Adjustment Of The Fuse Tripping; Fuse Tripping. Control - ABB NAL Series Mounting And Operation Manual

1. The split pin (7) is removed and the release shaft (1) together
with the drive ring (2) is pushed in the direction of the arrow until
the tapped connection is free from disc (3).
2. The release rod (1) with the drive ring (2) is turned and ajusted
to a hole in the disc (3), while the ajustment of the fuse trip flap
(15) and its distance to the strike pin of the fuse link must be
checked, see Fig. 28.
Remark:
– Following adjustment according to above the fuse switch di-
sconnector must open by when tested in all phases,
– after fuse interruption the mechanism shall be blocked against
another operation until the fuse link has been replaced.

8.3 Fuse tripping. Control

1. Turn the operating mechanism shaft clockwise, max 60°, and
return the operating handle back to the neutral position (ope-
ning spring housing F, see Fig. 31, must not be latched),
Fig. 28 Fuse tripping | Fig. 29 Tripping rod | Fig. 30 Fuse tripping comlpeted | Fig. 31 A-mechanism
Fig. 28
3–6 mm
Fig. 30
15 14 13
7 5 6 7
12 NAL/NALF/VR – Mounting and operation manual
max. e÷8 mm
e (DIN 43625)
8 9 10
1 2 3 4
12 11
2. Mount a new fuse-link, or a test fuse which is in accordance
with DIN 43625, in one of the phases. Dimensionally the fuse
link then will have the same dimensions as ABB-CEF fuse-links,
3–6 mm
3. If the distance between the fuse clips is longer than described
– max e + 8 mm, the ajustment (point 6.3) must be made with
the fuse link resting on the fuse clips on the fuse base,
4. The distance between the striker pin and the fuse trip flag
(15) must be from 3-6 mm. By this adjustment the fuse link is
allowed to sag, but the distance between the striker pin and the
fuse trip flag must not exceed 12 mm,
5. If the fuse switch disconnector does not open when adjusted
as mentioned above, the adjustment has to be checked and
repeated.
Remark:
– the hooks (12) on the release rod (1) ought to have the same
position as shown on Fig. 29 - when the fuse switch disconnector
is in open position with both operating springs uncharged, but
with the releasing spring charged (ref. point 1).
15 14 13
7 5 6 7
Fig. 29
11
Fig. 31
MEC.
max. e÷8 mm
e (DIN 43625)
8 9 10
1 2 3 4
12 11
1
MEC.