7.4.5 Load-dependent stop flowchart
PMS control,
GENSET in
AUTO
Available
power > Load-
dependent
stop limit
No
Yes
Stop last
genset in
priority queue
Load-dependent
stop timer starts
Timer run out
No
Yes
Yes
No
Available
power > Load-
dependent
stop limit
1. The load-dependent stop timer starts when the PMS available power is more than
(the load-dependent stop limit + the nominal power of the lowest priority running
genset).
2. If the PMS available power is more than (the load-dependent stop limit + the
nominal genset power) until the timer runs out, the power management system
sends a stop command to the last running genset in the priority order.
7.4.6 Power method for load-dependent start and stop
For the
Power
method, the power management system (PMS) starts or stops gensets with GENSET controllers in AUTO mode,
based on the section's PMS available power.
The
Power
method may be based on active power (P, in kW) (
Calculation in P
) or apparent power (S, in kVA) (
Calculation in S
). The
available power genset start and stop function calculations are the same for apparent power as they are for active power.
INFO
Calculation in S
is typically selected if the connected load is inductive and the power factor is below 0.7.
The following example shows how the parameters interact with the PMS nominal power, connected consumed power and PMS
available power.
Load-dependent start
If the PMS available power is less than the
Load-dependent start
limit for the specified time, then the first genset that is ready to
start (in the priority order) is started and connected.
DESIGNER'S HANDBOOK 4189340911K UK
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