23
Carlo Gavazzi LTD
RSWT
RSWT DS ENG
17/05/2018
Number of flashes
5
Alarm
Locked rotor
Alarm description
If a current ≥ 8xFLC setting for 100 msec is detected, the RSWT will issue the
locked rotor alarm.
Alarm recovery period
5 minutes
(If manual reset mode is applied, alarm can be reset by pressing the Test/
Reset button).
Consecutive alarms for hard reset
4
Action to recover alarm
The alarm will self-recover (in Auto-recovery mode) after 5 minutes.
Troubleshooting
•
Check that FLC setting is not smaller than motor name plate current.
•
Check that the RSWT model is suitably rated for the motor.
•
Check motor windings resistance to check if motor is damaged.
Number of flashes
7
Alarm
Over-temperature
Alarm description
The RSWT constantly measures the heatsink and thyristors (SCRs) tempera-
ture. If the maximum internal temperature is exceeded (for a minimum of 0.5
sec) an over-temperature alarm is triggered. This condition can be triggered
by too many starts per hour, an over-load condition during starting and/or
stopping or a high surrounding temperature.
Alarm recovery period
Depends on the cooling period.
(If MANUAL reset mode is applied, alarm can be reset by pressing the Test/
Reset button).
The RSWT will only recover if the internal temperature is within safe limits.
Consecutive alarms for hard reset
4
Action to recover alarm
The alarm will self-recover (in Auto-recovery mode) - the recovery period will
depend on the cooling time required by RSWT. The higher the surrounding
temperature, the longer the cooling period.
Troubleshooting
•
Check that the specified number of starts/hr are not exceeded.
•
Check that the surrounding temperature around the soft starter is within
limits.
Number of flashes
8
Alarm
Overload
Alarm description
The overload alarm can be triggered in case of the following conditions:
Measured current > 1.05 x FLC during transition from ramp-up to bypass.
High resistance (> 1000 ohm) at P1, P2 terminals.
Load current > FLC. Trip time will vary according to Trip Class 10.
Alarm recovery period
Depends on the cooling period.
(If manual reset mode is applied, alarm can be reset by pressing the Test/
Reset button).
The RSWT will only recover if the internal temperature is within safe limits.
Consecutive alarms for hard reset
4
Action to recover alarm
The alarm will recover automatically after 5 minutes. If manual reset mode is
enabled, press Test/Reset button.
Note: allow enough time for the motor to cool before attempting the next start.
Troubleshooting
•
Check that the P1, P2 terminals are shorted (unless PTC is used).
•
Make sure that the FLC setting is according to the current on the motor
name plate.
•
Check for any blockages in the load.
•
If overload alarm occurs during ramp-up try to set a shorter ramp-up time or
increase the FLC setting.
