Graco Inc. UNICARB Pro AA4500 - Manual (Page 24)

24 308936
Electrical Troubleshooting
NOTE: Additional gun troubleshooting can be done on Gun Part No. 236031 using the Remote Spraying Voltage Read-
out (SVR
t). See Accessories to order the SVR.
PROBLEM CAUSE SOLUTION
Reduced fluid efficiency Improper distance between gun and
work-piece
Parts poorly grounded
High booth exhaust velocity
Fluid pressure too high
Improper fluid viscosity
Fluid resistivity too low
No or low voltage output
Turbine alternator not operating
Faulty gun resistance
Fluid leaks from needle packing and
causes short
Faulty turbine alternator
kV switch stuck on low
Adjust spraying distance to 8 to 12 inches
(203 to 305 mm)
Clean hangers; Check for proper ground on
conveyer or track
Reduce exhaust velocity within code limits
Reduce fluid pressure at fluid supply
Check supplier for proper fluid for electro-
static spray
Check fluid resistivity with paint meter and
probe
Check possible causes listed below
Check air supply to turbine inlet; See page 15
Check gun resistance; See page 25
Clean needle cavity; Replace fluid needle;
See page 34
Be sure plug is in place on back of turbine
alternator housing; Remove and test turbine
alternator; See page 36
Check switch actuation; replace if needed
Operator gets shock Operator not properly grounded or is
near an ungrounded object
Gun not properly grounded
Be sure floor is properly grounded; Wear
shoes with conductive soles or wear personal
grounding straps; Be sure operator is not in
contact with or carrying any metallic items
which could build up electrical charge; If
worn, a glove must be conductive or modified
as shown on page 9
See Check the Electrical Grounding,
page 12
Operator gets shock when
touching workpiece Workpiece not properly grounded. Clean workpiece hangers; Check for proper
ground on conveyor or track
No or low voltage output reading
on gun display module Damaged fiber optic cable or
connection Check cables and connections; replace if
damaged
See other causes under Problem –
Reduced fluid efficiency, above
NOTE: If using an ES Display Module, see its instruction manual, No. 308265, for further troubleshooting.