Electrical data, connections and wiring
Motor protection
CH Compressor models are delivered with a
pre-installed motor protection module inside the
terminal box. This device provides for efficient
and reliable protection against overheating and
overloading as well as phase loss/reversal.
The motor protector comprises a control module
and PTC sensors embedded in the motor
winding. The close contact between thermistors
and windings ensures a very low level of thermal
inertia.
The motor temperature is being constantly
measured by a PTC thermistor loop connected
on S1-S2. If any thermistor exceeds its response
temperature, its resistance increases above the
trip level (4,500 Ω) and the output relay then
trips – i.e. 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 – i.e. contacts M1-M2 are closed.
The time delay may be cancelled by means
of resetting the mains (L-N -disconnect) for
approximately 5 sec.
When present, the LED on module will lighten as
follows in case of overheat:
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 CH290 & CH485 are delivered
with an electronic module which provides
protection against phase reversal and phase
loss at start-up. Apply the recommended wiring
diagrams from section “Suggested wiring
diagram logic”. The circuit should be thoroughly
checked in order to determine the cause of the
phase problem before re-energizing the control
circuit. The phase sequencing and phase loss
monitoring functions are active during a 5-sec
window 1 second after compressor start-up
(power on L1-L2-L3).
Should one of these parameters be incorrect,
the relay would lock out (contact M1-M2 open).
When present, the led on the module will show
the following blink code:
Phase sequence and reverse
rotation protection
Vavg = Mean voltage of phases 1, 2, 3.
V1-2 = Voltage between phases 1 and 2.
V1-3 = Voltage between phases 1 and 3.
V2-3 = Voltage between phases 2 and 3.
| Vavg - V1-2 | + | Vavg - V1-3 | + | Vavg - V2-3 |
2 x Vavg
% voltage
imbalance =
x 100
The operating voltage limits are shown in the
table section “Motor voltage”. The voltage applied
to the motor terminals must lie within these
table limits during both start-up and normal
operations. The maximum allowable voltage
imbalance is 2%. Voltage imbalance causes high
amperage over one or several phases, which in
turn leads to overheating and possible motor
damage. Voltage imbalance is given by the
formula:
Voltage imbalance
PTC overheat
Delay timer active (after PTC over temp.)
Appr. 1 second
40ms
40ms
460ms
460ms
Appr. 1 second
920ms
80ms
Compressor
start
Phase monitoring
0 1 s 6 s
Phase sequence module logic
The lockout may be cancelled by resetting the
power mains (disconnect L-N) for approximately
5 seconds.
In case of phase reverse error:
In case of phase loss error:
Appro. 760 ms
120 ms120 ms120 ms
400ms
Appr. 1second
500ms
500ms
17
FRCC.PC.026.A4.02
Application Guidelines
