Operating instructions for POLIM
©
-D surge arrester
ABB
8
EN
Doc. 1HC0010173 AB
3.3.2. Application
guidelines
The following guidelines apply for the use of POLIM
®
-D surge arresters:
•
“Application guidelines Overvoltage protection”
Dimensioning, testing and application of metal oxide surge arresters in me-
dium voltage systems, pamphlet 1HC0075561
Additionally for surge arresters equipped with disconnecing devices applies:
X
Use
POLIM
®
-D surge arrester equipped with a disconnecting device in out-
door installations, only.
X
Use the disconnecting device with POLIM
®
-D surge arrester, only.
3.3.3.
Recommended torques and screw-in depths
The specified values in the table below apply for steel bolts of strength class 8.8 in
aluminum nut threads.
Thread Position Torque
[Nm]
Minimum
screw-in depth
[mm]
Maximum
screw-in depth
[mm]
M12 top
connection 48
18
25
M12
top connection
without socket
48 18
20.5
M12
bottom
connection
48 18
20.5
M12
bottom connection
without socket
48 12
12.5
The specified values in the table below apply for POLIM
®
-D surge arrester equip-
ped with a disconnecting device
Thread
Position Torque
[Nm]
M12
bolt between disconnecting device and bottom con-
nection of surge arrester
20
M10
bolt of the disconnecting device
20
3.3.4. Behaviour
in
fire
The silicone housing of the surge arrester is self-extinguishing.
