Mitsubishi Heavy Industries SRRM40HENG-L, Handbook, Page: 332 / 1106

330
FDT(N)-H
(ii) If 60 minutes passes and the detected temperature after the first to the fourth stoppage is not less than 90
°
C, an
abnormal stop of the unit is performed.
Note (1) Once an abnormal discharge temperature has occurred, restarting cannot be performed for 45 minutes. [De-
tection temperature less than 3
°
C]. (In failure mode, resetting cannot be performed by remote control.)
Operation is possible after 45 minutes. (Cleared by resetting power source.)
d) Cooling overload protection
State of overload during cooling operation is detected (with Tho-R) based on the temperature of outdoor heat exchanger and
the unit operation is stopped / Immediate reset after repair
60
°
C
Outdoor heat exchanger temp.
70
°
C
Error stop
Operable
e) Thermistor [Discharge piping (Only case of FDC(P)208~508 type), Heat exchanger and outdoor air ther-
mistor] disconnected wire
(i) If there is a disconnected wire or if there is a big difference in performance characteristics, an abnormal stop of the unit is
performed.
e
Restore after repairing.
5) Compressor protecting function (Microcomputer and phase protection relay)
a) Overcurrent control
(i) When a 52C secondary L
1
-phase continues for 0.5 seconds and when it is more than the set value (detection at current
sensor CT), the compressor is stopped. The compressor is restarted after a 3-minute delay if the detection current is less
than 1.5 to 2A. If this condition is re-detected 5 times within 60 minutes of the first occurrence, an abnormal stop of the
unit is performed.
(ii) If 60 minutes passes and the detected current after the first to the fourth stoppage is not less than 1.5~2A, an abnormal
stop of the unit is performed.
b) Open-phase protection
When a 52C secondary detection current continues for 4 seconds when the compressor is on and when it is less than 1.5 to 2
A, it is determined to be a open-phase of the 52C secondary N-phase, and the compressor is stopped. The compressor is
restarted after a 3-minute delay and if this condition is re-detected within 60 minutes of the first occurrence, an abnormal stop
of the unit is performed.
c) Detection of abnormal discharge temperature (Only case of FDC(P)208~508 type)
(i) When an abnormally high temperature is detected at the discharge pipe of the compressor (Tho-D detection), the
compressor is stopped. The compressor is restarted after a 3-minute delay and if this condition is re-detected 5 times
within 60 minutes of the first occurrence, an abnormal stop of the unit is performed.
90
Discharge pipe temp. (
°
C)
135
Error stop
Operable