Precautions For Withstand Voltage Test And Insulation Resistance Measurement; Test Preparation; After Completion Of The Test - Panasonic YC-400TX4 Operating Instructions Manual

8.3 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 outthesetest, observe the following "Test preparation"
and"Aftercompletion of the test" and (The following procedureis
panel and the right and left panel removed.
● Prepare jumper cables (cross section 1.25 mm2 approx.) with a clip to short-circuit eachdevice.
● When cables and connectors are disconnected, put tags or take notes so that they can be re-installedinplace
correctly.
● See also sections "Circuit diagram", "Parts layout" and "Parts list".

Test preparation

8.3.1
As numerous transistors and semi-conductor components are used in this machine, careless insulation pressure
tests and measuring of the machine.
The following points should be strictly observed in the event any of these tests are carried out in accordance with
your company regulation.
a. Disconnect cable from distribution box which is connectedto three input terminals and short-circuit the three
inputterminals.
b. Disconnect the secondary side current cable connected totwo output terminals and short-circuit the two
outputterminals.
c. Short-circuit the anode and cathode of the main circuitprimary diode D1,the emitter and collector of the
maintransistor Q1-Q2, the anode and cathode of the secondarydiode D2 — D3 and thyristor.
d. Remove case grounding.(The case is grounded by a fast on terminal totalling 6 locatio

After completion of the test

8.3.2
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 thePC 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.
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.
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explained under the condition with the top