Precaution before Use
CAUTION
When the main unit is under test status, please don’t touch alligator
clipper on test cable. Because the insulation of plastic layer is not
enough, touch it may cause hazard. As Figure 3-4.
Please don’t touch here when
high voltage output
Figure 3-4
<<< Warning ! When the output terminal is cut off. >>>
7. Test complete confirmation
You may touch DUT, high voltage test cable or output terminal etc high voltage areas
under modifying circuit or others test requested conditions. Please confirm the following
at the first.
Power switch is turned off.
As the insulation resistance test unit, DUT may full of high voltage when test is completed.
In the meantime, you need to pay attention to obey descriptions of item 8 and 9 of this
chapter. As the described procedures to execute.
<<< Note! When testing insulation resistance is charging. >>>
8. Charge
When the insulation resistance is testing, DUT, capacitor, test cable, probe and output
terminal even includes the tester are full of high voltage. After turning off the power
switch, it needs a period of time to discharge. Please obeys the above descriptions,
don’t touch any place may cause shock especially on power just turn off.
9. Confirm charging voltage has been discharged completely
The discharged time of charging voltage is depends on testing voltage and DUT
characteristic. To assume that high voltage add to DUT is equivalent to high voltage
add to 0.01uF capacity parallel 100MΩ resistance circuit. When test voltage is 1000V,
then after turned off power, the voltage which add on testing and DUT decrease to lower
than 30V and needed time about 3.5 seconds. When test voltage is 500V, needs about
2.8 seconds. To assume the time constant of DUT is known, if you want to know the
voltage decrease to below 30V needed time. Please follow the above procedures,
multiply needed time of decreasing to below 30V by time constant. As Figure 3-5.
1905x
Figure 3-5
3-3
www.valuetronics.com
To Next Page
Loading...
