Manual genset priority inputs also change the dynamic genset priority.
There are no parameters specific to
Dynamic
priority.
Rules for dynamic genset priority selection
•
Each genset's priority is according to the order in which it connects to the busbar. This applies to both AUTO and SEMI mode.
The first genset to connect gets priority 1, the second genset gets priority 2, and so on.
◦
The controller also monitors the order in which the gensets connect during blackout recovery.
•
If the operator puts a GENSET controller in SEMI mode and opens the breaker, then that genset gets the lowest priority.
•
If a genset breaker trips, then that genset gets the lowest priority. The gensets in the priority order behind that genset each move
up one place.
•
The dynamic genset priority also changes in response to inputs from the 1st priority button on the GENSET controller display
units, as well as inputs from
Power management > 1st priority
digital inputs, and the
Configure > Priority
interface on the
display unit.
Dynamic genset priority example
The system consists of four gensets and the load requires one genset.
1. Genset A is running, and the priority order is A, B, C, D.
2. Genset A's breaker trips and there is a blackout.
3. The power management system moves Genset A to the back of the priority order (because its breaker tripped). The
new priority order is B, C, D, A.
4. The blackout recovery sequence sends commands to the first two gensets in the priority order to start (B and C).
Genset C starts and connects to the busbar first. Genset B does not start. The blackout recovery sequence therefore
starts and connects genset D.
5. The new priority order is C, D, A, B. This is because genset C connected first, and genset B did not start.
7.3.5 Running hours for genset priority
You can use
Running hours
for genset priority to ensure that all the gensets have about the same running hours (total or offset). This
method checks the running hours at regular intervals. It places the gensets with the lowest running hours at the front of the priority
order, while the gensets with the highest running hours are at the back of the priority order. If the genset priorities are different from
the running gensets, the genset(s) with the lowest number of running hours is started, and the genset(s) with the highest number of
running hours is stopped.
INFO
If two (or more) gensets have exactly the same number of running hours, the genset priority is decided using the controller
Controller ID
numbers. The controller with the lowest
Controller ID
has the first priority.
Parameters
Configure these parameters under
Configure > Parameters > System power management > Priority > Running hours
.
Parameter Range
Default Notes
Method
Total, Trip
Total
Total
: The priority is based on the total running hours for each genset.
Trip
: The priority is based on the running hours for each genset since the timer was last reset
(similar to a trip meter in a car).
Swap timer 1 to 20000 h 175 h
The regular interval for re-evaluating the genset priority, based on running hours.
Total
By default, the priority order calculation is based on each genset's absolute running hours.
DESIGNER'S HANDBOOK 4189340911K UK
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