hi there.

i have one monitor here 2232bw

I want to supply the power/inverter board with 220v and measure on that board.the question is what to connect to that board to not have a sparkle when measuring ?

thanks in advance

/i have not connected power board to mainboard and CCFLs

I hope to be understood

 

If you use a battery powered multimeter there should be no problem measuring voltages anywhere on the board. Just don’t short anything when connecting the probes.

And, if course, don’t touch anything on the board with your hands. For more personal safety, use an isolation transformer to power the board.

 

If you don't use a isolation transformer, make sure the board is plugged into an outlet protected by a GFCI breaker.
That will minimize your chances of a serious electrocution.

 

Even a GFCI will not protect against a shock in a setup as described. And an isolation transformer will not provide any protection at all when both sides of the mains are involved.
It seems like the TS wants to measure voltages for the backlight tubes in a flat screen monitor.
My caution is that it is a hazardous undertaking with the possibility of contacting lethal voltages, and if the TS is not already familiar with the means to do it safely I suggest not doing it at all.
The hazard is "Risk of Death."

 

Even a GFCI will not protect against a shock in a setup as described. And an isolation transformer will not provide any protection at all when both sides of the mains are involved.

Of course there is always the danger of electrical shock when testing equipment, if you simultaneously touch two different points with high voltage between them.
The purpose of an isolation transformer or GFCI is to prevent the danger of getting electrocuted from touching a single high voltage point while being in contact with earth ground.
It also prevents a large current flow if you accidentally connect the ground of an earth-grounded instrument, such as an oscilloscope, to a hot lead.