UPS MKD2000/3000 XL
Manual
MKD XL Series
Page 35 of 45
11 Troubleshooting
Just authorized persons are allowed to do troubleshooting at the UPS.
If failures occur during UPS service, try to solve the problem by following the
below mentioned schedule:
Problem
Possible reason
solution
No function,
no display,
no warning message.
The UPS has got no power
supply or is not switched-on.
Assure that all connections are
correct and confirm this by
corresponding voltage
measurements. Switch the fuse of
the UPS on.
The UPS cannot be started,
no warning message.
The ON buttons have not
been pushed long enough.
Push the ON buttons for about 2-
3sec.
The UPS is in bypass mode.
The “fault” LED is glowing,
the display shows “Overload
fault”, acoustic alert sounds
The UPS is overloaded with
regard to the connected
machines
Disconnect the connected
machines or a part of it from the
UPS until the load display
indicates <= 100 %.
The UPS is in bypass mode.
The fault LED is glowing; the
display shows “Temp. fault”,
acoustic alert sounds
The internal temperature of
the UPS is too high
Switch off the UPS, disconnect
the connected machines and call
the customer service
The UPS is in bypass mode.
The fault LED is glowing; the
display shows “Inverter
fault”, acoustic alert sounds
The inverter of the UPS is
not operational
Switch off the UPS, disconnect
the connected machines and call
the customer service
The UPS is in bypass mode.
The fault LED is glowing; the
display shows “DC_BUS
fault”, acoustic alert sounds
The DC bus of the UPS is
not operational
Switch off the UPS, disconnect
the connected machines and call
the customer service
