627-500
21
INSTALLATION
Step 23
Make up the terminal pad connections.
NOTE:
Torque values apply only to the
¹⁄₂
-i nch h a rdwa re de scr ibed a nd not t o
connectors used to secure primary leads of
voltage transformers or surge arresters to
the bus.
(a)
For aluminum terminal pads to tinned-
copper or tinned-bronze connectors
(untinned-copper or untinned-bronze
connectors are not recommended), use
¹⁄₂
-inch galvanized steel hardware, with one
Belleville washer (not furnished) against the
aluminum terminal pad and one galvanized
steel fl at washer against tinned connector,
as shown in Figure 17, Detail A. Tighten
steel bolts to 50 foot-pounds using a torque
wrench. If a torque wrench is not available,
tighten until the Belleville washers are fl at,
and then back off one-half turn. Do not use
lockwashers with Belleville washers.
(b)
For aluminum terminal pads to alumi-
num connectors
, use
¹⁄₂
-inch aluminum or
galvanized steel hardware with two Bel-
leville washers (not furnished) as shown in
Figure 17, Detail B. Tighten aluminum bolts
to the manufacturer’s specifi cations. Tighten
steel bolts to 50 foot-pounds using a torque
wrench. If a torque wrench is not available,
tighten until the Belleville washers are fl at,
and then back off one-half turn. Do not use
lockwashers with Belleville washers.
Figure 17. Terminal pad connections for aluminum terminal
pads.
Copper connector
Aluminum connector
Belleville
washers
Aluminum
terminal pad
Flat washer
Aluminum
terminal pad
Detail A,
for aluminum terminal pads to
tinned-copper or untinned-bronze connectors
Detail B,
for aluminum terminal pads to
aluminum connectors
