•
•
•
•
•
9.3.99 ALARM 427, FPC Supply
Cause
Supply voltage fault (5 V, 24 V, or 48 V) on fan power card is detected.
Troubleshooting
Check fan power card wiring.
Replace fan power card.
9.4 Troubleshooting
Table 95: Troubleshooting
Symptom
Possible cause
Test
Solution
Display dark/No
function
Missing input power.
Check for loose connections.
Check the input power source.
Missing or open fuses.
See
Open power fuses
in this table
for possible causes.
Follow the recommendations provi-
ded.
No power to the LCP.
Check the LCP cable for proper
connection or damage.
Replace the faulty LCP or connection
cable.
Short circuit on control volt-
age (terminal 12 or 50) or at
control terminals.
Check the 24 V control voltage sup-
ply for terminal 12/13 to 20–39, or
10 V supply for terminals 50–55.
Wire the terminals properly.
Incompatible 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.
–
To adjust the contrast, press [Status] +
[
▲
]/[
▼
].
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 supply (SMPS)
due to improper control wir-
ing or a fault within the AC
drive.
To rule out a problem in the control
wiring, disconnect all control wir-
ing by removing the terminal
blocks.
If the display stays lit, 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\No function
.
Motor not run-
ning
Service switch open or miss-
ing motor connection.
–
Connect the motor and check the serv-
ice switch.
No mains power with 24 V DC
option card.
–
Apply mains power.
LCP stop.
–
Depending on the operating mode,
press [Auto On] or [Hand On].
Missing start signal (Standby).
–
Apply a valid start signal.
Motor coast signal active
(Coasting).
–
Apply 24 V on terminal 27 or program
this terminal to
[0] No operation
.
Wrong reference signal
source.
Check reference signal:
Local
Remote or bus reference?
Preset reference active?
Program correct settings. Check
pa-
rameter 3-13 Reference Site
. Set preset
reference active in
parameter group
3-1* References
. Check for correct wir-
ing. Check scaling of terminals. Check
reference signal.
AQ357954340588en-000201 / 130R0881
138 | Danfoss A/S © 2020.09
Maintenance, Diagnostics, and
Troubleshooting
VLT® Refrigeration Drive FC 103
Operating Guide
