Proper Isolation Transformer Units (PITU) - Page 1
Forum section: electronics / projects

author: salihkanber
author_rank: Regular Contributor
timestamp: June 17, 2023, 02:00:49 am
content: There are 3 Isolation transformers in our lab, one with 1 x 1KVA rating with 2 x 500VA outputs and it stands in a DIY-like case on the floor. Another 2 x 150VA ones was located also in a DIY style in-front and right above our desk like this;Then I realised that we could design and build Proper Isolation Transformer Units (PITU I call them) for everyone and started this journey by building first 2 for ourselves with the 2 x 150VA's inside;Here is the image from the first design;The two will have these specs;1 x 150VA capacity 220VAC/220VAC isolated Type C output plug with lidIEC C13 Power Input PlugON/OFF Switch with power lightChangeable fuse at the backGround connections in front and at the backGhost handleEarthed sheet metal casing with yellow-black colorAny feedback will be appreciated, thanks.

author: salihkanber
author_rank: Regular Contributor
timestamp: June 19, 2023, 01:51:30 pm
content: Ok here we got some metals, what am I supposed to to with them?!

author: Terry Bites
author_rank: Super Contributor
timestamp: June 19, 2023, 03:23:38 pm
content: Er, bolt the transformers inside and screw the covers on??You want to protect your costly iron parts. Install a fuse holder. A switched and iec inlet . A MOV or two across the inputPut a crimp eye on the earth lead and bolt it onto the steel box with a star washer under it.Maybe cut a hole to suit a shuko outlet?What does proper mean?It will properly kill you just as well ar regular mains outlet.What leakage currents will you get using thse xfmrs, will that work for your lab scenarios?For the lab you want a transformer with very high insulation resistance and low interwinding capacitance.An interwinding shield helps with that and reduces the coupling of common mode noise from input to output.A split bobbin type is usually a better choice than a layer wound one.

author: salihkanber
author_rank: Regular Contributor
timestamp: June 19, 2023, 07:42:59 pm
content: Quote from: Terry Bites on June 19, 2023, 03:23:38 pmThank you Terry, All will be installed.Quote from: Terry Bites on June 19, 2023, 03:23:38 pmI couldnt find a proper, an-equipment-for-lab-shaped isolation transformer unit with my requirements, thats why the name. No intention of killing or harming anyone, and please dont let anyone do that on the image, esp with 150VA it wont work tooQuote from: Terry Bites on June 19, 2023, 03:23:38 pmAre you mentioning the efficiency loss at this point?Quote from: Terry Bites on June 19, 2023, 03:23:38 pmCould you please explain the effects of low insulation resistance and high interwinding capacitance?Quote from: Terry Bites on June 19, 2023, 03:23:38 pmGot itAnd please tell me whether you can find that kind of an isolation transformer unit in the market at a good price range? What do you use in your lab?

author: salihkanber
author_rank: Regular Contributor
timestamp: July 12, 2023, 09:30:13 am
content: Metals have been painted and installation of the main components has been initiated.

author: salihkanber
author_rank: Regular Contributor
timestamp: August 19, 2023, 08:37:52 am
content: Here come the stickers of the front & back panels.. Wait.. What the!..