Impedance Check - ABB KD-10 Instruction Leaflet

41-490J
scribed above, except back off one turn to give ap-
proximately 0.031 inch gap.
14.7 SPRING RESTRAINT
Reconnect for a three-phase fault, Test No. 1 and
set the phase-shifter so that the current lags the volt-
age by:
90° for .2 - 4.5 range
105° for .75 - 21.2 and 1.27 - 36.6 ranges
Adjust the spring so that the current required to close
the left-hand contact is as follows:
0.2 - 4.5
Relay Range
V = V 2.5
1F-2F 1FV3F
I KD-10 1.55- 1.65
trip
I KD-11 1.55 - 1.65
trip
De-energized, the relay spring should open the con-
tacts. Friction in the movement, relay not level, and
electrostatic attraction may contribute to difficulties
in adjusting this point. To avoid these difficulties it is
recommended to level the relay properly, at this
point omit light indicating circuit, and look for smooth
contact action. Friction in bearings or dirt in cylinder
will cause improper action.

14.8 IMPEDANCE CHECK

Use test connections #1 and set V
volts. The current required to close contacts of the
bottom unit should be:
Relay Range
∆ Trip Current
15.3 - 17.6 3.3 - 3.65 1.90 - 2.16
φ Phase-shifter set at
The Nominal M-T-Angle
φ
Phase-shifter settings are always set for 30 ° higher than nom-
inal maximum torque angle to account for phase difference
between phase-to-phase and phase-to-neutral quantities.
The 3φ unit maximum torque angle is always referred to
phase-to-neutral since it receives only one single-phase cur-
rent.
∆
To determine the limits for current when the MTA, θ, is not
equal to nominal maximum torque angle specified, multiply
the nominal values tabulated above by the ratio
where:
θ m = original maximum torque angle
θ = recalibrated maximum torque angle.
20
.75 - 21.2 1.3 - 36.6
10 10
1.22 - 1.28 .710 - .750
1.22 - 1.30 .710 - .765
= V = 30
1F2F 2F3F
.2 - 4.5 .75 - 21.2 1.3 - 36.6
90° 105° 105°
60° 75° 75°
θ
sin
m
--------------- -
θ
sin
Type KD-10 and KD-11 Compensator Distance Relay
14.9 REVERSE REACH CHECK FOR KD-11
(.2 - 4.5 OHM RANGE ONLY)
Use voltage test connection #1 and set voltages
V 1F2F =50 volts and V 2F3F =2 volts; connect current
lead "23" to "terminal 15, and current lead "22" to
lead marked "21". Let phase-shifter for current to lag
V 1F2F voltage by 30 ° this current connection is
equivalent to phase B current lagging V BN voltage
by 60 ° in the reverse directions. Adjust current for
3-phase unit to operate between 10.5–12.7 am-
peres.
15.0 PHASE-TO-PHASE UNIT (TOP
UNIT): PHASE-TO-PHASE UNIT
(T AB AND T BC COMPENSATORS)
MAXIMUM SENSITIVITY ANGLE
ADJUSTMENT
a. Use #5 test connection for T AB compensator,
and #6 test connection for T BC compensator.
b. Measure voltage across C 2A for T AB and
across C 2C for T BC adjustment.
c. Set current and voltages equal to:
Relay Range
V = V
fault 1F-2F
∆
Trip Current (amps)
Phase-shifter set at
current lagging V
∆
For current limits when θ m maximum torque angle, is not 75 °
multiply the values above
torque angle for which the relay was recalibrated.
d. Vary the phase angle in both directions of the set
value, to see that a low voltage across C
No. 5) or C
volt) is obtained at the maximum torque angle
setting. If within ±2 degrees, it can be left undis-
turbed. If the minimum voltage is obtained at
some other angle, readjust phase-shifting resis-
tor or potentiometer P
angle.
,
e. For core and reactor (XL
straint spring as above per Section 13.1, INI-
TIAL SPRING SETTING (clockwise) , page 17.
.2 - 4.5 .75 - 21.2 1.3 - 36.6
30 30
13.9 2.97
75° 75°
(θ )
1F-2F m
sin 75
where β = new maximum
-------------- -
β
sin
(Test No. 6) capacitor (below 1
2C
or P at the desired
2A 2C
) adjustments, set re-
AC
30
1.72
75°
(Test
2A