Generac Power Systems PowerManager 004975-2, Руководство пользователя

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NOTE:
Although this feature can be used on an individual generator at
any time, it is advised to only be performed with all the system
generators in this mode.
NOTE:
An MPS will perform better in backup mode with like-sized
generators than with unlike-sized generators.
n
DO NOT use this feature on a generator taken
out of service on the PM-SC. It will connect to
the Bus, but may not share power properly with
the other units that are still controlled by the
PM-SC.
3.11.7 AUTOMATIC BACKUP OPTION
The automatic backup option consists of the standard control sys-
tem with enhancements to automatically recover from most single
failures. This provides another level of redundancy to make the
system even more reliable. In addition to the PM-SC and PM-PC(s)
in the system, there is a controller to take over critical functions
if the PM-SC should no longer be able to control or monitor the
MPS. The manufacturer has developed the PM-PLS to be capable
of monitoring on-line generators and providing automatic permis-
sive and load shed functions similar to the PM-SC. The PM-PLS
shall be configured by the dealer’s trained MPS technician with the
same parameters configured in the PM-SC. Additional site wiring
is required to support this level of protection. Reference drawing
0F8112 that illustrates the required redundant wiring. Also, refer-
ence interconnect drawing 0F9326 for Gemini MPS or 0F9326A
for non-Gemini MPS.
3.11.8 AUTOMATIC BACKUP OPERATION
This mode of operation requires the addition of a PM-PLS if there
is an MPS failure. The automatic backup operation is available
with PM-PC and PM-SC firmware version 2.2H or later (Figure
3.20). The automatic backup operation consists of the normal
MPS operation with the added ability of each generator PM-PC to
decide when to synchronize and connect to the Bus if they are no
longer communicating with the PM-SC. If any of the generators are
operating in a backup mode, the entire system changes to backup
mode. When the MPS is in a backup mode, the communications
are no longer adequate to provide dynamic power sharing between
the connected generators while maintaining target frequency and
voltage. All the generators attempt to take their share of the load.
This results in the frequency varying by up to 3% and the volt-
age varying by up to 10% depending on the system load. Since
the PM-SC does not have complete knowledge of the system in
backup mode, it will not control the load shed signals and will only
partially control the permissive signals. The PM-PLS takes over
this operation when the system enters backup mode.
In addition to having the correct versions of firmware, the version
of GenLink must be 2.8.0 or later to allow enabling of automatic
backup feature.
Procedure for Enabling Automatic Backup Operation:
Using GenLink, connect to the PM-SC.
Open the “Configuration” pull down menu and select “Regulator
Settings” (Figure 3.21).
PM-SC
ATS
Pe
rmissiv
es
Load Sheds
Remote
Annunciator
Panel
Gen 1
PM-SC
Gen 2
PM-SC
Gen 10
PM-SC Gen 3
PM-SC
Gen 4
PM-SC
Gen 5
PM-SC
Gen 6
PM-SC
Gen 7
PM-SC
Gen 8
PM-SC
Gen 9
PM-SC
PM-PLS
Permissives
Load Sheds
2-wire Start
Gen Connected to Bus Under Backup Control
Gen #2 Connecting Signal
RS-485 Generator Communications Bus
Enable Backup Control
Figure 3.20 — MPS STANDARD CONTROL SYSTEM WITH AUTOMATIC BACKUP OPTION
Operation