Careful and professional installation of the
switchgear is one of the fundamental conditions of
trouble-free circuit breaker operation.
•
Install the mechanism enclosure in the panel
without distortion, placing a dished washer under
the nut and bolt head at each of the four mounting
points (depending on the order).
•
Connect the main terminals without any residual
tension or pressure forces, exerted for example by
the conductor bars.
•
When connecting the conductor bars, the bolts
must be inserted to the depth shown on the
dimensional drawing.
•
Observe the tested terminal zone where
appropriate.
•
Use DIN bolts of tensile class 8.8 together with
dished washers to fasten the conductor bars.
•
Only use the tightening torques shown in the
following table.
•
Remove any contamination (see also section
7.3.1.).
Recommended
tightening torque (
1
)
Nm
Lubricant (
2
)
Thread
without (dry)
Oil or grease
M 06
10.5
4.5
M 08
26
10
M 10
50
20
M 12
86
40
M 16
200
80
(
1
) The rated tightening torques for fasteners without lubrication are
based on a coefficient of friction for the thread of 0.14 (the actual
values are subject to an unavoidable, partly not inconsiderable,
spread).
Rated tightening torques for fasteners with lubrication in accordance
with DIN 43 673.
(
2
) Thread and head contact surface lubricated.
Any tightening torques which deviate from those in the general
table (e.g. for contact systems or device terminals) are to be taken
into account as stated in the detailed technical documentation. It is
recommended that the threads and head contact surfaces of screws
should be lightly oiled or greased, so as to achieve a precise rated
tightening torque.
VM1-T
- VACUUM CIRCUIT BREAKER
10
—
5. Installation and mounting of the breaker
Summary of Contents for VM1-T
Page 43: ...MEDIUM VOLTAGE PRODUCTS 43 ...
