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Medical Grade Iso Transformer Mod - question (again)

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psap:
I have searched and read and watched on this topic but they all seem to be a little different and I am new at this. Could you please take a look at my annotated pic and let me know if I am doing this correctly?

The application is for safely testing vintage stereo amplifiers. I will also have a variac (soon) and will make the popular light bulb current limiter.
The device in question is another cheap surplus hospital grade iso transformer.

I have disconnected the coil secondary ground and all of the grounds to the outlets including the one to the outlet neutral (don't worry I will insulate all of those connectors). I have left the chassis ground from the incoming power cord. The outlets are still grounded to the chassis from their mechanical connection. So I still have continuity from the mains ground plug to the secondary outlet ground lug.

So, have I done all that I can do and now still need to use a 3-2 plug adapter for the DUT? If I understand all the lessons, you don't want the DUT ground the same as the mains - right? which this still is - yes?

Gregg:
Before you get too complacent thinking feeling safe about your personal safety as well as keeping your gear from letting out sparks and smoke; you need to really understand what an isolation transformer does and even more important, what it doesn’t do as well as how to wire everything appropriately.  You probably will get a lot of safety cautions on this forum.
A good and concise discussion is on the DigiKey website:
https://www.digikey.com/en/articles/the-basics-of-isolation-transformers-and-how-to-select-and-use-them
The wire you labeled ‘coil secondary ground’ is a Faraday shield that should be grounded to the ‘mains ground’.
The outlet ground wires may not be isolated from the outlet bracket that is bolted to the chassis; you can check with an ohm meter.  Isolated ground outlets are available and are commonly used in medical facilities where a totally separate grounding system is installed.  These often have a small green triangle on the face.  If you want the ground outlet port grounded it is advisable to connect the appropriate wires back to the ‘mains ground’. 
The wire you designated ‘neutral ground’ is probably the one you want to disconnect for total isolation of the power output.  Keep in mind that there will not be any distinction between line and neutral if this wire is removed.  Again fully understand what you are doing.

I would also suggest a two pole circuit breaker rated for somewhere near the max transformer rating on the power output; it is really handy to be able to easily switch the output with the transformer still powered.

Gregg:
I added text to a picture of my medical grade isolation transformer; you might find some of it useful.  I had to take out the stock receptacles and make an aluminum cover that fit inside to make it all work.  There isn't a lot of spare room inside.

psap:
I appreciate the help. allow me to feedback to ensure my understanding please.

1. reconnect the faraday shield to mains ground (the lug on the chassis).
2. Leave the "neutral to ground" connections disconnected as shown.
2. I did check the outlet ground with an ohm meter and they are grounded to the chassis. If I change the outlets to "isolated ground (orange) outlets", do I leave that ground lug unterminated? Isn't that the same result that I get in my pic by disconnecting the ground wires from the chassis? If they get wired back to mains ground then doesn't that defeat the purpose of the isolated ground outlet?

Again, thanks for the help.

psap:
just realized my mistake when I walked away. regarding my number 2 below now amended.

2. I did check the outlet ground with an ohm meter and they are grounded to the chassis. If I change the outlets to "isolated ground (orange) outlets", do I leave that ground lug unterminated?

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