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Appendix C: BACnet integration
PRC-E Series Instruction Manual
MN014003EN August 2015 www.eaton.com
Step 3 .
This opens the “BACnet Configuration” page.
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The “Instance” is a unique identifier for the PRC-E
controller on the BACnet system
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The “Network” is a routing setting that signifies what part
of the system this PRC-E controller will be associated
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The “Port” is the communication port setting. This is used
for the BACnet communications from the PRC-E controller
Priority levels are set to achieve certain level of command
importance in the BACnet system operation. A smaller
number indicates a higher priority level.
In the PRC-E controller:
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The “External”—Network Level Priority (default is 13)
indicates override (out-of-service) setting
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The “Internal”—Controller Level Priority (default 15)
indicates normal (in-service) setting
To edit the BACnet/IP attributes,
Step 4 .
Click the corresponding entry fields and input the
required data for each.
Step 5 .
Click the “Save Changes” button to save edits.
Many BACnet/IP clients can automatically discover devices,
objects and properties within the panelboard. The most
commonly used BACnet objects in the Pow-R-Command
PRC-E panelboard are binary outputs and binary values,
although there are many other types of objects supported.
Physical controllable circuit breakers connected to BCBs
are represented as BACnet Binary Output objects with
instance numbers of 101 through 842. The instance number
is the panelboard number multiplied by 100, added to the
controllable circuit breaker number within the panelboard.
For example, the first circuit breaker in the first panelboard
will be binary output 101. The 42nd controllable circuit
breaker in the first panelboard will be binary output 142. The
second controllable circuit breaker in the third panelboard
will be binary output 302, and so on.
The commanded state of the controllable circuit breaker is
reflected in the BACnet Present Value property (property
85) and feedback actual status is reflected in the Feedback
Value property (property 40). Writing to the Binary Output
object turns individual circuit breakers ON and OFF; if the
priority level assigned to the command is above 15, it will
put them out-of-service. Relinquishing all priority levels will
restore the circuit breaker to in-service.
In many applications, loads are controlled and grouped
directly out of the BACnet client equipment. If the grouping
is done at the BACnet client workstation, care should
be taken that commands are not sent from the client to
the server device constantly, and faster than they can be
processed by the server. The client should wait for the
BACnet confirmed service response before sending another
BACnet circuit breaker command.
It is common to command the controllable circuit breakers
only on change. It is also possible to configure controllable
circuit breakers into groups in the Pow-R-Command
panelboard, and then configure the BACnet client devices to
control the corresponding group flag. If group flags are used
for scheduling, group objects appear as BACnet Binary Value
objects with instance number of 1 through 16.
If digital inputs (switches, motion sensors or photocells
for example) have been configured, these will appear as
BACnet Binary Inputs objects.
Analog inputs and outputs (light level sensors,
temperatures, dimming ballast outputs, etc.) are
translated in a similar manner.
After installing and configuring the device, the system
can be queried from a BACnet operator workstation. This
process varies greatly from one vender’s client workstation
to another. The system integrator should be familiar with
this process for the specific workstation in question. If no
workstation is available, there are a couple of freeware and
demo BACnet explorer programs available on the Internet
that can be used for testing. Try the following URLs:
http://www.polarsoft.biz/products.html
http://www.chipkin.com/a/resources/BACnet/
http://www.cimetrics.com/products/proddetail.php?prod=B5001
