Service manual

4.5 Fault Symptoms
4.5.1 No Display
The LCP display provides two display indications. One with
the backlit LCD alphanumeric display. The other is three
LED indicator lights near the bottom of the LCP. If the
green power on LED is illuminated but the backlit display
is dark, it indicates that the LCP is defective and must be
replaced.
On
Warn.
Alarm
130BP044.10
Illustration 4.1
Be certain, however, that the display is dark. Having a
single character in the upper corner of the LCP or just a
dot indicates that communications may have failed with
the control card. This situation typically appears when a
serial bus communication option has been installed in the
frequency converter and is either not connected properly
or is malfunctioning.
If neither indication is available, then the source of the
problem is elsewhere. Proceed to 6.4.1 No Display Test
(Display is Optional) to carry out further troubleshooting
steps.
4.5.2
Intermittent Display
Cutting out or flashing of the entire display and power
LED indicates that the power supply (SMPS) is shutting
down as a result of being overloaded. The overload may
be due to improper control wiring or a fault within the
frequency converter itself.
The first step is to rule out a problem in the control wiring.
To do so, disconnect all control wiring by unplugging the
control terminal blocks from the control card.
If the display stays lit, the problem is in the control wiring
(external to the frequency converter). Check all control
wiring for shorts or incorrect connections.
If the display continues to cut out, follow the procedure
for 4.5.1 No Display as though the display was not lit at all.
4.5.3
Display (Line2) Flashing
This indicates that a local stop command has been given
by pressing the stop key on the front of the LCP. The
frequency converter cannot accept any further run
command until the local stop is cleared. Press [Start] to
clear the local stop.
CAUTION
The frequency converter may start immediately. If the
frequency converter is being operated in local control, or
remote control with a maintained run signal, the frequency
converter starts immediately.
4.5.4 WRONG or WRONG LCP Displayed
If the message WRONG or WRONG LCP appears, it is due
to a faulty LCP or the use of an incorrect LCP.
Replace the LCP with a correct and functioning one.
NOTE
Error 84 appears if the LCP cannot communicate with
FC 101.
4.5.5 Motor Will Not Run
If this symptom is detected, verify that the unit is properly
powered up (display is lit) and that there are no warning
or alarm messages displayed. The most common cause of
this problem is either incorrect control logic or an
incorrectly programmed frequency converter. Such
occurrences result in one or more of the following status
messages being displayed.
LCP Stop
[Off] has been pressed. Line 2 of the display also flashes
when this situation occurs.
Press [Auto On] or [Hand On]. Refer to the Input Terminal
Signal Test.
Standby
This message indicates that there is no start signal at
terminal 18.
Ensure that a start command is present at terminal 18.
Refer to the Input Terminal Signal Test.
Unit ready
Terminal 27 is low (no signal).
Ensure that terminal 27 is logic “1”. Refer to the Input
Terminal Signal Test.
Run OK, 0 Hz
This message indicates that a run command has been
given to the frequency converter but the reference (speed
command) is zero or missing.
Troubleshooting
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