Precautions For Withstand Voltage Test And Insulation Resistance Measurement; Test Preparation; After Completion Of The Test - Panasonic YD-350GL4 Operating Instructions Manual

10.3 Precautions for withstand voltage test and insulation resistance measurement
Make sure to work at least 5 minutes after the power is turned off.
The capacitor may still have some voltage left even if the power switch is turned off. To prevent a
physical accident caused by an electric shock or a spark,
The withstand voltage test and the insulation resistance
measurement shall be performed by service engineers
specified by Panasonic representatives, or educated and/
or skilled persons who well undersand and/or who are
familiar with welders and electricity.
Performing the withstand voltage test and the insulation
resistance measurement carelessly may damage this unit
as the unit is equipped with semiconductor parts including
transistors.
If your internal regulations define to carry out these
●
test, observe the following "Test preparation" and "After
completion of the test" and (The following procedure is
10.3.1 Test preparation
Connection cables and signal wires
■
1 Turn off power at distribution box (customer
（ ）
preparation) and then disconnect the input cables
from the load side terminal of the distibution box and
from the input power terminal of this unit.
Turn off power to all related devices (jigs).
2 Disconnect cables and signal cables connected to
（ ）
the following terminals and connectors.
• Front: Base metal terminal (-), Torch terminal (+),
Feeder connector and
Base metal voltage detection terminal.
• Inside: Two jig terminals
Primary side
■
3 Short-circuit the unit input terminals collectively (total
（ ）
3 terminals).
4 Turn the power switch ON side.
（ ）
5 Short-circuit between the anode (wire #7) and cathode (wire
（ ）
#8) of the diode D1
10.3.2 After completion of the test
WARNING
CAUTION
Maintenance and inspection
If power is ON without
removing the jumper bar for
test, devices may be damaged
or burnt out.
Unless cables removed for test
are returned, the unit may not
operate or may malfunction.
explained under the condition with the top panel and
the right and left panel removed.
Prepare jumper cables (cross section 1.25 mm2
●
approx.) with a clip to short-circuit each device.
When cables and connectors are disconnected, put
●
tags or take notes so that they can be re-installed in
place correctly.
See also sections "Circuit diagram", "Parts layout" and
●
"Parts list".
The capacitors may still have voltage. Wait for 5
minutes or more after the power is OFF before
starting to work.
7 Short-circuit load side terminal of IGBT-Q1(wire #11),
（ ）
load side terminal of IGBT-Q2 (wire #10),
load side terminal of IGBT-Q3 (wire #12).
and load side terminal of IGBT-Q4 (wire #13).
8 Collectively short-circuit the above 3, 5 and 7.
（ ）
Secondary side
■
9 For diode D2 and D3(D2,D3,D4,D5 for 500GL 4),
（ ）
short-circuit their own anode and cathode respectively.
10 Short-circuit the base metal (-) terminal (128) and
（ ）
the torch (+) terminal (130).
Primary and secondary side
■
11 Further collectively short-circuit the above 8 and 10.
（ ）
Case ground cable
■
12 Disconnect two case ground cables on the middle
（ ）
plate and three case ground cables on the bottom
plate.
PC board
■
13 Disconnect all the connectors connected to the PC
（ ）
board.
Remove all the short-circuited cables for the test and
return the disconnected cables as they were according to
the following procedure.
Reconnect the ground cables and connectors on the
●
PC board as they were.
Return the dust cover, top panel, right panel, and left
●
panel as they were.
Connect the input power cable to the input terminal
●
and return the terminal cover.
Connect the input power cable to the power box
●
switch.
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