ABB ACS880 - Underload Ride through Recovery Sequence

Underload warning
Warning + Shutdown
Delay
time
Delay
time
Load signal / Limit
Reference
Underload delay
Underload act
Underload recovery active
Warning
Fault
Shutdown
Delay
time
Fault
Underload boost active
Underload drop active
The diagram below illustrates various overload protection scenarios and possible
responses.
Overload warning
Warning + Shutdown
Fault
Delay
time
Delay
time
Delay
time
Load signal / Limit
Reference
Overload delay
Overload act
Overload safe speed active
Warning
Fault
Shutdown
￭
Underload ride through recovery sequence
The Underload protection function protects the motor casing in the presence of
fluid flowing over the motor cases. When an ESP is pumping the fluid (oil), gas
might be ingested by the ESP. This results in a reduction or removal of a fluid
flowing over the motor casing which results in overheating of the motor. The
presence of gas can be inferred by the detection of an underload condition.
ESP program features 57