Large single phase motor question.

[squib]

Hello all, I want to upgrade my planer to a 16" model but 3 phase is to expensive to plumb in, and a convertor seems rather expensive for this size so my question is will a 4hp single phase motor be suitable to replace the 4hp 3 phase one already on the machine or are modern motors not up to it. The motor i am looking to buy is this one.....
http://cgi.ebay.co.uk/Electric-Motor-Si ... 4151a57f9e
Thanks Squib.

 

[JonnyD]

Ive got a sedwick 12inch planer in single phase which has a 4hp motor and it can cope easily with full width cuts so would probably be able to handle the extra width the motor is a decent brook crompton one. My other planer is a griggio 17inch wide planer and that has a 4hp 3 phase motor on it and that handles wide boards pretty easily.

A 5hp one may be better in single phase but will be a few quid more.

Is the 3 phase one a single motor machine because if it has a separate geared motor for the feed it may become a lot more money to change 2 motors and switch gear?

cheers

jon

 

[yan]

Hi Jonny D,
4hp is 4hp whether single or 3phase.
Only problem is starting and running current being a lot higher with single phase.

 

[ProShop]

I'd put in a 5hp if you can.
4hp single phase hasn't the torque grunt of 4hp 3phase.

In theory it should be the same, but in the real world it's not.

 

[squib]

Thanks for the replies, i have sourced a 5hp for around £200 delivered which seems ok so just need to find a good planer now, oh and a big starter switch!

 

[tjwoodms]

shouldnt be to much of a problem but you may need to fit a new contactor and thermal overload as well as a slight mod to the motor feed.
Your contactor basicly needs a 230v coil and you may find the one fitted has a 415 v coil. Its easy to check it should be printed on the contactor.
If it isnt a 415v coil will have a link from L1 to A1 and L3 to A2 and a 230v coil will have a link from L1 to A1 and no link from L3

 

[tjwoodms]

sorry i forgot to mention
you need to make sure you get the correct frame size or it wont fit as well as is it flange or foot mounted

If its foot mounted its not such and issue as you can usually modify the machine but if its flange mount its not so easy

Also you need to make sure you get the correct shaft size or you will have to shell out for a pully as well

 

[Digit]

Also you need to make sure you get the correct shaft size or you will have to shell out for a pully as well

Plus a bloody hefty cable! :lol:

Roy.

 

[yan]

I think a 240v to 3 phase convertor would possibly be around £250 to £300, providing your existing motor is dual voltage which they normally are.
Should say on the rating plate.
This would also give you the option of soft start, variable speed and braking.
Something else to think about.

 

[simplypowersupply]

I think a 240v to 3 phase convertor would possibly be around £250 to £300, providing your existing motor is dual voltage which they normally are.
Should say on the rating plate.
This would also give you the option of soft start, variable speed and braking.
Something else to think about.

I know quite a bit about Single to Three phase converters and the first thing to say is that you have to be very careful in sizing them and ensuring you have a balanced load.

The other thing is that there are two types of these converter - Static ones ( Static Converters ) and Rotary ones ( Rotary ).

In order to protect your motor it is always best to use a rotary unit, these work by taking a three phase motor, then using the single phase to wire to two of the terminals and then the third pahse is generated by the motor windings. If you use a typical static unit you can end up submitting the windings of the motor/s in your machine to too many amps and too often.

Hope this helps and feel free to visit our site and get in touch if you need more advice

 

[simplypowersupply]

Mods

Sorry if I was breaking rules by adding URLs, however I was genuinely trying to help!

 

[tisdai]

Hi simplypowersupply

The reason for the ****REPORT TO MODERATOR** where you placed the link is to stop spam bots from posting links, once you have reached the 10 post mark you will be able to post links,, the same happened to me when i 1st started on the forum.

So you have not broken any rules as such

Cheers

Dave

 

[simplypowersupply]

Dave

Thanks for the reply - I thought I was in trouble!

Cheers

Simply

 

[Woody Alan]

Simply,

Thanks for the info, your static converter link contains an extra http://

Cheers Alan