Understanding Isolation XMFR
Understanding Isolation XMFR
(OP)
Does anyone know of a good document explaining how an isolation transformer *works*? That is to say: I'm wanting to know the fundemental distinct differences between a normal transformer and an isolation transformer. I'm having trouble finding such info by searching online.
Many Thanks,
Sense
Many Thanks,
Sense






RE: Understanding Isolation XMFR
Do a Google search on "shielded isolation transformers" and you'll get a bunch of hits.
Here's a starter:
http:/
RE: Understanding Isolation XMFR
RE: Understanding Isolation XMFR
Eng-Tips: Help for your job, not for your homework Read FAQ731-376
RE: Understanding Isolation XMFR
An application for an isolation transformer may be for code compliance. One example would be Life Safety such as hospital circuits.
Compliance with CSA preliminary Standard Z32.1-M1986, Clause 5.4 Which mandates an electrostatic shield when the primary voltage of an isolating transformer exceedes 300 Volts.
Specifications or codes may call for ungrounded circuits over combustible fibres to limit fire hazard. This application may possibly be satisfied with an off-the-shelf dry type transformer. Possibly a 240/480 primary 120/240 secondary.
Drives may require isolation transformers with special characteristics.
We're all saying the same thiong in different words, senslessticker. And to repeat again let us know your application.
yours
RE: Understanding Isolation XMFR
If somebody wants you to install a 120 volt underwater light that has the bulb underwater run away from the job - what the CUSStomer has is a piece of dinosaur dung that they bought at a closeout sale. There are a lot of business people who cannot resist and alledged bargain not to mention that 1/2 of real estate snots are moronic enough to put up drywall before calling an electrician. I just simply refuse to do business with cheapskates and morons.
RE: Understanding Isolation XMFR
The current application is this:
Quoting from the electrical requirements for a specific room of a new building: "3 isolated 120V circuits for sensitive instrumentation". The programming manual for this new building refers many times to "isolated 120 V circuits for instrumentation".
In the past I've seen seperate "instrument ground" grids installed throughout a facility, and also "clean power" panels that are fed from 480/208 Wye "isolation" transformers. I suppose the real issue is the context by which someone uses the term "isolation". I understand the grounding differences. But it appears the term "isolation" can have many different electrical interpretations. Is this correct?
RE: Understanding Isolation XMFR
RE: Understanding Isolation XMFR
I would be rechecking the specs for any special requirements.
As I understand your post, the requirement could be filled with 3 "Off the shelf" 1500VA, dry type lighting transformers.
Depending again on the spec. you may be able to use an isolated panel, in whitch the circuits are isolated from the main power system, but not from each other. Then it would be one transformer for the whole panel.
yours
RE: Understanding Isolation XMFR
However, it could also just mean the 3 circuits are to be dedicated to the instrumentation equipment only.
Maybe you can get whoever wrote the specification to clarify the requirement.