Operation
116
5.14 Functional Summaries (continued)
5.14.2 Low Current Protection
A Low Current trip occurs when the current output measured by the unit falls below the level
specified by the Low amps level parameter for a length of time specified by the Low Amps Time
parameter
1
. I LOW = Low Amps Level.
2
. If I LOAD drops below
‘Low Amps Level’ and ‘Low
Current’ is set to ‘on’, and
‘Low Amps Time’ is set to
minimum then the unit will
trip as indicated by the short
thick dotted line.
3
. If ‘Low Amps Time’ is set
to maximum and I LOAD
rises above ‘Low Amps
Level’ before ‘Low Amps
Time’ has elapsed then the
unit will not trip.
5.14.3 Current Limit
1
. If I
LOAD
exceeds ‘Current Limit
Level’ for time ‘Limit Time Out’ and
‘C/L Time Out’ is on, the unit will trip
at the thick dotted line. If ‘C/L Time
Out’ is off the unit will continue
ramping until T.O.R. and then enter
the Dwell period.
2
. If the unit current limits during
start-up the start time will be
elongated by the amount of time that
the unit was current limiting.
3
. The actual current rises slightly
above the level set in ‘Current Limit’
because the unit manages the
current through control of the
thyristor firing delay angle.
