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isolation transformer!!! i need help

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mkarimshah

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i am working on my FYP which is related to power line. i need to use an isolation transformer in my project and i was searching about the frequency and other ratings of it but could not find any thing on the net. can any one help me that is ther any ratings of isolation transformer????

Added after 1 hours 4 minutes:

the power line here in pakistan are operating at 60hz and i want to send data on the power line which is in khz range and i want to know is there any limitation of frequency on isolation transformer??? or a transformer which works fine for 60hz will serve my purpose.
any help will be apperiated...thanks
 

to "send data on the power line", you'll need some kind of coupler, at least a capacitor that blocks main frequency voltage or a higher order highpass. If isolation is a requirement, it would be more economic to use a mid/high frequency transformer and the coupler between mains voltage and transformer- It can be much smaller than a transformer designed for 50/60 Hz and hasn't the high leakage inductance of a mains transformer, that actually limits it's capability to work at higher frequencies.

If it's a standard power line communication application, you should refer to known working designs for the respective standard.
 

@hameed......thanks for the correction

Added after 8 minutes:

@Fvm...
i need to isolate the device(which will be a kind of modem) from the power line and for that i have two option , optocoupler and isolation transformer. and i want to go for isolation transformer.
i searched for isolation transformer and most of them are designed for 50 or 60 Hz but i need to send high frequency signal(in kHZ) along with the 60Hz power signal.
so will the 60 Hz isolation transformer work for this multi frequency signal??
my actual project is to develop the modem so i want to purchase the available product wich can serve my purpose for the isolation.
 

I siad what's the advantage of a specially dimnesioned midfrequency transformer. The other point is the most likely much lower signal voltage, so the transformer can use e.g. an E16 or E20 core.

A 50/60 Hz transformer can work depending on your application parameters. As said, leakage inductance can be a problem. To get an idea about the order of magnitude, simply assume that at least half of the transformers voltage drop in nominal operation is caused by series respectively leakage inductance. Depending on your operation frequency, the inductive impedance will be considerable.

You can do some rough calculations to get an idea of the effect.
 

Picture below shows how isolation can be realised in Power Line Communication Systems and here are typical coupling transformers used in Power Line Communication:

**broken link removed**

Rgds,
IanP
 

Yes, there are two options:

- Transformer as above from IanP.
- Kind of optocoupler like HCPL-800J. Then you don't need transformer anymore.

Cheers
 

@ IanP
Picture below shows how isolation can be realised in Power Line Communication Systems and here are typical coupling transformers used in Power Line Communication:

**broken link removed**
Impressive nice doc
 

@lanP

the attachnment u hav made is not opening.
if u hav the data pls mail me.
 

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