Isolation Transformer - Page 1
Forum section: electronics / projects

author: raptor1956
author_rank: Frequent Contributor
timestamp: September 06, 2016, 10:25:13 pm
content: So I've been thinking about getting an isolation transformer for some test work and I started looking at some toroidal transformers that might do the job. There's one that's right about the power/current level I'm looking at but the description seems a little vague and I wonder if someone can comment about it. See link for the transformer for reference...https://www.amazon.com/HAMMOND-1182P60-TRANSFORMER-TOROID-625VA/dp/B011P0VG6K/ref=sr_1_4?ie=UTF8&qid=1473199255&sr=8-4&keywords=toroid+transformerThe description doesn't explicitly state whether or not it's a 1:1 transformer with the output voltage equal to the input and say's only that its 120V, 625VA, and that the secondary voltages is 2 x 60V. So, from this I presume it has two secondaries so that you could have two seperate circuits of 60V or that you could tie them together to make one circuit of 120V -- is that correct? Sadly there appears to be no reference to the input voltage so there's no way I can see to determine if it's a 120VAC or 240VAV primary though my guess is a 120VAC primary. And finally, although it seems unlikely the outputs would be tied to the inputs via ground and therefore non-isolated they have not explicitly stated this.So, if this is indeed an isolated transformer that can be wired to output 120VAC from a 120VAC input it would be a potential component in an isolated transformer for test purposes. I'd need to build a box for it and add a switch and circuit breaker as a minimum but the power rating is sufficient for my needs.Brian

author: DaJMasta
author_rank: Super Contributor
timestamp: September 06, 2016, 10:50:35 pm
content: A quick google shows the datasheet for the part, even though amazon doesn't list the specs - if the part number is accurate, this should answer (at least some of) your questions:www.hammondmfg.com/pdf2/1182P60.pdf

author: MagicSmoker
author_rank: Super Contributor
timestamp: September 06, 2016, 11:04:14 pm
content: What you really want is this:https://smile.amazon.com/Variac-Variable-Transformer-Isolation-1000va/dp/B006NGC6HU/ref=sr_1_8?ie=UTF8&qid=1473202871&sr=8-8&keywords=isolation+transformer

author: raptor1956
author_rank: Frequent Contributor
timestamp: September 07, 2016, 12:32:01 am
content: Quote from: DaJMasta on September 06, 2016, 10:50:35 pmGreat, thanks for finding this...OK, so it looks like to get 120VAC in and 120VAC out I'd want to tie the two primary windings together (BLK with BRN and WHT with ORN) then for the secondary tie them together (BLU with GRY).Brian

author: raptor1956
author_rank: Frequent Contributor
timestamp: September 07, 2016, 12:36:41 am
content: Quote from: MagicSmoker on September 06, 2016, 11:04:14 pmYes, that is another option, but the comments on Amazon suggest quality issues...Brian

author: floobydust
author_rank: Super Contributor
timestamp: September 07, 2016, 01:33:55 am
content: I find some transformers are spec'd to be 1:1 at full load, so extra turns on the secondary windings to compensate for losses.

author: raptor1956
author_rank: Frequent Contributor
timestamp: September 07, 2016, 01:48:54 am
content: Quote from: floobydust on September 07, 2016, 01:33:55 amYes, seen that as well. Saw one listed as 120VAC:123VACBrian