Ransburg 9040, Service Manual

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9040 Low Voltage Control Unit Kit- Maintenance
Control Unit Output Test
When a lack of high voltage at the applicator
indicates a problem, perform a Control Unit
Output Test on the control unit to determine
whether it is at fault.
Equipment Required: Ransburg
LTST5000 LV Control Unit Test
Assembly
1. Turn control unit power OFF and remove low
voltage cable from control unit.
2.
Connect tester cable to control unit.
3.
Move switch on tester to FRONT PANEL kV
METER position.
4.
Turn control unit ON and adjust control unit
high voltage adjust knob fully clockwise.
5.
Read the control unit front panel kV meter.
Reading should be rated kV of applicator ±5 kV.
turn the control unit OFF.
If the voltage read correctly, the problem is not
in the control unit and the low voltage cable and
applicator should be checked for the cause. If
proper readings are not obtained, the problem
is with the control unit. Consult the
“Troubleshooting Flowchart” in this section to
locate the specific problem.
NOTE
>
The LTST5000 Test Assembly can
also be used to test the low voltage
cable. Consult the LTST5000 service
manual for further information on using
the LTST5000 Test Assembly.
PC Board Test Jumper
To assist in testing and troubleshooting, a jumper
(JP4) has been incorporated on the 9040 PC
board. By covering (shorting) both terminals the
high voltage on relay is triggered. Thus, for testing
and troubleshooting, high voltage output can be
obtained without the need to trigger the applicator
or user supplied control device. Just remember to
reposition the jumper after testing, so that it
covers only one terminal (open) or the high
voltage will stay on all the time. (See “Figure 4 -
Main PC Board” for location of test jumper JP4.)
! C A U T I O N
>
If JP4 is left covering (shorting)
bother terminals, high voltage will be on
whenever AC power is turned on. This
could be hazardous in some
applications.
Theory of Operation
Line voltage (90-264 VAC) is applied to input
terminals 8PL-1 and 8PL-2 of power supply 1
SUP through the user supplied exhaust fan and
conveyor interlocks, fuse IFU, and ON/OFF
switch 1SW.
The output of power supply 1SUP, through PC
board fuse F2, provides the DC voltage which
powers the PC board regulators and the AC
Power ON LED. The DC input to the oscillator
circuit is obtained from a board regulator
through high voltage adjust knob 1POT. The
oscillator circuit outputs a low voltage, high
frequency AC signal through the low voltage
cable socket 3SOC to the applicator. The high
voltage cascade located in the applicator
rectifies the AC voltage to DC and steps it up to
provide rated kV. The high voltage adjust knob
controls the level of output voltage from the
oscillator to the high voltage cascade. In this
manner, complete adjustability from 0 to
maximum kV of the applicator is achieved.
CP-11-01 28