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May 31, 2020, 06:34:11 AM

Author Topic: Isolation transformer advice  (Read 171 times)

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Offline Neuronal

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Isolation transformer advice
« on: April 02, 2020, 10:38:33 AM »
I'm a near-total newbie, and in reading the intro material to my kit it recommends an isolation transformer for safety. From reading online, the standard Tripp-Lite isolation transformers are used for de-noising, but don't actually provide safety if you are working on your rig hooked up to power. Is that right? Can I use something like this instead? - https://www.jameco.com/z/ITR300-Power-Transformer-Isolation-120VAC-120VAC-300VA_181315.html

thanks so much in advance for advice, and my apologies if this answer is obvious.
Bob Datta

Offline Paul Birkeland

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Re: Isolation transformer advice
« Reply #1 on: April 02, 2020, 12:29:31 PM »
I'm a near-total newbie, and in reading the intro material to my kit it recommends an isolation transformer for safety.
You'll be OK without one.  That recommendation really comes from the time before we used power entry modules with integrated fuse holders.  Now that we do, you'll blow the fuse before you get much more than a rigorous tingle if you touch the mains.  If you happen to have a GFCI outlet, it will trip at about the same time that you realize you've touched the mains.  That's what I would recommend using for wherever you're building the kit.  You can get a plug in GFCI for convenience if you don't want to replace an outlet or don't otherwise have one handy. 

Paul "PB" Birkeland

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Online Thermioniclife

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Re: Isolation transformer advice
« Reply #2 on: April 02, 2020, 01:12:58 PM »
Hello,
I use a Tripp Lite isolation trans my self and can tell you that it is not truly isolated in the fact that on the secondary side the neutral is also connected to the chassis. This is however easily corrected by opening up the unit and you will see that on one side the white neutral wire has a green wire spliced to it and is connected to a chassis ground stud. simply remove the green wire from that stud and insulate it with heat shrink and now you will be fully isolated from ground on the output.
This helps keep the sphincter pucker factor down when working on sketchy equipment.
Lee R.