Specifications

COMPLETE REVISION
PIP ELSSG01
October 2004 Design and Fabrication of Low-Voltage Metal-Enclosed AC Power Circuit Breaker Switchgear
Process Industry Practices Page 7 of 14
c. Self-tapping bolts and screws shall not be used.
d. Copper compression type lugs shall be provided if indicated on the
purchaser’s PIP ELSSG01D Data Sheet.
4.3.6 The ground bus shall be firmly secured in each vertical section.
4.3.7 If a neutral bus is indicated on the purchaser’s PIP ELSSG01D Data Sheet, it
shall extend the full length of the switchgear and be insulated from ground.
4.3.8 Unless indicated otherwise on the purchaser’s PIP ELSSG01D Data Sheet,
the neutral bus shall have the same continuous current rating as the phase
bus.
4.4 Voltage Transformers
4.4.1 Voltage transformers for metering or protective relaying purposes shall be
protected by disconnecting-type current-limiting primary fuses.
4.4.2 Secondary voltage shall be 120 volts, with primary voltage as indicated on
the one-line diagram.
4.4.3 Each transformer shall have a fused secondary winding.
4.4.3.1 Secondary fuses shall be located in the low-voltage control
compartment.
4.4.3.2 Fuse holders shall be labeled to indicate size and type of fuse and to
identify the transformer (e.g., Phase “A” PT).
4.5 Control Power Transformers
4.5.1 The primary fuses shall coordinate with the magnetizing inrush current and
the secondary protection of the control power transformer.
4.5.2 The kVA rating of the control power transformer(s) shall be determined by
the supplier, taking into account any additional loads external to the
switchgear, as indicated on the purchaser’s PIP ELSSG01D Data Sheet.
4.5.3 A form C contact shall be provided for remote alarming of any loss of
control power.
4.5.4 Secondary voltage shall be 240/120 volts, with primary voltage as indicated
on the one-line diagram.
4.5.5 Primary and secondary windings shall be protected by disconnect-type
current-limiting fuses.
4.5.6 Transformers shall be located in the low-voltage control compartment.
4.6 Current Transformers
Current transformers for metering or protective relaying purposes shall be rated in
accordance with purchaser’s PIP ELSSG01D Data Sheet or the one-line diagram.