I see your point /ground the scope float the equipment. ----- Original Message ----- From: "Joe Smalley" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, October 14, 2002 1:03 PM Subject: Re: Grounding scope (was: Yet another charger question)
> If the scope is isolated from ground, the chassis is hot to ground. > > If you connect the scope to another piece of gear (like to a PC running > Wavestar) the hot chassis will be shorted to ground through the com cable > and the PC ground. > > If you touch the scope (like many of us are prone to do) then you will get > shocked by the hot chassis. > > Floating the scope is a dangerous and risky practice. > It is much safer to float the equipment. > > If you have a two channel oscilloscope, you can use the difference function > to make measurements. One probe tip goes to ground. The other probe tip goes > to the point you want to measure. The difference plot on the scope shows the > potential between the test points. > > Joe Smalley > Rural Kitsap County WA > Fiesta 48 volts > NEDRA 48 volt street conversion record holder > [EMAIL PROTECTED] > > ----- Original Message ----- > From: "Victor Tikhonov" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Monday, October 14, 2002 12:35 PM > Subject: Grounding scope (was: Yet another charger question) > > > > One must be careful here when working with non-isolated equipment > > such as PFC chargers. > > > > If you want to see/measure the voltage difference between two points > > both of which are at some potential (not grounded), grounded scope > > may cause your device blow up as well as ground pin lead. Been there. > > If the scope is floating (or connected to the mains through isolation > > transformer and then grounded to equipment chassis) you're OK. > > > > You have to know what you're doing. > > > > Victor > > > >
