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11 Fault diagnosis and troubleshooting
11.1 General fault diagnosis and troubleshooting
Fault
Cause
Remedy
Device cannot be
switched on
No mains voltage
Device fault
•
•
Connect the device to the
mains.
Send the device to the manu-
facturer for inspection.
Stop using the device!
Charging process
takes longer than
usual
Derating active due
to high ambient
temperatures or poor
circulation
Parallel loads
•
•
Ensure sufficient circulation
at the rear of the device, and,
if necessary, remove any dust
by vacuuming.
Remove parallel loads
11.2 Fault diagnosis STM 820/860
Fault
Cause
Remedy
LED permanently
red
No battery connected
Totally discharged
battery connected
(voltage < V)
Battery connected
with reverse polarity
•
•
•
Connect the battery.
Disconnect the battery and
check polarity.
LED slowly flashes
red
Battery fault
Max. battery capacity
has been reached
Battery with too high
or too low a voltage
is connected
Overvoltage due to
additional power
supply/
charger
•
•
•
•
Check the battery.
Set the capacity correctly.
Check the battery. Disconnect
other loads.
Disconnect the battery. The
battery charger is not suitable
for this battery.
Disconnect the additional
power supply/charger.
LED quickly
flashes red
Device fault
•
Send the device to the manu-
facturer for inspection.
Stop using the device!
11.3 Fault diagnosis STM 821/861
STM 81/861 devices display fault messages in plain text.
During charging, an info screen which displays additional device data (e.g. tem-
peratures) can be opened with the down (more) button.
Fault message
Cause
Remedy
Device fault
Hardware defective
•
Send the device to the manu-
facturer for inspection.
Stop using the device!
Overvoltage
Wrong battery con-
nected
Additional power
supply/charger con-
nected
•
•
Disconnect the battery. The
battery charger is not suitable
for this battery (battery volt-
age too high).
Disconnect the additional
power supply/charger.
Battery fault
Maximum capacity
charged
•
Correct the battery capacity
setting.
Check the battery.
Disconnect other loads.