Application Guidelines; Recommended Torques And Screw-In Depths; Behaviour In Fire - ABB POLIM Operating Instructions Manual

3.3.2

Application guidelines

The following guidelines apply for the use of surge arresters in medium-voltage systems
and in railway applications:
ƒ "Application guidelines Overvoltage protection: Dimensioning, testing and application of
metal oxide surge arresters in medium-voltage systems", document 1HC0075561
ƒ "Application guidelines Overvoltage protection: Dimensioning, testing and application of
metal oxide surge arresters in railway facilities", document 1HC0075573
3.3.3

Recommended torques and screw-in depths

Thread Arrester type
Material pairing: steel bolts class 8.8 in aluminum threads of arrester electrodes
M10 POLIM-H
M10 POLIM-H SD
POLIM-R
M10
POLIM-X
M10
MWK/MWD
M12
POLIM-C
M12
POLIM-C
M12
POLIM-C .. LB
M12
POLIM-D/-K/4.5 ID
M12
POLIM-D/-K
M12
POLIM-D without lug
M12
POLIM-D without lug
M12
POLIM-I
M12
POLIM-H
M12
POLIM-X
M12
POLIM-I/-S/-H
M16
POLIM-I/-S/-H
M16
POLIM-X
M16
POLIM-X
M16
Attachment of a disconnecting device (POLIM-D/-K only)
M10 & POLIM-D/-K
M12 disconnector
Material pairing: steel bolts and steel nuts class 8.8 of some clamping accessories
M6
M8
M10
M12
M16
3.3.4

Behaviour in fire

The silicone housing of POLIM® and MWK/MWD type arresters is self-extinguishing.
6 |
Position
support on grading
ring (if present)
top connection
top connection
top connection
top & bottom
top connection
bottom connection
top & bottom
top connection
bottom connection
top connection
bottom connection
top & bottom
top & bottom
bottom connection
top connection
bottom connection
top connection
bottom connection
threads at the
disconnecting device
Screw-in depth [mm]
Required
torque [Nm]
min.
25
30
30
30
50
50
50
30
50
50
50
50
50
50
50
100
100
100
100
20
10
25
50
75
160
Operating instructions | EN | 1HC0141361 AA
max.
10 10
16 16
16 16
15 16
18 23.5
16 20
16 16
– –
20 25
20 20
17 17
12 12
14 14
14 20
18 25
25 25
25 40
23 24
23 25
– –