GE PQM II, Instruction Manual

Page: 41 / 216

CHAPTER 2: INSTALLATION
PQMII POWER QUALITY METER – INSTRUCTION MANUAL 2–13
2.2.4 Control Power
The control power supplied to the PQMII must match the installed power supply. If the
applied voltage does not match, damage to the unit may occur. Check the product
identification to verify the control voltage matches the intended application.
A universal AC/DC power supply is standard on the PQMII. It covers the range 90 to 300 V
DC and 70 to 265 V AC at 50/60 Hz. It is not necessary to adjust the PQMII if the control
voltage is within this range. A low voltage power supply is available as an option. It covers
the range 20 to 60 V DC and 24 to 48 V AC at 50/60 Hz. Verify from the product
identification label that the control voltage matches the intended application. Connect the
control voltage input to a stable source for reliable operation. A 2.5 A HRC fuse is
accessible from the back of the PQMII via the fuse access door. Consult the factory for
replacement fuses, if required. Using #12 gauge wire or ground braid, connect Terminals 5
and 6 to a solid system ground, typically a copper bus in the switchgear. The PQMII
incorporates extensive filtering and transient protection to ensure reliable operation under
harsh industrial operating environments. Transient energy must be conducted back to the
source through Filter Ground Terminal (5). The Filter Ground Terminal (5) is separated from
the Safety Ground Terminal (6) to allow dielectric testing of switchgear with the PQMII
wired up. Filter Ground Terminal connections must be removed during dielectric testing.
When properly installed, the PQMII meets the interference immunity requirements of IEC
801 and ANSI C37.90.1.
2.2.5 VT Inputs
The PQMII accepts input voltages from 0 to 600 V AC between the voltage inputs (V1, V2,
V3) and voltage common (Vn). These inputs can be directly connected or supplied through
external VTs. If voltages greater than 600 V AC are to be measured, external VTs are
required. When measuring line-to-line quantities using inputs V1, V2, and V3, ensure that
the voltage common input Vn is grounded. This input is used as a reference for measuring
the voltage inputs.
All connections to the PQMII voltage inputs should be connected using HRC fuses rated at
2 Amps to ensure adequate interrupting capacity.
2.2.6 CT Inputs
Current transformer secondaries of 1 A or 5 A can be used with the PQMII for phase and
neutral sensing. Each current input has 3 terminals: 5 A input, 1 A input, and common.
Select either the 1 A or 5 A terminal and common to match the phase CT secondary.
Correct polarity as indicated in the wiring diagrams is essential for correct measurement of
all power quantities.
The CTs selected should be capable of supplying the required current to the total
secondary load, including the PQMII burden of 0.1 VA at rated secondary current and the
connection wiring burden.
All PQMII internal calculations are based on information measured at the CT and VT inputs.
The accuracy specified in this manual assumes no error contribution from the external CTs
and VTs. To ensure the greatest accuracy, Instrument class CTs and VTs are recommended.