cable size

[betty swollocks]

hey lads its been a long time, since i was an apprentice, since i did 3phase so can someone help me out with cable size and 3p mcb required

all i know is the machine is a bench saw rated at max 45A total not per phase

cable length is going to be @25m

if memory serves ive calculated max demand will be @27kw

and with p.f of 0.9 gives a rating of 13.5A per phase

does this sound right?

as the run in to be in box trunking i was going to use sy 5 core because of the drop from the box trunking down to the isolator

have i missed anything or am i right? wrong? close? lol...

thanks in advance lads

 

[Evans Electric]

Betty , do you know the HP of the motor ? I would take a guess at using 2.5 mm SY or SWA with a 20amp Type C breaker or 25amp fuses or 16/25M fuses .

Deke

 

[Andy™]

Betty , do you know the HP of the motor ? I would take a guess at using 2.5 mm SY or SWA with a 20amp Type C breaker or 25amp fuses or 16/25M fuses . Deke

that sounds about right. maybe use 4mm though incase of VD problems (cant be bothered to work it out)

 

[Lee321]

10a/ph is a very powerful machine. i doubt a bench saw is a 1/4 of that

 

[green-hornet]

If the machine is rated at 45 amps total and the max demand is 27kw this would give you around 14amp per phase, this must be a big machine!

Most I have seen are wired in 4mm with 20 amp fuses, or 6mm with 25amp fuses but they demand a lot more than 14amp per phase.

 

[Andy™]

maybe the 47A includes start up current, but once running will use much less?

 

[Apache]

The biggest table saw in Axminster costs

 

[Lee321]

The biggest table saw in Axminster costs

 

[betty swollocks]

thanks lads as ive said all i know is what ive been told, machines being delivered on wednesday next week and the info has come from the buyer, im going to see him saturday morning to see the spec for myself, just was hoping to put some costs together, its been awhile since my last commercial job so i wouldnt know how BIG a big saw would be lol

 

[Andy™]

The biggest table saw in Axminster costs

 

[Lee321]

it should have a starter control attached too so check for that otherwise you might have to supply that too as ALL 3ph motors need overload protection other than the supply mcb unless its a combined motor mcb/overload which is unlikely unless being supplied from an control panel rather than a distribution board

 

[Lee321]

surely im not the only one to think this has something to do with Admins shed?

lol a budding british version of bob vila is he andy?