Atlas Copco QAS 250-330 JD T4i, Инструкция по эксплуатации

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needs to be programmed in the application that is required
(AMF, LTO, FP, MPE) and AUTO mode.
Installations are possible with stand-alone generators or
with the Mains (extra Qc4002™ Mains is then needed). A
number of Qc4002™ units are being used in the power
management application, i.e. one for each mains breaker
(Qc4002™ mains controller), if installed, and one for each
generator (Qc4002™ genset controller). All units
communicate by means of an internal CANbus
connection.
In an application with PMS it is important to program
correctly the Start & Stop signals between the different
generators because of the following reasons:
– The maximum load step needs to be programmed in the
Qc4002™ controllers. This never may exceeds the power
reserve of the running generators. Otherwise the gensets
will go in overload with a sudden max. load increase
before the next generator is started up and connected to the
busbar.
– To prevent the gensets to run in a start - stop loop.
The start signal is the value of the maximum required load
step.
The stop signal is the value when the generator should be
stopped automatically.
Example: Installation with 3 gensets
G1 = 300 kW; G2 = 200 kW; G3 = 200 kW.
– Start signal is set at 90 kW (maximum load step < 90 kW).
Start signal if:
Total Power needed > (total available power of running
gensets -set point start signal).
• Only G1 is running; at 210 kW load (300 kW - 90 kW) =>
G2 will be started.
• G1 & G2 are running; at 410 kW load (200 kW + 300 kW
- 90 kW) => G3 will be started.
– Stop signal is set at 100 kW and priority is set as (high) G1
> G2 > G3 (low).
Stop signal if:
Total Power needed < (Total available power of running
gensets - Power of generator with lowest priority - set point
stop signal).
• G1 & G2 & G3 are running; at 400 kW (700 kW - 200 kW
- 100 kW) => G3 will be stopped.
• G1 & G2 are running; at 200 kW (500 kW - 200 kW - 100
kW) => G2 will be stopped.
The priority on starting & stopping the generators can be
chosen on priority settings or on the amount of running
hours. In manual mode the start & stop sequence is
determent by the chosen priority between the generators.
The generator with the lowest priority will start as the
latest genset and will stop as first. If running hours are
chosen as priority the start & stop sequence will be defined
based on the actual running hours of the different
generators. The lowest running hours will get the highest
priority.
Paralleling
Prior to starting parallel operation of two generators,
following connections need to be made:
– Connect the communication cable between the generators
(sockets X30 & X31).
Each dedicated generator or SAPE has two of these
connections, to enable paralleling more than two generators.
– Connect the load with the generator.
Go via the site distribution panel (to be installed by the
customer) to connect the generator(s) and/or the SAPE unit(s)
with the load. Always connect generator with the load, and
never directly with second generator.
By programming the parameters in
AUTO mode, the generator can start up
immediately. It is recommended to place
the generator in SEMI-AUTO mode
while programming all the PMS
parameters !
When paralleling generators with PMS,
it is no longer necessary to use the
analogue load sharing lines. This will be
done through the PMS communication
lines. Use a screened CAN
communication cable with a maximum
total distance of 200 meters. Do not
connect the cable screen to the ground!
Use a 120 Ohm resistor at both end
controllers of the PMS.
For more information on this option,
see User Manual Qc4002™.
When paralleling, make sure to disable
the Earth leakage relay by putting
switch S13 into off position.
QAS 1 QAS 2
Site distribution
panel
Load
CORRECT
QAS 1 QAS 2
Load
WRONG