Introduction; Application - GE CLPG12C Instructions Manual

GEI-83910
CARRIER CURRENT GROUND RELAY
CLPG12C
I NTRODUCTI ON
The CLPG12C is a high-speed, zero-sequence ground relay designed specifically
for use as a ground-fault relay in directional-comparison relaying schemes. This
relay contains one high-speed zero-sequence directional unit, which may be
po 1 ari zed from voltage and/or current.
It
also contains two hi gh-speed zero-
sequence non-directional overcurrent units and one direct-current-operated (DC)
aux
il
i ary unit. The CLPG12C is packaged ina s i ze-L2 case and i ncl udes a target
and a separate seal-in unit. One CLPG12C is required per terminal.
APPLICATION
The CLPG12C finds application on grounded neutral systems as the directional-
comparison ground relay in directional-comparison schemes, regardless of the type
of channel that is used. This relay, operating in conjunction with the pilot
channel and the CLPG12C relays at the other ends of the protected 1 ine section,
provides high-speed tripping for all single-phase-to-ground faults in the protected
line section.
The two non-di rect i ona 1 overcurrent uni ts and the operat i ng ci rcu i t of the
directional unit may be all supplied in series from the neutral connection of the
three line-current transformers. The polarizing circuit of the directional unit
may be supplied from a current transformer in the neutral of a grounded neutral
power transformer or from the broken-delta secondary connection of three potential
transformers whose primary windings are connected in wye, or it may be
simultaneously supplied from both sources of polarization.
These instructions do not purport to cover all details or variations in equipment nor provide {or every
possible contingency to be met in connection wilh inst.allation, operation or maintenance. Should {urther
in{ormation be desired or should particular problems arise which are not covered sufficiently for the purchaser's
purposes, the matter should be referred to the General Electric Company.
To the ex/ent required the products described herein meet applicable ANSI, IEEE and NEMA
standards; bllt no such assurance is giuen with respect to local codes alld ordinances because they vary greatly.