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3-phase unit to operate between 10.5 - 12.7 am-
peres.
Use Equations (16) and (17) to estimate test current,
and allow 5 percent tolerance as explained above.
11.3 Three-Phase Unit (Lower Unit)
A. Use test connections #1 of Figure 25 and set
V
= V
= 30 volts.
1F2F
1F3F
The current required to close contacts of the bottom
unit should be:
Relay Range
.2-4.5
Trip Current Amp
15.3-17.6
∆ Phase-Shifter
set at
Nominal Maximum
Torque Angle θ
m
∆ If maximum torque angle θ
angle, the new
I
I
=
------------------- -
t
then test relay at the new β – angle
11.4 Phase-to-Phase Unit (Top Unit)
a. Use test connection #5; set V
V
fault
Note that to set this voltage; set voltage
V
= V
, first.
1-1F
2-2F
Make sure that,
V
=
V
1 1F
–
2 2F
–
–————–—| Example 5 |———–———
If V
= 120
in
V
= 30
fault
then
V
=
V
1 1F
–
2 2F
–
trim up one of these voltages to set V
at exact value.
Courtesy of NationalSwitchgear.com
.75-21.2
1.3-36.6
3.3-3.38
1.90-2.16
90˚
105˚
105˚
60˚
75˚
75˚
has been changed to a new
m
θ
sin
t
m
(20)
β
sin
= 30 volts =
F1F2
V
–
V
in
fault
(21)
=
------------------------------ -
2
120 30
–
45 volts,
=
--------------------- -
=
2
FAULT
The current required to close contacts of the top
unit should be:
Range
.2 - 4.5
∆ Trip Current
13.3 - 14.7 2.85 - 3.15 1.63 - 1.80
(I
) amperes
t
Phase-Shifter
Set Current
75˚
Lagging V
1F-2F
∆
If maximum torque angle,
new angle, use Equation (20) for trip current limits.
b.Repeat the test using test connections #6 and #7
11.5 Maximum Torque Angle Test
If maximum torque angle test performance is desired
follow instructions under Section13, Calibration al-
lowing ±5
˚
tolerance. Observe the same voltage and
current limits correction as mentioned above when
relay is set for other settings than specified here. The
test currents should be modified by following multi-
plier:
1.07
---------- -
or .2 - 4.5 ohm range
Z
5.03
or .75 - 21.2 ohm range
---------- -
Z
8.7
------- -
for 1.3 - 36.6 ohm range
Z
11.6 Indicating Contactor Switch (ICS)
Close the main relay contacts and pass sufficient dc
through the trip circuit to close the contacts of the
ICS. The current should not be greater than the par-
ticular ICS tap setting being used for the 0.2 - 2.0
ampere ICS. The operation target should drop free-
ly.
The contact gap should be approximately 0.047" be-
tween the bridging moving contact and the adjust-
able stationary contacts. The bridging moving con-
t a c t s h o u l d t o u c h b o t h s t a t i o n a r y c o n t a c t s
simultaneously.
If the electrical response is outside the limits a more
complete series of tests outlined in the Section 13,
Repair Calibration may be performed to determine
which component is faulty or out of calibration.
I.L. 41-490H
.75 - 21.2
1.3 - 36.6
75˚
75˚
θ
, has been changed to a
m
17
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