ABB KD-10 Instruction Leaflet

ABB ABB
ABB ABB
Effective : November 1999
Supersedes 41-490H Dated March 1997
( ) Denotes Change Since Previous Issue
!
Before putting protective relays into service,
make sure that all moving parts operate freely, in-
spect the contacts to see that they are clean and
operate the relay to check the settings and electri-
cal connections.
1.0 APPLICATIONS
The type KD-10 relay (Figure 1, page 35), is a
polyphase compensator type relay which provides a
single zone of phase protection for all three phases. It
provides essentially instantaneous tripping for
phase-to-phase faults, two-phase-to-ground faults,
and three-phase faults within the reach setting and
sensitivity level of the relay.
The type KD-11 relay (Figure 1), is similar to the
KD-10 relay except that the characteristic impedance
circle for the 3-phase unit includes the origin. This re-
lay is usually applied as a carrier start relay in direc-
tional comparison blocking schemes but it may also
be used for time delay tripping in non pilot distance re-
laying. Both KD-10 and KD-11 relays have indicating
contactor switches rated 0.2/2.0 amperes. The 2.0
ampere tap must be used for directional comparison
blocking (KA-4) applications. The 2.0 ampere target is
recommended for direct trip applications. The 0.2 am-
pere target is recommended where a 125 or 250 volt
lockout relay (WL) is energized and 2.0 ampere
where a 48 volt lockout relay is used.
Refer to Instruction Leaflet 40-208 for a description of
how the KD-10 relay is used in directional comparison
blocking systems.
For time-distance applications the KD-10 and KD-11
relays are used with the TD-4, TD-52 or TD-5 dc tran-
All possible contingencies which may arise during installation, operation or maintenance, and all details and
variations of this equipment do not purport to be covered by these instructions. If further information is
desired by purchaser regarding this particular installation, operation or maintenance of this equipment, the
local ABB Power T&D Company Inc. representative should be contacted.
Printed in U.S.A.
ABB AUTOMATION INC
Substation Automation and Protection Division
Coral Springs, FL 33065
CAUTION
Type KD-10 and KD-11
Compensator
Distance Relay
sistorized timers. See Figure 19 (page 50) and Fig-
ure 24 (page 53) for the external schematics for 3
zone protection, using the TD-4 and TD-52 relays,
respectively. For further discussion see Section 9,
External Connections.
Fault detectors are used to supervise the trip circuit
for those applications where line side potentials are
used or loss-of-potential supervision is desired.
Otherwise, undesired tripping may occur on line os-
cillations or loss-of-potential. The cylinder type
KC-2 or KC-4 relay (2-8 amperes) is recommended.
The plunger or other magnetic attraction type relays
(e.g., a three unit SC relay or a three unit ITH relay)
may be used if the fault detector contacts carry trip
coil current rather than auxiliary relay (e.g., auxiliary
trip unit, timer, etc.) current.
The SC or ITH relay may also be used if a slow
dropout contact (e.g., TX contact of TD-5 timer re-
lay) is available to be connected around the fault
detector contacts.
2.0 CONSTRUCTION
The type KD-10 and KD-11 relays consist of the fol-
lowing: three single air gap transformers (compen-
sators, Figure 2, page 36), three tapped auto-trans-
formers, two cylinder type operating units, and an
ICS indicating contactor switch.
2.1 COMPENSATOR
The compensator, which is designated T (Figure 3,
page 36), is a two-winding air gap transformer with
one primary current winding. The compensators,
which are designated T
AB
ing air gap transformers with two primary current
windings. Each primary current winding has seven
Instruction Leaflet
41-490J
and T , are three-wind-
BC