"Wild_Bill Top Poster from Hell"

My point,

** The only point you have, pal, is on the top of you fat head.

was that you're not going to teach anyone proper grammer or composition
on usenet..


** Could not be plainer that you did NOT understand the issue

AT ALL !!!!!!!!!!!!!!!!!!



..... Phil

In article ,
Michael A. Terrell wrote:
If using a proper isolating transformer, there will be no reference to
ground even with a 'live' chassis. The only way to get an electrical shock
is to touch both outputs from the transformer.


Not true. You connect the chassis of the UUT to the test equipment,
so ANY voltage you contact inside the UUT is referenced to ground.

Why is the test equipment grounded?

--
*Hard work pays off in the future. Laziness pays off now *

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (Rabid Pommy Nut Case) "


Not true. You connect the chassis of the UUT to the test equipment,
so ANY voltage you contact inside the UUT is referenced to ground.

Why is the test equipment grounded?


** Not merely stupid, but dangerously ****ing STUPID !!





..... Phil

"Dave Plowman (News)" wrote:

In article ,
Michael A. Terrell wrote:
If using a proper isolating transformer, there will be no reference to
ground even with a 'live' chassis. The only way to get an electrical shock
is to touch both outputs from the transformer.

Not true. You connect the chassis of the UUT to the test equipment,
so ANY voltage you contact inside the UUT is referenced to ground.

Why is the test equipment grounded?


Yawn... Why are people stupid?


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

In article ,
Michael A. Terrell wrote:

"Dave Plowman (News)" wrote:

In article , Michael
A. Terrell wrote:
If using a proper isolating transformer, there will be no
reference to ground even with a 'live' chassis. The only way to
get an electrical shock is to touch both outputs from the
transformer.

Not true. You connect the chassis of the UUT to the test
equipment, so ANY voltage you contact inside the UUT is referenced
to ground.

Why is the test equipment grounded?


Yawn... Why are people stupid?

Yawn. You really do need to sort out how to work in a safe environment.
All it needs is some common sense. Do you ground one side of a battery DVM
too?

--
*Why doesn't glue stick to the inside of the bottle?

Dave Plowman London SW
To e-mail, change noise into sound.

On Mon, 14 Jun 2010 10:48:38 +1000, "Phil Allison"
wrote:


"Dave Plowman (Rabid Pommy Nut Case) "


Not true. You connect the chassis of the UUT to the test equipment,
so ANY voltage you contact inside the UUT is referenced to ground.

Why is the test equipment grounded?


** Not merely stupid, but dangerously ****ing STUPID !!





.... Phil


Phil: consider it to be "self correcting" instead...

"PeterD"

Phil: consider it to be "self correcting" instead...


** If only that were true ...



... Phil

On Mon, 14 Jun 2010 10:08:43 +0100, "Dave Plowman (News)"
wrote:

In article ,
Michael A. Terrell wrote:

"Dave Plowman (News)" wrote:

In article , Michael
A. Terrell wrote:
If using a proper isolating transformer, there will be no
reference to ground even with a 'live' chassis. The only way to
get an electrical shock is to touch both outputs from the
transformer.

Not true. You connect the chassis of the UUT to the test
equipment, so ANY voltage you contact inside the UUT is referenced
to ground.

Why is the test equipment grounded?


Yawn... Why are people stupid?

Yawn. You really do need to sort out how to work in a safe environment.
All it needs is some common sense. Do you ground one side of a battery DVM
too?

Dang, you confirm stupidity... Amazing! Any test equipment DESIGNED to
not be grounded isn't grounded. And test equipement that is designed
to be grounded damned well better be grounded.

In article , "Dave Plowman (News)" wrote:
In article ,
JW wrote:
On Fri, 11 Jun 2010 10:30:56 +1000 "Phil Allison"
wrote in Message id: :


"JW"

Can anyone recommend a good isolation transformer for sale on-line?

** What kind ??

There are two:

1. Galvanic isolation - for use on a service bench.

Galvanic. Thanks - didn't realize there are different kinds. Don't want
to kill myself!

It certainly seems to me stupid to have the same name for different
devices like this. What is the point of an isolating transformer which
doesn't isolate?


Noise reduction.


greg

In article , JW wrote:
On Fri, 11 Jun 2010 08:24:36 -0500 Chuck wrote in Message
id: :

On Thu, 10 Jun 2010 09:44:12 -0400, JW wrote:

Can anyone recommend a good isolation transformer for sale on-line?
Need one that will handle 5 amps or so at 120VAC, and have a standard AC
plug at the outlet. Prefer one for less than $100 or so, unless that seems
unreasonable. Found one at Mouser for $114 but that's only good for 1.25A.
Getting lots of irrelevant hits on google...

Thanks.


MCM Electronics has one. Chuck

Thanks Chuck. Looking at these for the moment:
http://www.mcmelectronics.com/produc...N--IS500-/28-1
0160
http://www.mcmelectronics.com/produc...-1097-/72-1097

The Tripp-Lite device has secondary attached to GROUND. This is NOT
want you want. All Tripp-Lite supplies are attached to ground forming a new neutral to
make a noise reduction device, period.

I hope the second device has ground isolation.

Greg

In article , "Dave Plowman (News)" wrote:
In article ,
wrote:
That would be news to large numbers of electronics technicians who had
to use an isolation transformer when servicing TVs and other 'live
chassis' consumer electronics. There IS a reason the advice was 'to
always keep one hand in your pocket'.

If using a proper isolating transformer, there will be no reference to
ground even with a 'live' chassis. The only way to get an electrical shock
is to touch both outputs from the transformer.


Proper is the key. I would say over 98% of so called isolation transformers
are for noise control, not serving chassis.

Greg

In article , (GregS) wrote:
In article , JW
wrote:
On Fri, 11 Jun 2010 08:24:36 -0500 Chuck wrote in Message
id: :

On Thu, 10 Jun 2010 09:44:12 -0400, JW wrote:

Can anyone recommend a good isolation transformer for sale on-line?
Need one that will handle 5 amps or so at 120VAC, and have a standard AC
plug at the outlet. Prefer one for less than $100 or so, unless that seems
unreasonable. Found one at Mouser for $114 but that's only good for 1.25A.
Getting lots of irrelevant hits on google...

Thanks.


MCM Electronics has one. Chuck

Thanks Chuck. Looking at these for the moment:
http://www.mcmelectronics.com/produc...ON--IS500-/28-
1
0160
http://www.mcmelectronics.com/produc...-1097-/72-1097

The Tripp-Lite device has secondary attached to GROUND. This is NOT
want you want. All Tripp-Lite supplies are attached to ground forming a new
neutral to
make a noise reduction device, period.

This is the description in the specs...............

Neutral to ground bonding at the secondary eliminates common mode noise and provides an isolated ground reference for sensitive
equipment

What they really mean is a new ground to neutral reference. They make it confusing.
For testing chassis, you need a ground isolating isolation transformer.

greg

I hope the second device has ground isolation.

Greg

On Sat, 12 Jun 2010 07:01:32 -0400, JW wrote:

On Fri, 11 Jun 2010 08:24:36 -0500 Chuck wrote in Message
id: :

On Thu, 10 Jun 2010 09:44:12 -0400, JW wrote:

Can anyone recommend a good isolation transformer for sale on-line?
Need one that will handle 5 amps or so at 120VAC, and have a standard AC
plug at the outlet. Prefer one for less than $100 or so, unless that seems
unreasonable. Found one at Mouser for $114 but that's only good for 1.25A.
Getting lots of irrelevant hits on google...

Thanks.


MCM Electronics has one. Chuck

Thanks Chuck. Looking at these for the moment:
http://www.mcmelectronics.com/produc...S500-/28-10160
http://www.mcmelectronics.com/produc...-1097-/72-1097

A bit more than I wanted to spend and a little less current capability,
but those may be the breaks.

Check out stock number 72-6670 isolation transformer $65.00. We've
had one for years and it works very well. Chuck

In article ,
PeterD wrote:
Yawn. You really do need to sort out how to work in a safe environment.
All it needs is some common sense. Do you ground one side of a battery DVM
too?

Dang, you confirm stupidity... Amazing! Any test equipment DESIGNED to
not be grounded isn't grounded. And test equipement that is designed
to be grounded damned well better be grounded.

If you are isolating the equipment you're working on for safety reasons
doesn't it make sense to use isolated test gear too?

--
*How can I miss you if you won't go away?

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
GregS wrote:
If using a proper isolating transformer, there will be no reference to
ground even with a 'live' chassis. The only way to get an electrical
shock is to touch both outputs from the transformer.


Proper is the key. I would say over 98% of so called isolation
transformers are for noise control, not serving chassis.

Then they should have a different name.

--
*If you don't like the news, go out and make some.

Dave Plowman London SW
To e-mail, change noise into sound.

In article , "Dave Plowman (News)" wrote:
In article ,
GregS wrote:
If using a proper isolating transformer, there will be no reference to
ground even with a 'live' chassis. The only way to get an electrical
shock is to touch both outputs from the transformer.


Proper is the key. I would say over 98% of so called isolation
transformers are for noise control, not serving chassis.

Then they should have a different name.


Thats what I said before !!!!

greg

"Dave Plowman (News)" wrote:

In article ,
PeterD wrote:
Yawn. You really do need to sort out how to work in a safe environment.
All it needs is some common sense. Do you ground one side of a battery DVM
too?

Dang, you confirm stupidity... Amazing! Any test equipment DESIGNED to
not be grounded isn't grounded. And test equipement that is designed
to be grounded damned well better be grounded.

If you are isolating the equipment you're working on for safety reasons
doesn't it make sense to use isolated test gear too?


No.


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

On Sun, 13 Jun 2010 23:16:44 +0100, "Dave Plowman (News)"
wrote:

In article ,
Michael A. Terrell wrote:
If using a proper isolating transformer, there will be no reference to
ground even with a 'live' chassis. The only way to get an electrical shock
is to touch both outputs from the transformer.


Not true. You connect the chassis of the UUT to the test equipment,
so ANY voltage you contact inside the UUT is referenced to ground.

Why is the test equipment grounded?
Perhaps you are a little inexperienced. There was a time when
virtually ALL test equipment came with a two wire (ungrounded) cord.
Then it was decided that having technicians electrocute themselves was
undesirable from both efficiency and moral viewpoints. As a result,
signal generators, oscilloscopes, frequency counters, alignment
generators, etc all were supplied with a 3-wire cord. Thus, when an
oscilloscope was hooked to a live chassis TV the probe ground burst
into flames rather than the technician falling to the floor in cardiac
arrest. Of course, there were those brave (or foolish) souls who cut
off the ground pin on the power cord to save a few dollars. While
others might disagree, I feel that using an isolation transformer is
preferable to losing my life.

PlainBill

On Mon, 14 Jun 2010 09:58:33 -0500 Chuck wrote in Message
id: :

On Sat, 12 Jun 2010 07:01:32 -0400, JW wrote:

On Fri, 11 Jun 2010 08:24:36 -0500 Chuck wrote in Message
id: :

On Thu, 10 Jun 2010 09:44:12 -0400, JW wrote:

Can anyone recommend a good isolation transformer for sale on-line?
Need one that will handle 5 amps or so at 120VAC, and have a standard AC
plug at the outlet. Prefer one for less than $100 or so, unless that seems
unreasonable. Found one at Mouser for $114 but that's only good for 1.25A.
Getting lots of irrelevant hits on google...

Thanks.


MCM Electronics has one. Chuck

Thanks Chuck. Looking at these for the moment:
http://www.mcmelectronics.com/produc...S500-/28-10160
http://www.mcmelectronics.com/produc...-1097-/72-1097

A bit more than I wanted to spend and a little less current capability,
but those may be the breaks.

Check out stock number 72-6670 isolation transformer $65.00. We've
had one for years and it works very well. Chuck

Looks like we have a winner.

Thanks again, Chuck. And thanks to all who contributed to the thread.