BLASTING CAP BY GRASPINC THE
(4) Remove shunt.
(5) Hold one cap lead wire to one post
of galvanometer and touch other lead wire to other post.
(6) If cap is satisfactory, galvanometer
needle will deflect slightly less than it did when the
instrument was tested.
(7) Dispose of defective
placing with material being detonated.
PROTECT BLASTING CAPS FROM
BEING STRUCK OR COMPRESSED
BY OVERBURDEN THAT IS PLACED
Figure 5-8. Testing the galvanometer.
EXPLOSIVES BEING READIED FOR
DO NOT PLACE
DEFECTIVE CAPS TOO CLOSE TO
· HEN UNCOILING CAP LEAD
THE MAIN DETONATING CHARGE.
WIRES, THE CAP WILL NOT BE
HELD DIRECTLY IN THE HAND, BUT
(8) Shunt lead wires of all caps
WILL BE HELD BY THE WIRES
immediately after testing. Wires will remain shunted
APPROXIMATELY 2.5 CENTIMETERS
until connection to firing circuit.
(1 INCH) FROM THE CAP.
c. Firing Wire. The firing wire may be tested on
the reel, but must be retested after unreeling as
STRAIGHTENED OUT BY HAND. DO
uncoiling may separate broken wires. Firing wire will be
NOT THROW, WAVE, OR SNAP TO
tested as follows:
(1) Separate firing wire at both ends.
(2) Carefully extend cap lead wires to
Touch wires at one end to galvanometer posts. The
needle should not move. If needle moves, there is a
short circuit in firing wire. Locate and repair as required.
(3) Secure cap to prevent movement
by placing in a hole or behind a barricade.
(2) Shunt wires together at one end and
touch those at other end to galvanometer posts. This
should cause a wide deflection of needle.
AN INDIVIDUAL REMOVING THE
movement of the needle indicates a break in firing wire.
SHUNT WILL GROUND HIMSELF TO
A slight movement indicates a point of high resistance
PREVENT ACCUMULATED STATIC
which could be caused by several strands of multi-
ELECTRICITY FROM FIRING THE
stranded wire being broken or by wires not being clean.
Locate defect and repair as required.