R&M Materials Handling VARIABLE SPEED CONTROLS ControlMaster NXT Service Manual User Manual
Page 48
R&M Materials Handling, Inc.
4501 Gateway Boulevard
Springfield, Ohio 45502
P.: (937) 328-5100
FAX: (937) 325-5319
48/53
R&M Materials Handling, Inc. reserves the right to alter or amend the above information without notice.
X
Blink
Seven
times
7
X
OFF
Other fault
Note: There is a pause after each time the green LED has finished blinking the error code sequence. After the pause, the
green LED starts blinking again.
The warning and fault code numbers and corresponding warnings and faults, possible causes and suggested
solutions are listed in the following table.
Code
Warning or Fault
Possible cause
Solution
1
Over current / current
limit (stall)
• A sudden and significant load increase
has occurred
• There is a short circuit in the motor cable
• The motor is inadequate for the
application
• The motor parameters have been set
wrong
• Current limit activates
• Ramp time is too short
• Check the load of the motor
• Check the motor brake operation
• Check the connection of the motor cable
• Check the motor insulation
• Verify the correct parameters
• Check crane/trolley runway clearness
To reset: Power off and restart after 1 min.
2
Power supply under- or
over voltage, over
voltage at start
• The supply voltage is below 240VAC
• The supply voltage is unbalanced
• The deceleration time is too short
• The supply voltage is over 528 VAC
(480V+10%), has over voltage spikes or
not sinusoidal wave form
• Check that the supply voltage is not
unbalanced
• Check that the supply voltage level is
above 380VAC-15%. Use, for example,
autotransformer to boost the voltage
• Set a longer deceleration time
• Measure the supply voltage level and
wave form, use an autotransformer to
lower the voltage
• Check the braking resistor cable (model
006, not 003)
• Check the braking resistor type and
resistance (internal 120
Ω
, external 90
Ω
)
To reset: voltage must increase above the
limit OR power off and restart after 1 min.
Main voltage must be under 528 V
AC
3
Frequency converter
Under / over temperature
• The crane is operated in a temperature
that is too low/high
• The cubicle/panel heating is not working
• The cubicle/panel isolation is broken or
the door is open
• The cubicle/panel cooling is not working
• Dust inside the frequency converter
• Broken cooling fan
• Check that the environment temperature
meets the crane’s requirements
• Check the cubicle/panel heating/cooling
systems and air flow. If cooling fan is not
working replace the frequency converter.
To reset: when the ambient temperature
rises above -10˚C OR drops below +40˚C.
4
Earth fault in motor
output
• The motor load is not symmetric
• There is an insulation failure in the motor
winding or motor cable
• Check the motor/motor cable insulation
(phase-ground, phase-phase)
To reset: power off and restart after 1 min
5
External stop / limit
warning
• Limit switch is activated
• The motor has overheated
• Loose or missing wire in DI6
• Parameter S5 setting
• Drive back from limit switch
• Wait until the motor is cooled down
To reset: Power off and restart after 1 min.
6
DC bus over voltage
• DC bus voltage has been too high
because of too short slowdown ramp time
• The tailwind load is too high or, in tandem
use, the other crane is pushing
• Check the braking resistor connection
• Increase the deceleration ramp time
(Switch group S3)
To reset: leave the controls at a neutral
position at least 0.5 second