ABB PS D75 840 Series Installation And Maintenance Instruction page 20

The motor does not start
Check the status on LED's and signal relays and read the explanation below.
See 6.1.1 for PS D without electronic overload protection and
See 6.2.1 for PS D(H) with electronic overload protection.
Status signals
I
No control voltage
• Check voltage on terminals 1 and 2.
• Correct voltage level according to the rating plate?
• Are the cooling fans running? (not PS DH30)
• If everything is OK - Internal fault on the PCB
II
No starting signal present
• Check the circuit for start signal.
a Connection between 7 and 10 present.
Start signal present, closed circuit between terminal 8 and 9
b PLC-connection
Connected +24 DC to terminal 9 and
-(OV) connected to terminal 10
VI (See also the fault codes and flow chart)
Alt. a)
Phase loss
• The main circuit contactor is not closing or closes to late. It must be closed within
100ms after start signal
• One or more phases missing due to tripped fuse
Alt. b)
High current switch off (The switch SC must have been in position Yes, otherwise no
tripping due to overcurrent)
• The main circuit contactor is not closing or closes to late. It must be closed within
100ms after start signal
• One or more phases missing due to tripped fuse
VII (See also the fault codes and flow chart)
Over temperature
• Check to make sure the cooling fans are working.
• Clean the heat sink if it is dirty
• Check the temperature monitor under the front cover.
Short circuit between terminals X3 1, 2.
If LED F2 is off, then change the temperature monitor.
VIII (See also the fault codes and flow chart)
Alt. a)
Shorted thyristor
• The motor can start with shorted thyristor when switch PF is in N (Off) position.
Then the status will be IX.
Change the faulty thyristor at the next maintenance shutdown.
Alt. b)
One of the thyristors is not working / Open circuit between motor and starter
Too small motor in the circuit ( too low current for the thyristors).
• Check the gate wiring under the front cover
• Change thyristor.
X (See also the fault codes and flow chart)
Tripped electronic overload ( only for PS D and PS DH with electronic over load )
• There is an overload ( too high load ) on the motor shaft.
• It can also be too long starting time.
Check if the current limit is set to a low value.
If the value is set too low there is not enough torque for the start.
PS: It's not possible to reset the over load if the start signal is present.
- 20 -