1
/10.2015/
electric
EN
12.5 Electrical Options
Flashes Error
1x
Overload
2x
Excess temperature
3x
Phase reversal
4x
Phase loss / open load
5x
Phase imbalance
6x
Shorted thyristor
12.5.3 Compressor Softstart
This option consists of a softstart controller which is installed in the electrical cabinet and limits the current when the
compressor starts. In units with two compressors each compressor needs a softstart controller.
The control characteristic of the softstart controller can be modified by 16 dip switches.
Moreover the softstart controller includes an overload protection and devices to monitor the thyristor temperature,
the phase rotation, the existence of all phases, the phase balance and
to check all thyristors and load connections for shorts.
When an alarm is detected according to the above mentioned criteria
the alarm is indicated by a LED. The number of flashes indicates the
cause of error.
12.5.2 Second Power Supply
This option provides the connection of a second power supply. Both power supplies are switched on to the A/C unit.
A contactor circuit ensures that the priority is set on power supply 1.
All three phases of both power supplies are checked constantly on undervoltage, phase failure, phase balance and
correct rotation. In case of failure of supply 1 the unit is switched off. After a lapse of time which can be set at the
time relay (preadjusted: 10 seconds) power supply 2 is switched onto the unit. The unit starts by the automatic restart
which is integrated in the controller.
When the voltage of power supply returns, the unit is switched off again. On a second time relay a delay can be set
(preadjusted: 10 seconds), after which power supply 1 is switched onto the unit. The unit starts by the automatic restart.
12.5.1 Three Phase Control
The phase monitoring relay monitors a phase failure and a phase reversal. Excess voltage, undervoltage and the
phase imbalance are monitored in relation to the set values.
In case of a phase failure the phase monitoring relay is de-energized without delay and triggers an alarm. If the moni-
toring relay detects a wrong phase sequence during the A/C unit start, it is not energized and prevents the unit start.
You can adjust a triggering delay on the relay for the errors excess voltage, undervoltage and phase imbalance
(excess of the adjusted limit values).
Automatic restart
When the defective phase returns and if the voltage is within the limit values and the phase imbalance within the
adjusted tolerance, the A/C unit is restarted automatically.
Herefor the parameter "Phase restart" must be set to "1", either in the menu "Config/Values/Misc." of the C7000AT
or by the command "phase start 1".
Error
Adjustment
range
Factory setting for supply voltage
460V
400V
380V
230V
200V
Excess voltage
(upper limit value)
160 - 690V
490V
425V
404V
245V
212V
Undervoltage
(lower limit value)
160 - 690V
430V
375V
356V
215V
188V
Phase imbalance
off, 5 - 20%
5%
Triggering delay
0,1 - 20 s
3 s
