9 Basic Troubleshooting
9.1 Start Up and Operation
Symptom
Possible cause
Test
Solution
Display dark/No function
Missing input power.
See
.
Check the input power source.
Missing or open fuses or circuit
breaker tripped.
See open fuses and tripped circuit
breaker in this table for possible
causes.
Follow the recommendations
provided.
No power to the LCP.
Check the LCP cable for proper
connection or damage.
Replace the faulty LCP or
connection cable.
Shortcut on control voltage
(terminal 12 or 50) or at control
terminals.
Check the 24 V control voltage
supply for terminals 12/13 to 20-39
or 10 V supply for terminals 50 to
55.
Wire the terminals properly.
Wrong LCP (LCP from VLT
®
2800
or 5000/6000/8000/ FCD or FCM).
Use only LCP 101 (P/N 130B1124)
or LCP 102 (P/N 130B1107).
Wrong contrast setting.
Press [Status] + [
▲
]/[
▼
] to adjust
the contrast.
Display (LCP) is defective.
Test using a different LCP.
Replace the faulty LCP or
connection cable.
Internal voltage supply fault or
SMPS is defective.
Contact supplier.
Intermittent display
Overloaded power supply (SMPS)
due to improper control wiring or
a fault within the adjustable
frequency drive.
To rule out a problem in the
control wiring, disconnect all
control wiring by removing the
terminal blocks.
If the display stays lit, then the
problem is in the control wiring.
Check the wiring for shorts or
incorrect connections. If the display
continues to cut out, follow the
procedure for display dark.
Basic Troubleshooting
VLT
®
HVAC Drive D-Frame
Instruction Manual
MG16D222 - VLT
®
is a registered Danfoss trademark
9-1
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