Test Barrel Resistance - Graco PRO AA5500SC Instruction Manual

Test Barrel Resistance (See Fig. 27)
Measure the resistance between the barrel contact
ring (26a) and the metal contact pin (E), using a metal
rod (D) and megohmmeter as shown in Fig. 27. Be
careful not to damage or scratch the inner surfaces of
the barrel with the metal rod.
The resistance should be 19 to 29 megohms. If the
resistance is incorrect, make sure the metal contact
pin (E) and the barrel contact ring (26a) are clean.
If the resistance is still outside the specified range:
1. Remove the barrel contact ring (26a) with a small
pick. There is a wire lead in the groove that the
contact ring was removed from.
2. With the metal rod (D) still inside the barrel as
shown in Fig. 27, measure the resistance between
the wire lead and the metal rod.
3. If the resistance is still outside the specified range,
the gun barrel needs to be replaced.
If the resistance is correct, install a new contact
ring (26a) and press it firmly into the groove on the
front of the barrel.
Be sure the contact ring is in place before operat-
ing the gun.
Electrical Tests
Fig. 27
WARNING
FIRE, EXPLOSION, AND
ELECTRIC SHOCK HAZARD
The barrel contact ring (26a) is a con-
ductive contact ring, not a sealing
o-ring. To reduce the risk of sparking or
electric shock, do not remove the barrel
contact ring from the barrel except to
replace it and never operate the gun
without the contact ring in place. Do not
replace the contact ring with anything
but a genuine Graco part.
E
26a
Wire lead in groove
behind contact ring
D
03247B
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