC
2. Voltage across terminals 33 and 34 greater
than 4.6VDC (System pressure greater than
operating range of transducer, set by
P
)
Note:
If
HPA
is set to
, then
PSA
for high
pressure will not activate.
Opens terminals 19 and 20 and
closes EEV (pumpdown) until proper
pressure input returns. Alarm is
generated and a voltage difference
will occur across terminals 11/12 (for
use with an external alarm relay)
tSA
vt
Temperature
Sensor Alarm
Voltage across terminals 31 and 32 is outside
of the normal range of the thermistor.
Normal ranges: 2K = 0.36VDC to 4.5VDC
3K = 0.39VDC to 4.9VDC
10K = 0.3VDC to 4.6VDC
98.6K = 0.36VDC to 4.8VDC
Note:
Display will show
60
if temperature
sensor is not installed.
Opens terminals 19 and 20 and
closes EEV (pumpdown) until proper
temperature input returns. Alarm is
generated and a voltage difference
will occur across terminals 11/12 (for
use with an external alarm relay)
SHA
Low Superheat
Alarm
System operates less than 2°F superheat for
the delay time set by
Sd
.
Will use
5H
parameter to close the
EEV quicker. Alarm is generated and
a voltage difference will occur across
terminals 11/12 (for use with an ex-
ternal alarm relay). Normal operation
will resume and alarm will clear once
system superheat reaches 2°F.
HSHA
High Superheat
Alarm
System operates more than 2°F above
SHSP
(setpoint) for the delay time set by
5d
.
If
5HF
is set to
: No system
response. Alarm is generated and a
voltage difference will occur across
terminals 11/12 (for use with an exter-
nal alarm relay).
If
5HF
is set to
n
: EEV drives to 0%
position. Alarm is generated and a
voltage difference will occur across
terminals 11/12. Note: A power cycle
is required to resume normal opera-
tion if h5HF is set to ‘on’ and the sys-
tem goes into high superheat alarm.
Table 4 - Alarm Actions
