Term
Abbreviation
Explanation
Supervisory control
and data acquisition
system
SCADA
Switchboard
The cabinet where the power sources are connected to the power consumers. See
Busbar too.
Switchboard control
SWBD control
A controller operating mode. Power management and operator commands to the
controller are disabled. The operator controls the system using the switchboard. The
controller monitors operation, and the controller protections are active (that is, if an
operating value activates an alarm, the controller does the alarm action).
System
The gensets, the other power sources, all breakers, the busbars, and all their
controllers. Within the system, the DEIF controllers work together to supply the power
required safely and efficiently.
Third-party equipment
Equipment other than the DEIF controller. For example: The genset, the genset engine
control system, the wiring, the busbars, and the switchboard.
Tie breaker
TB
Used to connect/disconnect the emergency busbar from the main busbar. The
EMERGENCY genset controller can control a tie breaker. (Note: The breaker between
two main busbars is called a bus tie breaker.)
Time
t
Time delay
An alarm must exceed its set point continuously for the period in its Time delay
parameter before the alarm is activated.
Transmission control
protocol/internet
protocol
TCP/IP
The Internet protocol suite. It provides end-to-end connectivity by specifying data
handling.
Trip
An emergency or fast opening of a breaker. No attempt is made to de-load the breaker
before it opens.
United Kingdom
UK
United States of
America
US, USA
The USA sometimes requires different technical standards. They also use their own
system of units.
Universal serial bus
USB
Communication protocol.
UL 94
A plastics flammability standard released by Underwriters Laboratories of the USA.
Voltage
V
Electrical potential difference. U is used as an abbreviation for voltage in most of
Europe, Russia and China.
Voltage and
frequency
V & Hz
For certain controller actions, both the voltage and frequency must be within the
specified range. For example, for busbar OK, or to start synchronising a genset to the
busbar.
Voltage transformer
VT
A transformer for a voltage measurement, so that the voltage at the controller is within
the controller's specifications.
19.2 Units
19.2.1 Units
The table below lists the units used in the documentation, as well as the US units where these are different. In the documentation,
the US units are given in brackets, for example, 80 °C (176 °F).
DESIGNER'S HANDBOOK 4189340911K UK
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