3 phase options

[gman1001]

:idea:
Hi guys,
I was wondering if anyone would be able to advise me on my 3 phase options for a recently purchased Felder K700s ? This is my position ,I have set up a temporary workshop on site of a large development that will be a years work they have a large generator on site that has a 415v output I am able to use but it is 40 meters away from workshop ,also we have 240v in the workshop with approx 50amp .I have a budget of upto £1000 but would like to obviously spend as little as poss.My electric skills are not good at all and will use a electrician to carry out works.The machine is 5.5KW 50HZ V400 with no scoring blade ,If I list my options it would be great to hear on your opinion or even advances on a better idea.
(1) Purchase a 40 meter 6mm 5 core armoured extension
(2) Purchase a transwave 7.5 kw rotary converter ( plus side being if i move on to another workshop with 240v)
(3) purchase a digital converter ( but i am lead to believe is wired different)
Currently I dont have or intend to run any other machines at 3 phase .

Your advice would be really really appreciated thanks

Glen

 

[nathandavies]

I am currently using a generator for my 3 phase, I have a transwave rotary convertor ready to be installed. for you I think I would go with the extension cable run in ducting underground. I think it would just be easier.

 

[CHJ]

My first thoughts are buy the cable, cost it into current contract let it earn its keep on current job. Simplest of solutions.

Buying convertors of any description, there is no guarantee that future sites will have a single phase supply capable of driving them and you have to do a fair bit of research to guarantee they will be matched to machine start and run loads and capable of driving it.

 

[gman1001]

Thanks for your opinions much appreciated
Buying a cable seems to be the most instant,cheapest and hassle free soloution .If I purchased armoured will I need to bury underground ? (its on a hill and 50m trench will probably cost me £ 500 in labour),Do you guys know what type of cable etc or the best place to purchase?

 

[nathandavies]

you don't have to bury armoured if you don't want to but if it's a year it may well be worth it, depending on vehicles and people travelling over it. get your electrician to find it for you, he should have good terms with a supplier. over spec it if you are unsure as to size.

 

[MMUK]

Personally I would over spec the cable to 10mm to allow for any surges. Also don't forget there will be a voltage drop over such a long run that you may need to compensate for.

50m of 10mm SWA LSF 3p+N+E (5 core) will cost you around £300
50m of 10mm SWA LSF 3p+E (4 core) will cost you around £200

I tend to buy smaller quantities of armoured from here: http://quickbit.co.uk

 

[CHJ]

Will the ground that cable has to cross be subject to traffic, foot or site machines?

 

[gman1001]

Thanks chaps ,
There will be light pedestrian traffic, excuse my knowledge of electrics is there any advantages of 5 core over 4 core?

 

[MMUK]

Thanks chaps ,
There will be light pedestrian traffic, excuse my knowledge of electrics is there any advantages of 5 core over 4 core?

Which one you need will depend upon how the machinery is wired. You need to find out by either looking in the manual or directly in the junction box on the machine itself to see if there is a Neutral connection along with the 3 phases and earth or not. It will also depend on how the generator output is wired.

 

[gman1001]

Ok think I best get the electrician to take that bit on !!!
Massive thanks for all your help guys I was very close to buying the rotary converter so it was great to get your thoughts on this and also save some money .

Thanks chaps