3 phase

[patpete]

Hi all, could anyone advise me, I have a customer who has a 3 phase forklift battery charger running on 100amps. He now wants to tap off that suppy to run a 35amp cutting machine(415v). Can I tap off the knockout switch to run both machines? they are on 6mm cable. thanks, patpete.

 

[supasparxs]

If it were me. I would put a 3 phase board in. And then put a supply to the battery charger and then one to the cutter (isolators in place)

 

[Knobhead]

You really do need to install a DB. This sounds like a typical workshop, cobbled together over the years. At some point something has to be done to sort them out. I hope you have the gift of the gab to persuade them for their own sake. But I’ll bet you they’re tighter than a ducks bum!

 

[patpete]

If it were me. I would put a 3 phase board in. And then put a supply to the battery charger and then one to the cutter (isolators in place)

Yeah, exactly what I wanted to do, but they are, quoted byanother forum member “tighter than a ducks arse”. Thanks for your responsematey.

 

[patpete]

What can I say, you have hit the nail on the head, you have been in this game for some time! thanks for responding. Patpete

 

[Inteificio]

I work in a place where bodging is normal, did I say that, I meant working efficiently is normal ;-)

If the original cable has enough capacity and has been rated correctly then just stick a spur off it without reducing cable size, so if original is 6mm then stay 6mm.

If the 'fuse' keeps tripping, then the original circuit needs modifying, don't let him up the fuse.

I quite frequently do the above, if the CB is rated to protect the wire then the wire is safe, keep sticking more load on until the CB tells you it is too much.

 

[supasparxs]

Yeah, exactly what I wanted to do, but they are, quoted byanother forum member “tighter than a ducks arse”. Thanks for your responsematey.

If I were you I would give a quote to carry-out the work how you feel how it should be done.
If you are challenged about you can defend the design.
If the customer wishes to go with someone else's design, it is upto them.
However if the other design is flawed, it is not your concern. You are not responsible for anyone else's work.

If the customer challenges you and wishes you to match the price, and the design.
you will be able to pull apart the proposed installation.

Sometimes it's better to walk away, rather than leave yourself open to problems in the future

good luck

 

[dingledong]

yes cos once youve done it your at there beck and call for the rest of your life with no charge because" you fitted it "

 

[supasparxs]

yes cos once youve done it your at there beck and call for the rest of your life with no charge because" you fitted it "

Hi Dingledong,
maybe you should read the whole thread again, and check who said what.....

 

[UNG]

Sometimes it's better to walk away, rather than leave yourself open to problems in the future

Walked away a lot of times only to be called to fix the problems left by others, If things go pear shaped and I get called back to sort it I usually add 10% to my original quote for covering undoing the bodges

I find engineering shops are usually the main culprits of wanting the bodgit installation, a quick fix so they can get that important job out

 

[supasparxs]

In that case, you should point this out to the customer, so next time they will actually go with your quote in the first instance

 

[UNG]

In that case, you should point this out to the customer, so next time they will actually go with your quote in the first instance

Have had customers call me asking me to match the cheapest quote they have because they want me to do the work as they know the quality of my work so I end up explaining why I am more expensive but it does not always work

 

[graham4]

could anyone tell me whats required to make a 3phase sunbed safely operate in a domestic home,im not a leccy but will be using 1 to install,many thanks

 

[malcolmsanford]

Graham the reason it is 3 phase is because of the power it can draw and I doubt very much a domestic home will have enough to run it via a phase invertor.

A 200 watt lamp uses roughly 1 amp of power and some of these beds can have 40+ lamps and these are smallish ones, you can go much bigger than this. Also these loads are inductive and therefore have a start up over current of roughly 10-20% of the Full run load (FLA)

 

[graham4]

thanks,will have to sell it on then,very good of you to take the time to reply

 

[Knobhead]

The sun bed could be made to run on single phase. It would require a fair amount of rewiring and a hefty supply.

PS you really should have started a new thread for this.

View attachment 8903

 

[Inteificio]

You can get 3 phase inverters that will produce 3 phases from a single supply; or you could get a sparky to convert it to single phase (get one who works with machines, most house bash only will probably get confused).

What is the power use of this device and what is the rating of the BIG incoming fuse next to your meter (probably 80 or 100a).

You could get it to work, but really the most important issue is that you want a sun bed in your home?!

Seriously how much do you hate your skin?