7. Glossary
7.1 Terms and abbreviations
Term
Abbreviation Explanation
Action
The pre-defined set of actions that an alarm initiates. Also known as fail class.
Alternating current
AC
Alternating current
module 3.1
ACM3.1
A replaceable PCB with voltage and current measurement inputs. Used in the DEIF
controller.
Apparent power
S
The 3-phase apparent power, measured in kVA.
Blackout
The busbar voltage is less than 10 % of the nominal voltage, and all generator
breakers are open.
Breaker
A mechanical switching device that closes to connect power sources to the busbar,
or to connect busbar sections. The breaker opens to disconnect the power sources
or to split the busbar.
Busbar
The copper conductors which connect the power sources to the power consumers.
Represented on the single-line diagram as the line that connects all the power
sources and power consumers. If the bus tie breaker is open, there are two
separate and independent busbar sections. Similarly, if the bus tie breaker is
closed, there is only one busbar.
Commissioning
The careful and systematic process that takes place after installation and before
the system is handed over to the operator. Commissioning must include checking
and adjusting the controller.
Common terminal
COM
This is generally connected to either a power source, or the supply return. See the
wiring examples for more information.
Configuration
Assigning input and output functions to terminals, and setting parameters, so that
the controller is suitable for the application where it is installed.
Connected
A generator is connected to the system if it is running, synchronised with the
busbar, and its breaker is closed.
Controller
DEIF equipment that measures system conditions and then uses outputs to make
the system respond appropriately.
Controller
GPU
GPU 300, DEIF's Generator Protection Unit.
Current transformer
CT
CustomLogic
The ladder logic system included in the controller software, which can be
configured for customised responses to measured or calculated values.
Digital input
DI
Terminals on a controller hardware module that the controller uses to measure a
digital input. A pre-configured digital input function or alarm can be assigned to the
input.
Direct current
DC
Firmware
Software that is installed in the controller. This software enables the controller to:
process inputs and outputs, display operating data, keep track of the equipment
status, and so on.
Generator breaker
GB
The breaker between a genset and the busbar. The controller can control a
generator breaker.
GPU 300 Commissioning guidelines 4189341033 UK
www.deif.com
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