How To Change Rated Current, Tripping Characteristic And Leak Tripping Characteristic Series Earth Leakage Circuit Breakers (Electronic Overcurrent Tripping Type) - Mitsubishi Electric C Series Handling And Maintenance

2.3.7 How to change rated current, tripping characteristic and leak tripping characteristic of
earth leakage circuit breakers (electronic overcurrent tripping type)
NV100-SEP, NV100-HEP
NV250-SEW, NV250-HEW
Leakage indicator
(comes out at leak tripping)
175
150
125
Ir (A)
Current
setting
Long time-delay
operating time
Step setting type:
Long time-delay operating time T
Short time-delay tripping current I
Short time-delay operating time T
Pre-alarm current I
Continuously adjustable type:
Current setting Ir
Instantaneous trip current I
• For setting sensitivity current and operation time, open the cover in the
same procedure as for tripping characteristic setting.
• A slotted head screwdriver of 4.5mm width and 0.6mm thickness is
suitable for the setting.
• Stopping in the middle of each set values makes sensitivity current or
operating time unstable in some cases.
Be sure to set exactly at the position of each set value.
• At setting refrain from applying force more than necessary as such can
cause failures.
(Adequate operation torque is 0.05N·m maximum.)
Trip (PTT) button
Replacement
label
Cover screw
Dial
For setting, turn
the arrow of each
dial to the scale po-
sition desired
4 5 6 . 2 8 10
60
80 . 1
12
200 7
3
6
8
4 16
225 12 100 2 10 .06 . 3
T (S) I (×Ir) T (S) I (×225A)
L S S i
Short time-delay
operating time
Instantaneous
Short time-delay
tripping current tripping current
L
S
S
P
i
Fastening torque
0.9~1.2N•m
OVER LED (Red)
PAL LED (Yellow)
70% LED (Green)
Sensitivity current setting dial
Operation time setting dial
(for time delay type)
Test button
Setting dial
Rated current label
Test cover
. 8 . 9
. 7 1. 0
I (×Ir)
P
Pre-alarm
current
Seal attaching
position
SEALED
(1) Take off the seal, if sticked.
(2) Loosen the cover screw and open the cover.
(3) Set tripping characteristics by turning the dials.
For turning the dials for characteristic setting,
use a screwdriver as illustrated at left.
1 A slotted head screwdriver of 3 mm width
and 0.5 mm thickness at the top is suitable
for the setting
2 At setting, refrain from applying force more
than necessary as such can cause failures.
(Adequate operation torque is 0.02N·m
maximum.)
3 Except for the dials of current setting lr and
instantaneous tripping current l
arrow of the setting dials within the range of
the thick line of setting value.
Stopping the arrow in the middle may ad-
vance the set value to the next one in some
cases.
* As for Is setting, a set value may advance
to the next one in some cases.
(4) The blank labels may be used for indication of
the current setting Ir. Please fill in the blank la-
bel with oily ink, and stick the label to the posi-
tion under the handle.
(5) Close the cover and fasten the screws.
(6) Stick the seal, if it is necessary.
For setting, turn the arrow of each
dial to the scale position desired.
, keep the
i
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