5-3. Removing Case and Measuring Input Capacitor Voltage

Y Significant DC voltage can remain on capacitors af- ter unit is Off. Always check the voltage as shown to be sure the input capacitors have discharged be- fore working on unit.

1

1

2

3

+ lead to lower right terminal, – lead to upper right terminal

Tools Needed:

5/16 in

Turn Off welding power source, and disconnect input power.

1 Outside Handle Screws

To loosen top, remove two outside handle screws from both handles and all side bolts.

2Interconnecting Board PC2

3Voltmeter

Measure the dc voltage across the screw terminals on RC3 and RC5 as shown until voltage drops to near 0 (zero) volts.

Proceed with job inside unit. Rein- stall cover when finished.

ST-802 260 / ST-801 536

OM-188 422 Page 25

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Miller Electric 456 CV, 456 CC manual Removing Case and Measuring Input Capacitor Voltage