Miller OM-246 466B, Руководство пользователя

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OM-246 466 Page 52
7-4. Removing Cover and Measuring Input Capacitor Voltage
!
Turn Off welding power
source, and disconnect in-
put power.
!
Significant DC voltage can
remain on capacitors after
unit is Off. Always check the
voltage as shown to be sure
the input capacitors have
discharged before working
on unit.
Remove lifting eyes, top cover and
side panels.
1
Power Interconnect Board
PC2
2 Voltmeter
Measure the dc voltage across the
+ bus terminal and − bus terminal on
PC2 as shown until voltage drops to
near 0 (zero) volts. Measure input
capacitor voltage on both inverter
assemblies before proceeding.
3
Typical Bleeder Resistor
An example of a typical bleeder
resistor is shown on this page.
Proceed with job inside unit.
Reinstall cover when finished.
Tools Needed:
5/16 in.
802 985 / 243 896-A
1
2
+ lead to left bus terminal, − lead to right bus terminal
3
Typical Bleeder Resistor
#16 AWG 1000 volts dc
insulation rating, approx
3 in. (76 mm) leads
25 to 1000 ohm, 5
watt resistor