GE 469

CHAPTER 5: SETTINGS
469 MOTOR MANAGEMENT RELAY – INSTRUCTION MANUAL 5–19
PHASE CT PRIMARY: “350”
MOTOR FULL LOAD AMPS: “330”
GROUND CT: “50:0.025”
5.3.2 Voltage Sensing
PATH: SETTINGS ZV S2 SYSTEM SETUP ZV VOLTAGE SENSING
The manner in which the voltage transformers are connected must be entered here. A
value of “None” for
VT CONNECTION TYPE indicates that no voltage measurement is
required. Note that phase reversal is disabled for single VT operation. All voltages are
assumed balanced. Also, frequency is only available for AN or AB connections.
The
ENABLE SINGLE VT OPERATION settings is seen only if the VT CONNECTION TYPE is
“Open Delta” or “Wye”.
If voltage measurements are to be made, the turns ratio of the voltage transformers must
be entered. The
VOLTAGE TRANSFORMER RATIO must be chosen such that the secondary
voltage of the VTs is between 40 and 240 V when the primary is at
MOTOR NAMEPLATE
VOLTAGE. All voltage protection features that require a level settings are programmed as a
percent of the
MOTOR NAMEPLATE VOLTAGE or rated voltage, where MOTOR NAMEPLATE
VOLTAGE represents the rated design voltage line to line.
For example, given the motor nameplate voltage as 4160 V and the VTs are 4160/120
Open Delta, set the voltage sensing settings as follows:
VT CONNECTION TYPE: “Open Delta”
VT RATIO: “34.67:1”
MOTOR NAMEPLATE VOLTAGE: “4160”
5.3.3 Power System
PATH: SETTINGS ZV S2 SYSTEM SETUP ZV POWER SYSTEM

VOLTAGE [
VT CONNECTION
TYPE:
Range: Open Delta, Wye, None
MESSAGE
ENABLE SINGLE VT
OPERATION: OFF
Range: AN, BN, CN, OFF or AB, BC, OFF
MESSAGE
VOLTAGE TRANS-
FORMER
Range: 1.00:1 to 300.00:1 in steps of
0.01
MESSAGE
MOTOR NAMEPLATE
VOLTAGE: 4000 V
Range: 100 to 36000 V in steps of 1

POWER [
NOMINAL SYSTEM
FREQUENCY: 60 Hz
Range: 50 Hz, 60 Hz, Variable
MESSAGE
SYSTEM PHASE
SEQUENCE: ABC
Range: ABC, ACB
MESSAGE
SPEED2 PHASE
SEQUENCE: ABC
Range: ABC, ACB