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2.
For TR compensator, use procedure out-
lined above, except use #3 connection and
adjust R2R when required.
3.
For TC compensator, use connection #4,
omit voltage connection to terminal 7,
disconnect LC-lead, and adjust R2C when
required as per Part I.
D.
Three-phase unit (T compensator) of all KD
type relays:
1.
Use connection #l.
2.
Measure
VOltage
3.
Set the current equal to:
V1F2F
1.5 Relay Setting
The current should be high enough to pro-
vide an accurate phase angle meter reading,
or any convenient value if a phase-shifter
is used for direct angle reading.
4.
Set the phase-shifter for the desired maxi-
mum torque angle value.
Note the voltage.
5.
Vary phase angle in both directions of the
set value, to see that a low voltage (below
1 volt) is obtained at the maximum torque
angle setting. If minimum voltage is with-
in +2 degrees, do not readjust. If the mini-
mum voltage is obtained at some other angle
readjust phase-shifting resistor or potentio-
meter at the desired angle.
E.
Suggested Procedure for Detecting and
Replacing Defective C3C Capacitor
For KD-4, KD-5
Step 1
Set S = 1 for the 3-phase unit.
Apply approximately 120 volts to relay terminal 7
and 8 and short out terminals 7 and 9 (for KD-5
between terminals 6 and 9 and some short reach
KD-4).
If contacts of the 3-phase unit close, then, the
C3C capacitor is under suspicion but im-
across C3A
and
KD-10 Relays
properly adjusted R3A can be suspected, as
well.
Step 2
Remove the connections made in Step 1.
Apply approximately 120 volts (i.e., 100-130
volts) to: terminals 8 and 9 = Vg9.
Measure the voltage across the C3C capacitor
with a high impedance voltmeter - 5000
OHMS/volt.
For .75-20 OHM reach KD-4 relays, the
minimum_ .voltage should be Vmin = 3.72 x
Vg9. If Vmin less than 3.72 x Vg9 replace
capacitor C3C.
For .24.35 OHM reach KD4 and KD-5
relays, the minimum voltage should be Vmin
= 2.82 x Vg9 if Vmin less than 2.82 x Vg9,
replace capacitor C3C.
For all ranges KD-10 use same procedure as for
OHM reach.
.75-20
Step 3
Relays which fail either step 1, or have C3C
capacitor replaced after failing step 2, or
after C3A capacitor
readjustment of R3A or P3A. Repeat step 1 and
adjust R3A or P3A so that
Measure total R3F and R3A resistance
Omit this procedure for KD- 10 relays.
a) for .75-20 OHM reach KD-4 relays
when the relay is preheated as per I.L.,
l
decrease R3A setting by 10% of total
R3F and R3A resistance.
or
for a cold rela
l
R3A so that th
further adjustment is required.
b) for .2-4.35 OHM reach KD-4 relays with
sub "A" in the style number
for a cold relay, decrease R3A setting
l
8% of total R3A + R3F resistance.
for a hot relay, decrease R3A setting
l
8% of total R3A + R3F resistance.
I.L. 41498.5
replaced, require
iS
open.
c o n t a c t s jUSt
repeat step 1 and adjust
e contact just opens. No
3
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