InteliMains
NT
, SW version 3.2.0
InteliMains-NT-MCB-MGCB-3.2.0-Reference Guide.pdf,
©ComAp – April 2015
98
7.6.5
Control Groups
The physical group of the gen-sets (i.e. the site) can be separated into smaller logical groups, which
can work independently even if they are interconnected by the CAN2 bus. The logical groups are
intended to reflect the real topology of the site when the site is divided into smaller gen-set groups
separated from each other by bus-tie breakers. If the bus-tie breakers are closed the sub-groups have
to work as one large group and if the bus-tie breakers are open, the sub-groups have to work
independently.
The group which the particular controller belongs to is adjusted by the setpoint
Pwr management:
Control group
. If there is only one group in the site, adjust the setpoint to 1
(=COMMON).
The information which groups are currently linked together is being distributed via the CAN.
Each controller can provide information about one BTB breaker. The breaker position is
detected by the input
GroupLink
(i.e. this input is to be connected to the breaker feedback).
The two groups which are connected together by the BTB breaker mentioned above are
adjusted
by
setpoints
Pwr management:
GroupLinkLeft
and
Pwr management:
GroupLinkRight
.
N
OTE
:
The "group link" function is independent on the group, where the controller itself belongs to.
The controller can provide "group link" information about any two groups.
If the "group link" is opened the two groups act as two separated groups. If it is closed the
roups act as one large group.
The picture below shows an example of a site with 4 gen-sets separated by a BTB breaker into two
groups of 2. The BTB position is detected by the controllers 2 and 3. The reason, why there are 2
controllers used for detection of the BTB position, is to have a backup source of the group link
information if the primary source (controller) is switched off.
BTB
CAN
1
2
Controller
Controller
Control group:
2
GroupLinkLeft:
COMMON
GroupLinkRight: COMMON
BI Group link:
NC
Control group:
2
GroupLinkLeft:
2
GroupLinkRight: 3
Group link:
BTB feedb.
Control group:
3
GroupLinkLeft:
2
GroupLinkRight: 3
Group link:
BTB feedb.
Control group:
3
GroupLinkLeft:
COMMON
GroupLinkRight: COMMON
BI Group link:
NC
Controller
Controller
BI Goup
link
3
4
Figure:
Example of control groups
Once the BTB breaker is closed, the control group 2 and 3 become new group 2+3. The closed BTB
and the group link function influence the load reserve (i.e. increased by added gen-set of added gen-
sets). Load sharing applies for all gen-sets.
