7.7.4 Heavy consumer flowcharts and example
Heavy consumer request flowchart
Heavy
consumer
request on
Enough
power
No
Yes
Start genset
Start reservation
timer
Timer
expired
No
Yes
Alarm
HC
request
(continuous)
on
No
Yes
Activate heavy
consumer
acknowledge
Sequence ends
1. When a heavy consumer needs to start, a request is sent to the controller
by activating the
Heavy consumers > [Heavy consumer #] > Request
digital input.
2. The PMS starts the
Heavy consumer reservation not possible
timer.
3. The PMS uses the heavy consumer
Initial load
to calculate whether there
is enough power for the heavy consumer to connect.
4. The PMS starts additional genset(s) if needed (that is, if the PMS available
power after the heavy consumer connects is less than the load-dependent
start limit).
•
If power reservation is impossible, or if the
Heavy consumer
reservation not possible
timer runs out, then the controller activates the
Heavy consumer reservation not possible
alarm.
INFO
If you use a pulse request signal, then the heavy consumer request
sequence can only stop when there wasn't enough power for the
heavy consumer to connect and the
Heavy consumer reservation
not possible
timer runs out. If you use a continuous signal, then the
heavy consumer request sequence can be stopped at any time.
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