Westinghouse HKB Instructions Manual

O
WESTINGHOUSE TYPE HKB SINGLE POLE
CARRIER RELAYING AND RECLOSING
GENERAL
This scheme provides
and reclosing for phase to ground faults, and
three pole tripping and
for phase faults including two line to ground
faults. This is, for all internal phase A-to­
ground faults, only the
circuit breakers of both ends of the protected
line will be opened.
phase B pole will be operated for phase B-to­
ground faults and only phase C pole for phase
C-to-ground faults. For
the opened pole will be
at each end.
any internal three-phase, phase-to-phase,
On
or two-phase-to-ground
of the circuit breaker
med iate reclosing for
tional, that is, three
provided if d esired or
can be blocked.
The back-up relays used
type HKB Single pole carrier relays provide
separate independent protective system,
back-up relays trip all three poles and may be
directional overcurrent,
pedance, etc. If the types
HZM d istance relays and
attachments are used, then a time d elay relay
is necessary to d elay the instantaneous back­
up relays from tripping all three poles until
carrier relays have had an opportunity to
the
trip single pole.
COMPONENTS OF
COMPLETE EQUIPMENT
The relay components of the type
pole carrier system consis�s of the following:
1 Type Carrier Relay and Auxiliaries
HKB
1 Type H�S Phase Selector Relay
1 Type .HZM-3 Distance Relay
3
Type SGR-12 Reclosing Relays as Req.
as Req. Type SG and MG Auxiliary Relays
NEW INFORMATION
P E R A T
INSTRUCTIONS
single pole tripping
reclosing (optional)
phase A pole of the
In a like manner, only
each of these faults
reclosed immed · i ately
fault all three poles
will be opened. Im­
these faults is op­
pole reclosing can be
three pole reclosing
to supplement the
a
These
d irectional im­
.HZ Impedance or
instantaneous trip
Single
HKB
O N O F
This list d oes not includ e phase and ground
back-up relays which
relay system.
OPERATION
The schematic connections for a typical type
HKB single pole system
The type
3 to 6 HKB
•
in the same manner as d escribed
600.3. The common tripping
relay are supervised by the types
3 relays as sho•,rn on
"Carrier Trip Circuits".
the following operating characteristics :
The type HQS phase
nected to receiver negative sequence current
from a three-phase negative sequence filter
energized by the current transformers and the
residual current from
the current transformers.
to-ground faults, the zero sequence components
of all three phases are essentially in phase
with the negative sequence component
faulted phase. This
ground fault, for example, the phase A phase
element will have
selector
torque while the phase B and C elements will
have contact-opening torque, since the B and C
components of negative
essentially 120° out of
tive sequence component
phase.
On all d ouble line--to-ground-faults,
three zero sequence components are essentially
phase with the negative sequence component
in
of the unfaulted phase,
a phase B-C to-ground fault.
phase phase selector
A
contact .closing torque while the phase B and C
elements will not,
sequence components of these
EFFECTIVE JANUARY 1949
I.L. 41-600.7
S C H E M E
provide an ind ependent
figs .
is shown in
relay itself operates
in 41-
I.L.
contacts of this
HQS
and HZM-
unrl.er
in figure 4
These relays have
selector relay is con­
the neutral circuit of
On all single line­
of the
means on a phase-A-to­
contact closing
sequence current are
phase with the nega­
of the unfaulted
the
For example, consider
In this case the
element will receive
because the negative
two phases are