+AD4- keep in mind that when you connect the ground of the probe to a circuit,
+AD4- that the entire chassis of that scope will be at that potential.


I use an isolation transformer on my scope for this reason, to isolate the
ground from my 120V direct powered projects.  Yes this does leave the scope
case LIVE+ACE-  My boss came in one day while I was doing this, said hello,
leaned on the scope, touched a grounded pipe
and got a lollapaloozer. He was really pissed off, and wanted me to +ACI-fix+ACI-
whatever the problem was.  I told him I really should have a +ACQ-700
differential amplifier front end for my ancient scope, and he hit the
cieling again.  He decided my problem was some two-to-three prong adapter I
had, and banned them from the lab (He's not an EE, and was not really
listening to reason at this point.)

I've exploded more than one scope ground by hooking it up to a live chassis,
where the chassis was plugged into a two-prong plugged in the wrong way, or
the house wiring was wrong and the neutral and hot were reversed in the plug
wiring.  kaPOW+ACE-


--Lawrence

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body