Parameter
Range
Default
Notes
If
Calculation in S
is selected, this limit is based on the percentage of apparent
power.
Delay
5 s to 1 h
30 s
If the load exceeds the limit for the whole of the delay period, then the PMS starts
the next genset in the priority order.
Configure the parameters under
Configure > Parameters > Power management rules > Configuration # > Load-dependent
start/stop > Start 2
(where # is 1 to 8) to define the second set of start parameters. By default, the PMS ignores these parameters.
Parameter
Range
Default
Notes
Enable
Not enabled,
Enabled
Not
enabled
Not enabled
: The PMS ignores this set of parameters.
Enabled
: The PMS uses this set of parameters for load-dependent start. The
Start 1
parameters can also be active. The controller starts an additional genset if
this is required by either set of parameters.
P available
limit
1 MW to 9 GW 100 kW
Calculation in P
and
Method
=
Power
must be selected, otherwise this parameter
is ignored.
If this amount of PMS power is not available for the delay period, then the PMS
starts another genset, according to the priority order.
S available
limit
1 kVA to 9 GVA 100 kVA
Calculation in S
and
Method
=
Power
must be selected, otherwise this parameter
is ignored.
If this amount of PMS apparent power is not available for the delay period, the
PMS starts another genset, according to the priority order.
Load limit
1 to 100 %
90 %
Method
=
Percent
must be selected, otherwise this parameter is ignored.
The load percentage is the total power consumed, as a percentage of the PMS
nominal power. If the load percentage exceeds this parameter for the
Delay
period, then the PMS automatically starts and connects another genset.
If
Calculation in P
is selected, then this limit is based on the percentage of active
power.
If
Calculation in S
is selected, then this limit is based on the percentage of
apparent power.
Delay
5 s to 1 h
30 s
If the load exceeds the limit for the whole of the delay period, the PMS starts
another genset, according to the priority order.
Example
Start load limit example
The system consists of three gensets. Genset A has a nominal power of 1000 kW. Gensets B and C each have a nominal
power of 500 kW. The total power consumed in the system (that is, the load) is 900 kW. The
Power selection
is
Calculation
in P
. The
Method
is
Percent
. The
Load limit
is 90 %.
Example 1
: Gensets A and B are running. The total nominal power connected is Genset A nominal power + Genset B
nominal power = 1500 kW.
The load percentage is 900 kW / 1500 kW = 0.6 = 60 %. The PMS does not start another genset.
Example 2
: Only Gensets B and C are running. The total power connected is 1000 kW. The load percentage is 900 kW /
1000 kW = 0.9 = 90 %. If the load percentage remains at 90 % (or more) for the
Delay
time, the PMS starts another
genset.
DESIGNER'S HANDBOOK 4189340911K UK
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