Bridge Test - Graco ULTRA 500 Instructions-Parts List Manual

BRIDGE TEST
perform this test to determine if the bridge is functional.
Remove the bridge from the pressure control box and
continuity tester, such as multi-meter set on the
X1
See Brldge Rectifier Replacement, page 24. Use a
ohms scale
( 0
1.
the bridge fails even one
test, it
must be replaced.
Eight individual checks, or tests, must be performed. If
Fig
12 shows the position of the wires on the bridge. Us-
ing the chart at the right, connect the meter wires as in-
dicated by the black dots for each test, then check the
Continuity.
In Tests 1, 2 and 3, there should be NO continuity.
In Tests 4,5 and 6, connect the
+
and
-
meter wires as
indicated, check continuity, then switch the meter wire
connections and check continuity again. You should
get
NO
continuity one way, and
YES
continuity the
other way.
In Tests 7 end 8, connect the meter wires as indicated
by the black dots. Touch the indicated
" G
wire to one
meter wire, and then to the other.
You
should get NO
continuity one way, end
YES
continuity the other way.
Fig
12
. .