Static Power iSTS W - Output Settings

iSTS W
– User Manual
Page 24
6
.9 Output Settings
Output
steady state high value (%)
The
default value of 118%, can be changed from a nominal value from 105 to 135. This number will be set as
a
percentage
.
Averaging
time constant for this parameter is defined by “Steady-state failure time” typically 1.5 seconds.
Set
as a percentage from nominal – This parameter should always be wider than the S1 & S2 Steady state
high
threshold
. This will ensure that when there is a problem with S1/S2 the event list will report correctly. S
3
(Output)
sensing is provided as redundant sensing for online source S1 or S2 and in case of internal
thyristor
triggering
a fault.
When
the output reaches this value the alarm will be triggered and the STS will transfer to the alternative
source.
Output
steady state low value (%)
A
default value of 82%, can be changed from a nominal value of 70 to 95. This number will be set as
a
percentage
. Averaging time constant for this parameter is defined by “Steady-state failure time” typically 1.
5
seconds
. Set as a percentage from nominal – This parameter should always be wider than the S1 & S2
steady
state
low threshold. This will ensure that when there is a problem with S1/S2 event list will report correctly. S
3
(Output)
sensing is provided as redundant sensing for online source S1 or S2 and in case of internal
thyristor
triggering
a fault.
When
the output reaches this value the alarm will be triggered and the STS will transfer to the alternative
source.
Output
transient high value (%)
The
default value of 120%, can be changed from a nominal value of 105 to 135. This number will be set as
a
percentage
. The transient time constant for this parameter is defined by “Transient over-sampling time
constant
2
x 312 µsec”. Set as a percentage from nominal – This parameter should always be wider than the S1 & S
2
transient
high threshold. This will ensure that when there is a problem with S1 or S2 the event list will
report
correctly
. S3 (Output) sensing is provided as redundant sensing for online source S1 or S2 and in case of
internal
thyristor
triggering a fault. The operation is to transfer to the alternative source.
Transient
limits should be set outside Steady state limits.
Output
transient low value (%)
The
default value of 80%, can be changed from a nominal value of 70 to 95. This number will be set as
a
percentage
. The transient time constant for this parameter is defined by “Transient over-sampling time
constant
2
x 312 µsec” This parameter should always be wider than the S1 & S2 transient high threshold. This will
ensure
that
when there is a problem with S1 or S2 the event list will report correctly. S3 (Output) sensing is provided
as
redundant
sensing for online source S1 or S2 and in case of internal thyristor triggering a fault. The operation
is
to
transfer to the alternative source.
Transient
limits should be set outside steady state limits.
High
current time (minutes) at 110% & 125% Overload
The
default values for 110% (first column) is 60 minutes and for 125% (second column) is 20 minutes.
Exceeding
the
overload limits of 110% for greater than 60 minutes OR 125% for 20 Minutes will not affect the critical
load
and
no switching occurs. It is intended as a warning that the STS is overloaded. Failure to reduce the load
will
cause
semiconductor failures.
Consult
the manufacturer before setting to higher values to ensure that the unit will operate safely
without
failure
or overheating.
High
current time (secs) at 150% & 200% Overload
The
default values for 150% (first column) is 10 seconds and for 200% (second column) is 1 second. Exceeding
the
overload
limits of 150% for 10 seconds OR 200% for 1 second will not affect the critical load and no
switching
occurs
. It is intended as a warning that the STS is overloaded.
Failure
to reduce the load will cause semiconductor failures.
iSTS W