Emerson E Series Installation Manual page 71

Watchdog Timer
The drive contains a watchdog timer to ensure that the firmware is operating
normally. I f the firmware fails to reset this timer every 10 milliseconds the
drive hardware will be reset, all inputs and outputs will be cleared (off), and
Watchdog Timer fault is generated.
Power Up Self-Test Failure
This fault indicates that the power up self-test has failed.
Non-volatile Memory Invalid
At power-up the drive tests the integrity of the non-volatile memory. This fault
is generated if the contents of the non-volatile memory are invalid.
Invalid Configuration
This fault code should not normally occur when using an MG series motor. I f
this fault occurs, please call Emerson Motion Control service for assistance.
Power Stage Fault
This fault is generated when a power stage over-temperature, over-current or
under voltage gate supply occurs. This can be the result of a motor short to
ground, a short in the motor windings, a motor cable short, or the failure of a
switching transistor.
High DC Bus Fault
This fault will occur whenever the voltage on the DC bus exceeds 440 VDC. The
most likely cause of this fault would be an open shunt fuse, a high AC line
condition, or an application that requires an external shunt (e.g., large load
and rapid deceleration).
Low DC Bus Fault
This fault will occur whenever the voltage on the DC bus drops below 96 volts.
The most likely cause of this fault is a reduction (or loss) of the AC power. A 50
ms debounce time exists with this fault to avoid faults caused by intermittent
power disruption.
Encoder State
Certain encoder states and state transitions are invalid and will cause the
drive to report an encoder state fault. This is usually the result of noisy encoder
feedback caused by poor shielding.
Troubleshooting
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