In NORMAL use, after correct installation, the G Clamp is not intended to be hand-held or hand-manipulated
by the OPERATOR during measurements or tests.
After a suitably rated 4mm fixed-shroud plug has been connected to the 4mm socket in the screw head,
the area on the head side of the finger guard is rated CATEGORY IV 600V and provides REINFORCED
INSULATION against 8kV transient impulse.
The area on the threaded side of the finger guard should be treated as HAZARDOUS LIVE at all times.
SPRING LOADED BRASS CONTACT PIN
G CLAMP BODY
FLUTED RING NUT
FLUTED SCREW HEAD WITH
MOULDED M16 THREAD
FINGER GUARD
SHROUDED 4mm SOCKET
HOLD G CLAMP FIRMLY
WHILE TIGHTENING
FLUTED SCREW
AND FLUTED RING NUT
BRASS CONTACT IS FULLY COMPRESSED
WHEN MOULDED SCREW TOUCHES BUS BAR.
CONTACT FORCE = 40N +/- 5N
OPEN G CLAMP
ENOUGH TO FIT OVER
BUS BAR
TYPICAL BUS BAR
MOUNT G CLAMP
ONTO TOP EDGE OF
BUS BAR
2. TIGHTEN
FLUTED RING NUT
BY HAND,
45° MAX, (ONE FLUTE).
1. TIGHTEN LARGE
FLUTED SCREW HEAD
BY HAND ONLY,
45° MAX
(ONE FLUTE).
ALLOW AT LEAST
35mm CLEARANCE
FOR DRUMMOND
4mm PLUG.
NOTE THAT OTHER
DESIGNS OF 4mm PLUG
MAY REQUIRE
CONSIDERABLY
MORE CLEARANCE
45° MAX
45°
MAX
12
12
14
14
22
22
HAZARDOUS LIVE
HAZARDOUS LIVE
CATEGORY IV 600V
CATEGORY IV 600V
50
52
35
87
87
ALLOW CLEARANCE FOR
HEAD OF FUSEHOLDER
ALLOW AT LEAST 75mm CLEARANCE
TO WITHDRAW FUSEHOLDER
ACCESIBLE FUSE
75
FUSEHOLDER
FUSEHOLDER
DISCONNECT 4mm PLUG
BEFORE UNSCREWING FUSEHOLDER.
TIGHTEN FUSHOLDER ONLY FINGER TIGHT.
ENSURE THAT FUSE 6.35 x 32mm IS
CORRECTLY MATCHED TO APPLICATION
4. MAINTENANCE
4.1 Fuse Replacement
The Fused Drummond G Clamp is supplied as standard with a 6.35 dia X 32mm, 600V, 0.5A, 50kA ceramic
HRC rated fuse, but this may have been changed for a different fuse rating at the time of initial installation.
A fuseholder body containing the fuse is housed inside the main screw of the Fused G Clamp.
Disconnect 4mm plug from end of Fuseholder Body.
Unscrew fuseholder Body to access fuse according to the picture. The G Clamp itself does not need to be
disturbed.
Replace the fuse ONLY with the precise fuse specified for the installation.
Screw Fuseholder Body back into place.
Check security of G Clamp.
Apply suitable safety checks before re-connecting 4mm Plug, which will apply power immediately to the
installed wiring.
Spare fuses are available from Martindale Electric using order code FUSE500 (pack of 3).
