COMEM CRS Manual De Instrucciones página 5

Assembly on the transformer tank
Make a hole with diameter D (see Table 6) in the tran-
sformer tank, ensuring there are no uneven surfaces that
could cause problems for correct operation of the bu-
shing. The stud bolts for securing the bushing (see Table
6) must be placed along a circumference of diameter
D0-D3 coaxial with the hole made previously (Figure 1).
Position the gasket provided (Figure 1).
The bushing must be positioned as shown in Figure 2,
apply a tightening torque of 30 Nm (15 Nm in case of
250/630 A bushing) to fix the nuts on the flange. Connect
a ground tap of the CRS bushing to a stud bolt with the
cable provided (Figure 3). The end of the cable with the
cable terminal diameter 5.3 mm must be correctly secured
to the ground tap using the material provided. The other
end of the ground wire must be secured to a stud bolt
using a nut and washer. Before performing any operations
check that there are no traces of paint on the contact
surface. The ground wire must be installed to ensure an
electrical contact with minimum resistance.
Rated current [A]
250
630
1250
2000
3150
5000/6300
Table 1
Cable terminal with 13 mm hole, washer, nut
Cable terminal with 5.3 mm
hole, screw
Figure 3
Recommended torque [Nm]
12
20
30
55
60
Flag screw: 40
Ground wire
Ground tap
Electrical connection
CAUTION
Electrical connections may only be carried out by qualified,
skilled personnel trained in the applicable health and safety
regulations of the relevant country.
Care must be taken over electrical connection to avoid
ionization phenomena.
Choose the section of the connections to be used and connect
them applying the torque recommended in Table 1 as a function
of the rated current of the porcelain bushing.
Rated current (A)
250
630
1250
2000
3150
4500
6300
5000-8000
Table 2
Thread of bolt
M10
M12
M16
Table 3
Figure 4
CAUTION
When the wires are connected to an upper terminal connector
(figure 7) tighten the bolts with a torque as in table 2. Make
sure that the connection is well performed in order to avoid
overheating.
Recommended torque (Nm)
12
20
30
55
60
75
110
115
Recommended torque (Nm)
25
40
90
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