Sensing Transformers Settings - Basler BE1-11g Instruction Manual

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Sensing Transformers Settings

The BE1-11g requires information about the current and voltage transformers to provide metering, fault
reporting, fault location, and protective relaying.
Sensing transformer settings are configured on the Sensing Transformers settings screen in
BESTCOMSPlus. A summary of the settings appear at the end of this section.
BESTCOMSPlus Navigation Path: Settings Explorer, System Parameters, Sensing Transformers
HMI Navigation Path: Settings Explorer, System Parameters, Sensing Transformers
CT Setup
The BE1-11g requires setting information on the CT ratios. This setting is used by the metering and fault
reporting functions to display measured quantities in primary units.
Unbalanced Calculation Method
Unbalanced overcurrent protection is provided by the 50 and 51 elements. Two methods are available to
calculate unbalanced current.
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Method 1 (I2/I1)
2
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Method 2 (Average)
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where:
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MIN =
MAXp = maximum of all three phases
MINp = minimum of all three phases
Connection
This setting defines how the sensing CTs are connected for differential metering.
Phase VT Setup
The BE1-11g requires setting information about the VT ratio, the phase connections, and the operating
modes for the 27/59 and 27R functions. These settings are used by the metering and fault reporting
functions to display measured quantities in primary units. The voltage input circuit settings also determine
which power measurement calculations are used. Most of these connections such as 3W-D, 4W-Y, AN, or
AB are self-explanatory.
Auxiliary VT Setup
The auxiliary voltage input (Vx) connection can be set for AB, BC, CA, AN, BN, CN, or Ground. When set
for one of the phase voltages, the sync-check function can be set to compensate for the phase angle
difference relative to the reference voltage measured at the three-phase voltage inputs. The Vx input
connection is set to Ground when connected to a source of ground unbalance voltage or residual voltage
such as a generator grounding resistor, broken delta VT connection, or capacitor bank star point.
Configuration
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× MIN
BE1-11g