Dexter Laundry T900 Parts & Service Manual page 62

Fault Description
DRIVE VFD Over-current
OC Fault
DRIVE
VFD Over-voltage
OV Fault
62
Part # 8533-081-001 1/18
Customer Action
Condition This error is an over-current on the VF drive
Delay Delay time is 35 seconds
Action Stop the machine and clear the cycle. Keep
the door locked until the machine has stopped
moving and then unlock the door.
Solution Step 1: Check to make sure the washer cylinder
turns freely by hand. If it turns freely, continue
to step 2. If it does not, remove the belt and
see if the motor turns freely by hand. If the
motor turns freely, then check for obstructions
in the cylinder or check the bearings. If the
motor does not turn freely, replace the motor.
Step 2: Check the motor wires for a short
circuit between leads. If there are motor leads
that have conductors touching, separate them
and insulate them. If the wires are broken,
splice them together or replace the motor.
Step 3: Check braking resistors to see if they
measure the correct resistance. If a resistor
does not measure the proper value, replace it.
Condition This error is over-voltage on the VF drive
Delay Delay time is 35 seconds.
Action Stop the machine and clear the cycle. Keep
the door locked until the machine has stopped
moving and then unlock the door.
Solution "Step 1: Measure the supply voltage to the VFD
on the L1, L2 (or N), and L3 (if connected to
three phrase power). the supply voltage should
be from 187 to 264 VAC or 108 to 132 VAC
for a 120 VAC VFD. Also make sure the supply
wires on L1, L2 (or N) and L3 (if connected to
three phase power are securely connected.
Step 2: Check the braking resistor connections
at the VFD. The terminal screws should be
tight. Once of the braking resistor wires should
be connected to terminal B2.
Step 3: Measure each braking resistor
separately to make sure they are the correct
resistance. (200 for 1 and 2 Hp VFD and 160
for 3 Hp VFD).
Step 4: If you have a 240 VAC, high leg voltage
supply, try disconnecting the high leg. If this
cures the problem, either leave the high leg
disconnected, connect a transient voltage surge
suppressor (with some form of filtering) at the
voltage supply panel, connect a line choke on
the high leg or install a VFD filter.
"