Maintenance; Input Filter Capacitor Discharge Procedure - Lincoln Electric RED-D-ARC ES 275I Operator's Manual

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WARNING
ELECTRIC ShOCK
• Have an electrician install and service
this equipment.
• Turn the input power off at the fuse
box before working on equipment.
• Do not touch electrically hot parts.
• Prior to Performing preventative main-
tenance, perform the following capaci-
tor discharge procedure to avoid elec-
tric shock.
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INPuT FILTER CAPACITOR
DISChARGE PROCEDuRE
1. Turn off input power or disconnect input power
lines.
2. Remove the 5/16" hex head screws from the side
and top of the machine and remove wrap-around
machine cover.
3. Be careful not to make contact with the capacitor
terminals that are located in the top and bottom of
the Power Board.

MAINTENANCE

can kill.
FIGuRE D.1 — LOCATION OF INPuT FILTER CAPACITOR TERMINALS.
POWER
BOARD
RIGHT SIDE OF MACHINE
INSULATED
4. Obtain a high resistance and high wattage resistor
(25-1000 ohms and 25 watts minimum). This resis-
tor is not supplied with machine. NEVER USE A
SHORTING STRAP FOR THIS PROCEDURE.
5. Locate the four capacitor terminals (large hex head
cap screws) shown in Figure D.1. One pair at the
top and one pair at the bottom of the Power Board.
6. Use electrically insulated gloves and insulated pli-
ers. Hold body of the resistor and connect resistor
leads across the two capacitor terminals. Hold
resistor in place for 10 seconds. DO NOT TOUCH
CAPACITOR TERMINALS WITH YOUR BARE
HANDS.
7. Repeat discharge procedure for the capacitor on
other two terminals.
8. Check voltage across terminals of all capacitors
with a DC voltmeter. Polarity of capacitor terminals
is marked on PC board above terminals. Voltage
should be zero. If any voltage remains, repeat this
capacitor discharge procedure.
UPPER
CAPACITOR TERMINALS
GLOVES
ES 275i
LOWER
CAPACITOR
TERMINALS
POWER
RESISTOR
INSULATED
PLIERS
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