Rockwell Automation 825 Smart Motor Manager User Manual - Manual (Page 138)

8-6 Error Diagnosis and Troubleshooting
Publication 825-UM001B-EN-P January 2001
Table 8.A Possible Causes and Actions (Continued)
LCD Designation Possible Causes Actions
Earth (ground)
fault
(Holmgreen/
residual) trip
Earth (ground) fault motor
winding or cable
Repair damage.
Trip when running:
• Primary current transformer
wrongly wired
• Primary current transformer
saturated
• High proportion of third
harmonic in star-delta
• Correct wiring.
• Raise pickup threshold.
• Raise pickup threshold to 50%
or more.
Earth (ground)
fault warning
with core
balance
transformer
Earth (ground)
fault trip
with core
balance
transformer
Trip during start: Primary and
core balance transformer wired
incorrectly Correct the wiring (core balance
transformer may only surround
the three motor leads).
Long motor cable Raise pickup threshold.
Earth (ground) fault in motor
winding or cable due to:
•
Moisture
• Dirt
•
Mechanical damage
Eliminate cause.
Short-circuit
trip
Short-circuit or earth (ground)
fault in motor winding or cable
Repair damage.
Trip when motor is switched on,
due to inrush current
Increase trip delay to > 0.1 s.
Pickup threshold is < ,
A
Set pickup threshold to > ,
A
.
Underload
warning
Underload trip
Underwater pump running dry
Eliminate cause, lower pickup
threshold if necessary or increase
trip delay.
Faulty fan blades
If tripping takes place too soon
after starting, increase the start
delay.
Torn conveyor belt
Eliminate cause. Broken transmission elements
Pumping against a closed valve
Current setting
,
e
too high Set correct value.
Max. number
of starts/h
reached
Maximum number of starts has
been exceeded.
Wait until another start is
permissible. Release will be
automatic.
If another start is permissible,
increase number of start/hour by
“1” and start again.
Start in max.
starting time
not possible
Overloaded
Reduce load or raise max. starting
time to permissible value.
Transport material jammed Eliminate cause.
Viscous material
Raise max. starting time to
permissible value.
EF HOLMG TRIP
EF C WARNING
EF CORE TRIP
SHORT CIRC PROT
UL WARNING
UNDERLOAD TRIP
START INHIB TRIP
START CONT TRIP