Convection Circuit

8-10

Delta Blower Motor Controller Fault Codes & Troubleshooting

Fault

Name

Fault Descriptions Corrective Actions

Oc The AC drive detects an
abnormal increase in
current.
1. Check whether the motors horsepower corresponds to
the AC drive output power.
2. Check the wiring connections between the AC drive
and motor for possible short circuits.
3. Increase the Acceleration time (Pr.1-09, Pr.1-11).
4. Check for possible excessive loading conditions at the
motor.
5. If there are any abnormal conditions when operating
the AC drive after short-circuit being removed, it should
be sent back to manufacturer.
Ou The AC drive detects that
the DC bus voltage has
exceeded its maximum
allowable value.
1. Check whether the input voltage falls within the rated
AC drive input voltage.
2. Check for possible voltage transients.
3. Bus over-voltage may also be caused by motor
regeneration. Either increase the decel time or add an
optional braking resistor.
4. Check whether the required braking power is within the
specified limits.
OH The AC drive temperature
sensor detects excessive
heat.
1. Ensure that the ambient temperature falls within the
specified temperature range.
2. Make sure that the ventilation holes are not obstructed.
3. Remove any foreign objects on the heatsinks and
check for possible dirty heat sink fins.
4. Provide enough spacing for adequate ventilation.
Lu The AC drive detects that the DC bus voltage
has fallen below its minimum value 1. Check whether the input voltage falls within the rated AC
drive's input voltage.
OL The AC drive detects excessive drive output
current.
Note: The AC drive can withstand up to 150% of
the rated current for a maximum of 60 seconds.
1. Check the motor overload (shaft binding).
2. Reduce torque compensation setting as set in Pr.7-02.
3. Increase the AC drive's output capacity.
oLI Internal electronic overload trip 1. Check for possible motor overload.
2. Check electronic thermal overload setting.
3. Increase motor capacity.
4. Reduce the current level so that the drive output current
does not exceed the value set by the Motor Rated current
Pr. 7-00
oL2 Motor Overload. Check the parameters settings
(Pr.6-03 to Pr. 6-05) 1. Reduce the motor load.
2. Adjust the over-torque detection setting to an appropriate
setting.