Winco DGC-2020 - Manual (Page 58)

3-10 DGC-2020 Functional Description 9400200990 Rev K
Generator Exerciser
The unit will start at the designated time and will run for the specified duration. The breaker will be closed
if “Run with Load” is checked in the generator exerciser settings. This mode is independent of the other
self-starting modes.
Mains Fail Transfer Functionality
If mains fail transfer is enabled, the unit will run when the utility is determined to be bad, and will not stop
until the utility has been determined to be good and the load has been transitioned to the utility. This
mode is independent of the other self-starting modes.
Run with Load Logic Element
When the run with load logic element start input is energized, the unit will start, close its breaker, and take
on load at the programmed load rate. If the unit is the only one on the load, it will provide the full load.
When the run with load logic element stop input is energized, the unit will unload at the programmed load
rate, open its breaker, and stop. This mode works in conjunction with demand start/stop, otherwise it is
completely independent of the other self-starting modes.
Engine Run Logic Element
When the engine run logic element start input is energized, the unit will start. When the engine run logic
element stop input is energized, the unit will unload if loaded, open its breaker if needed, cool down, and
then stop.
Demand Start/Stop Function
If the system demand is above the configured level setting for the specified time, and sequencing is
enabled, the unit will start, close its breaker, and take on load at the programmed load rate. Note the unit
will not start if sequencing is not enabled. If the unit is the only one on the load, it will provide the full load.
If the load drops below the stop level for the specified time, the unit will unload at the programmed load
rate, open its breaker, and stop. This mode works in conjunction with the run with load logic element,
otherwise it is completely independent of the other self-starting modes.
Interoperability of the Run with Load Logic Element and the Demand Start/Stop Function
These two functions can be used together; they are not independent of each other. Either one can start or
stop the system, but they can share functionality in that one can stop the system even if the other one
started it. Thus, if a machine was started by pulsing the run with load start, it could be stopped by demand
start/stop. This can be useful in a scenario where it may be desired to start a number of generators all at
the same time but sequence some off if the load does not require them. Run with load start could be
pulsed on all the units causing them to start and close their breakers, then demand start/stop and
sequencing could cycle them on and off as the load requirements change.
BREAKER MANAGEMENT
Introduction
The DGC-2020 is capable of controlling the generator breaker and the mains breaker. Once it is
determined that a valid breaker request is available, the DGC-2020 will attempt to operate the breaker if
possible. The user can choose to control only the generator breaker, the generator and mains breakers,
or none. BESTCOMSPlus is used to configure breaker management. Refer to Section 4,
BESTCOMSPlus Software, Breaker Management, for setting information.
Determining Breaker Status
The status of the breakers is determined by using BESTlogic+ Programmable Logic to setup the
GENBRK and MAINSBRK logic blocks. These logic blocks have outputs that can be configured to
energize an output contact and control a breaker as well as inputs for breaker control and status.
Processing Breaker Requests
Types of breaker operate requests include:
 Local Request - generated by internal functions and based on operating modes.
 Com Request - generated through a communication port using BESTCOMSPlus or the front panel
HMI.
 Logic Request - generated from the PLC (programmable logic controller).