User Guide

Application guidelines
23AB237986441643en-US0701
If any thermistor exceeds its response
temperature, its resistance increases above the
trip level (4,500 Ω) and the output relay then trips
-ie. contacts M1-M2 are open. After cooling to
below the response temperature (resistance <
2,750 Ω), a 5 minute time delay is activated. After
this delay has elapsed, the relay is once again
pulled in ie. contacts M1-M2 are closed. The time
delay may be cancelled by means of resetting the
mains (L-N disconnect) for approximately 5 sec.
A red/green twin LED is visible on the module.
A solid green LED denotes a fault free condition.
A blinking red LED indicates an identiable fault
condition:
Phase sequence and reverse
rotation protection
Use a phase meter to establish the phase
orders and connect line phases L1, L2 and L3
to terminals T1, T2 and T3, respectively. The
compressor will only operate properly in a single
direction, and the motor is wound so that if the
connections are correct, the rotation will also be
correct.
Compressor model SM112-124-147 have no
internal reverse rotation protection. If reverse
rotation occurs it will be obvious as soon as
power is turned on. The compressor will not
build-up any pressure, the sound level will be
abnormally high and power consumption will be
minimal. In such case, shut down the compressor
immediately and connect the phases to their
proper terminals. Prolonged reverse rotation will
damage the compressor.
A phase sequence detector is strongly
recommended.
Compressor models SM / SZ 084 to 185 (except
SM112-124 & 147) incorporate an internal reverse
vent valve which will react in the presence of
reverse rotation and will allow refrigerant to
circulate through a by-pass from the suction to
the discharge. Although reverse rotation is not
destructive, even over long periods of time up
to several days it should be corrected as soon
as possible. Reverse rotation will be obvious
to the user as soon as power is turned on; the
compressor will not build up any pressure, the
sound level will be abnormally high and power
consumption will be minimal. If reverse rotation
symptoms occur, shut the compressor down and
connect the phases to their proper terminals. If
reverse rotation is not halted, the compressor will
cycle o on the internal motor protection.
PTC overheat
Appr. 1 second
Delay timer active (after PTC overheat)
Appr. 1 second
40ms 40ms460ms 460ms
920ms80ms
Electrical data, connections and wiring