isolation transformer needed

to

if

g an

the

AC

on

in the

text -

Anyone using an isolation transformer should not become complacent. It is a tool with hazards. Just the same as using a power saw has hazards, but the hazards can be minimized and the user must be vigilant.

text -

An isolation transformer reduces the hazards, no one said it removes them completely. It should be understood that anyone working on live electrical equipment has the capacity to comprehend the dangers or is otherwise advised to entrust the work to someone more competent.

To paraphrase Monty Python . "This thread is getting silly"

How about the technician who assumes that the isolation transformer has decreased the risk of shock and behaves accordingly...without verifying mains isolation before reaching inside live equipment?

Assumptions can be quite shocking!

John :-#)#

"Meathead Plonker"

.... Phil

"sparky is a MORON "

- you brainless PARROTING f****it !!

.... Phil

I swear I have seen documented procedures lifting the ground of an oscilloscope. I though it was Tektronix, but I don't remember the details.

I like using battery scopes and also differential probes.

greg

I have hooked things up with isolation and later found things like a motor short. Works fine with the transformer.

I didn't always first check the customers explanation and plug something in right away before doing anything, but I do it now.

greg

I would agree with this except you also state then, there is no path from secondary hot to primary neutral, which makes no sense in your explanation. In electronic servicing you don't want to ground the secondary making a new neutral. You got to get away from the code to do it.

greg

"GregS" Meathead Plonker "Phil Allison"

You gotta plug it in to do that.

.... Phil

Customer says his unit was emitting smoke and smells. You look at the unit and it smells crisp on first inspection. Are you really going to tell me your going to plug it in first???

Customer says there is sparks from the AC cord where there pet rabbit might have chewed it. You look at it and see bare copper. Your going to plug that in first?

Customer brings in unit that has had liquid poured into it. Are your going to plug that in without tearing it down first?

Most of the time you will plug it in to verify faults. But there are times a visual and smell no power inspection will tell you a lot.

bob

"bob" ( snip smartarse drivel )

Examples he missed from ME in this thread:

" There are a host of other checks and inspections a service tech needs to do on and around the AC wiring, fusing devices and any AC power leads and plugs attached to a unit. Any parts that are damaged, worn out or otherwise seem unsafe must be repaired or replaced.

I go through a LOT of AC plugs, fuses and fuse holders in my work. "

And:

" My post does NOT say that it is the very first step.

It does say that with an unknown but possible PSU fault - connection to a normal RCD protected AC outlet should be done FIRST - before using an isolation tranny.

Obviously, visual inspection comes very first, including carefully checking of the AC plug, lead and fuse if accessible. If the AC fuse is missing or blown, then a major fault is likely.

In the latter case, MY procedure is to install a suitable new AC fuse and gradually bring up the item using a variac - all the time monitoring the current draw from the AC supply with meter specially built for that purpose. If the AC current becomes unusually large ( or the RCD trips) as the AC voltage rises - game over.

.... Phil

Jamie wrote in news:E0b_m.43810$ snipped-for-privacy@newsfe22.iad:

Thanks! Former call was WA5DQP. My 'sine' has been 'bz' (my initials) since my first contacts as WN5DQP/0.

Sorry, no. Played with tty many years ago. A bit of playing with packet stuff. Occasional FM and SSB.

CW is my favorite mode.

I was just tapping out you call sign. Its been a while since I did that. A really long while for the straight key. I remembering trying to tap code while I was in the Army barracks with a temporary setup. I was using two pieces of wire ! That was

Seems my hand goes balistic on your letters. I need some practice though. It was a lot easier doing mine. N6GS.

greg

ah, CW, 30 WPM myself! :) I can send faster!

snipped-for-privacy@zekfrivolous.com (GregS) wrote in news:hhvjl2$ebi$ snipped-for-privacy@usenet01.srv.cis.pitt.edu:

Try tapping out 'BENS BEST BENT WIRE' followed by the 'shave and a hair cut' rhythm. It has a cool beat.

Oh this could go on and on !!