Graco ULTRA 1000 Instructions-Parts List Manual page 18

TYPE
OF PROBLEM
ELECTRICAL SHORT
Building circuit breaker opens
as soon as sprayer switch is
turned on.
Any short in any part of thl
CAUTION
motor power circuit, which i'
connected to the output sidl
of the bridge,
will
cause thl
bridge to burn out immediate
ly. Correctly diagnose an(
repair all shorts before check
ing and replacing bridge
Building circuit breaker opens
as soon as sprayer is plugged
into outlet and sprayer is NO1
turned on.
Sprayer circuit breaker opens
after sprayer operates for only
5 to 10 minutes.
WHAT TO CHECK
If
check
Is OK, go to next check
I. Check all electrical wiring for damaged in-
sulation, and all terminals for loose fit or
damage. Be sure to check wires between
pressure control and motor which are encas-
ed in conduit
( 2 2 1 .
See page
29.
2. Check for missing inspection plate gasket
metal to metal contact points which could
(see page
22).
bent terminal forks or other
cause a short.
3. Check motor armature for shorts by using an
armature taster (growler) or perform spin
test.
See page 19. Inspect windings for
burns.
1. Check bridge
1308)
by substituting with a
good bridge or by performing bridge test.
See page 20.
armature is determined to be good. A bad
CAUTION: Do not pmform this check until
armature
will immediately burn out a good
bridge.
I.
Check 'Basic Electrical Problems' on page 14
!.
Check ON/OFF switch (303) See page
23.
Be sure the sprayer is unplugged1 Disconnec
wires from switch and check switch with
finity with the ON/OFF switch OFF. and zerc
ohm meter. The ohm metar shouid read in-
with the switch ON.
CAUTION: A short in the motor circuit wii
burn the bridge out immediately, which in turr
usually causes the ON/OFF switch to fail in thf
closed mode.
.
Check electrical supply with volt meter.
Meter should reed 105 to 125
VAC.
:.
Check tightness of pump packing nut. Over-
tightening nut tightens packings on rod,
restricts pump action, end damages
packings. Sea page 28.
'
.
.
Check stall pressure. Remove the plug from
the top of the fluid filter, and install
a 5ooo
p s i
I 3 5 0
bar1 fluid-filled pressure gauge. See
page 27. Plug in and turn on sprayer. Slowly
should stall at
2&w-3ooo
psi (196-207 bar).
increase pressure setting to maximum. Pump
Turn off and unplug sprayer.
.
After determining that there is no short in
system, reset circuit breaker button.
WHAT TO DO
When check la not
OK
refer to this colum
1. Repair or replace any damaged wiring or ter
minals. Securely reconnect all wires.
2. Correct faulty conditione.
3.
Replace motor. See page
30.
4. Replace bridge. See page 24.
2. Replace ON/OFF switch. See page
23.
1. If voltage is too high, do not operate sprayel
until corrected.
2. Loosen packing nut. Check for leaking
around throat. Replace pump packings, if
necessaly. See manual 307-793.
3.
Calibrate pressure control. See page 27.
1. If circuit breaker continues to open (button
pops up), replace the circuit breaker. See
page 24.
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307-785
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