Hi, I need to supply a PIC for a project and the only source I have is a 400V RMS. I heard that there are current sensors that can supply the PIC.

Anyone knows any of this current sensors?

Also what would be the best way, both economical and smalest to supply the PIC with 400V RMS.

Thank you for your patience,

Regards,

Miguel

 

You said 400VRMS so this is AC. The only safe way is with a step down transformer feeding a +5V regulated supply circuit.

 

Hi, thank u for your prompt answer.
In fact at 1st we think on that solution but it is too big for what we are developing. We want an efficient but also small solution. A Ac-dc supplie would be a good choice but we cant find any for 400v ac. Our teacher sayd also that there are some current sensores that can supplie the pic but we cant find them. Again thank u for your answer.

Regards


Miguel

 

There are other ways of doing it but none that I'd dare post. This is mainly because of safety concerns. 400VRMS is LETHAL, so I wouldn't post anything without an isolation transformer included.

 

Hum where could i find a small and cheapest
Transformer with such redution factor.

Thks again for Ur aswerr

 

Is the teacher suggesting that a hall sensor be used as an isolation transformer? It could work, but would require a somewhat predictable, steady load on the 400v line so that current was flowing.

 

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en011202

Look at page 3. I have built this before with 120VAC but 400V/230V may be excessive. (I am assuming that the 400V is 3 phase L-L but 230 L-N may be do-able). Call pic, they are helpful and could probably tell you if that would work.

 

http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en011202

Look at page 3. I have built this before with 120VAC but 400V/230V may be excessive. (I am assuming that the 400V is 3 phase L-L but 230 L-N may be do-able). Call pic, they are helpful and could probably tell you if that would work.

Never mind that post.....not what you are looking to do after I read through again. That was zero crossing detection that I used that for, not powering. My bad.