Overload; System Crash During Startup; Hardware Limit Fault - Siemens SINUMERIK 808D Service Manual

3.13

Overload

Fault description
The axis cannot move or moves difficultly because of overload (the drive may issue an overload alarm).
Diagnostic steps
1. Check whether the guide lubrication is sufficient:
Whether the lubricating pipe/nozzle is blocked
•
Whether the lubrication interval time is set properly (the interval should not be too long)
•
2. Stop the machine and check whether the guides/screws are blocked by the machining waste. If so, it may need prop-
er cleaning.
3. Check whether the connection of the shaft coupling is smooth and concentric.
3.14

System crash during startup

Fault description
The system loading process crashes during startup (usually the HMI freezes when it loads to 40%).
Diagnostic steps
1. Power off and restart the control system. Check whether the fault is resolved.
2. Power off the control system and check whether the CF card is insert-
ed correctly or has a faulty contact, and then power on again to check
whether the fault is resolved.
3. Replacement and maintenance are necessary if the fault still exists after the above inspection, because probably the
PPU is damaged.
3.15

Hardware limit fault

Fault description
Case 1: The hardware limit switch alarm appears on the PPU.
Case 2: The axis has crossed the hardware limit, but can still move without any alarm.
Diagnostic steps
Case 1
1. Press and hold down the following key on the PPU while pressing the axis traversing key at the same time to make
the feed axis move in the opposite direction. The alarm can then be cleared when the axis moves away from the
hardware limit switch.
2. Check the hardware limit switches on the machine if the fault still exists:
Check whether the hardware limit switch connection is good with a multimeter.
•
Check whether the hardware limit switches are damaged.
•
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Service Manual
01/2017