Transformer Query 3

[grapesrus]

We are installing a small water treatment plant and contracted to have 220v single phase power supplied to the site. the contractor installed two wires(850'in length) to the panel with a ground rod connection to the breaker panel. He stated that he would install a transformer for any 110v requirements we had. The control panel (a duplex type for 2 220v single phase pumps which pulls power from one leg for the 110v analyzers, samplers etc.) requires a neutral for the 110v equipment. The electrician is now telling me that a transformer will not give me the neutral I need. I contacted the panel builder and one solution is to replace the 220v starters with higher amp 110v units. My basic question is; can I come up with the neutral I need without repulling the line wires & adding a neutral($3K) or purchasing new starters? Thanks for any advice.

 

[waross]

You should change electricians. Other than that, change electricians. Possibly try a well trained third year apprentice. Simple installation, simpler electrician.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[rbulsara]

Someone is pulling your leg or you need to hire different electrician and panel builder.

Your control supply needs 110V between two supply wires, one of them does not have be a neutral per se. Any 220V:110V control transformer will have two terminals on the secondary side with 110V between them. Either one of them can be assigned as "neutral" if you want to call that.

 

[itsmoked]

You then bond the assigned neutral to ground.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[grapesrus]

Thanks to all for helping me out. I will find a new electrician and have him install the transformer. One last question if you have a moment. Are there any manufacturers you would recommend for the transformer. I want the best. Thanks again.

 

[rbulsara]

Any one of the usual suspects, GE, Square D, Eaton, Siemens, etc. are good. You need to specify correct rating (VA). Look up control transformers in their catalogs.

 

[itsmoked]

Pretty much any "control" transformer should work fine.

I have used these with great success:

http://www.factorymation.com/s.nl;j...e3eSc38TaNqNe34Pa38Ta38Sax10?sc=2&category=97

Beware you generally need fuses on both sides. Some of these will have nice holders mounted on them.

Keith Cress
kcress -

http://www.flaminsystems.com