Phase Voltage Inputs (Io_B Module) - GE MM300 Instruction Manual

CHAPTER 2: INSTALLATION
Phase voltage inputs
(IO_B module)
MM300 MOTOR MANAGEMENT SYSTEM – INSTRUCTION MANUAL
while phase B and C would both read the magnitude of phase C. If on the other hand,
phase B was lost, at the supply, phase A would be 180° out-of-phase with phase C and the
vector addition would equal zero at phase B.
The MM300 has three channels for AC voltage inputs. There are no internal fuses or ground
connections on the voltage inputs. Polarity is critical for correct power measurement and
voltage phase reversal operation.
Figure 2-20: Wye voltage connection
Contactor
A
B
C
To switchgear
ground bus
Control power
Figure 2-21: Delta voltage connection
Contactor
A
B
C
To switchgear
ground bus
Control power
– +
N L E1 E2 E3
VT1 VT2
Phase voltage inputs
MM300
Motor Management System
– +
N L E1 E2 E3 E4
VT1 VT2
Phase voltage inputs
MM300
Motor Management System
ELECTRICAL INSTALLATION
E4 E5 E6 E7 E8
VT3 N/C
853735A2.CDR
E5 E6 E7 E8
VT3 N/C
853736A2.CDR
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