16A supply

[Robotstar5]

I would challenge your fluke. On a 2.2kw which us 3hp the start load is 19amps.

A clamp meter is not a reliable measurement of starting current.

 

[tlovatt]

For a 2.2kw motor the running current should be just under 10A and so starting under load the startup current will be between 3 and 6 times this figure for a short period of time, so 55A is the right sort of ballpark, but only for a brief period of time.

I have a few 2.2kw motors that start from a 13A plug without blowing the fuse - probably better built motors.

If the compressor blows 13A fuses then add a 16A socket to the exsting circuit for now, but be aware that with other things switched on you may trip the breaker on motor startup.

 

[robinj66]

Thanks, I will try that.

 

[brightspark]

I would challenge your fluke. On a 2.2kw which us 3hp the start load is 19amps.

A clamp meter is not a reliable measurement of starting current.

i dont know where u get your measurments from as a 1.5kw motor pulls 30 amps on start up

 

[Mr shiney]

i dont know where u get your measurments from as a 1.5kw motor pulls 30 amps on start up

From the Instruction manual that came with my 2.2kw Hydrovane compressor. It gives the starting load as 19amps and the running load as 10amps.

I will stick my Fluke on it in the morning out of curiosity and see what it says......

 

[printcom]

I always thought that the start up load had a lot to do with start up current, I am not sure if these compressors have an un-loader valve or do they start fighting against the residual pressure left in the tank? Maybe that's why we always assume a variance of between 3 and 6 times running current.
All I know for sure is that my SE16C150 will trip a 16A mcb 70% of the time and a 20A B type mcb occasionally.
I've also got a fairly new single phase 3hp wood bandsaw and that also requires a 20A mcb.

 

[Mr shiney]

Stuck the fluke on my Hydrovane this morning for a bit of mischief. I got 26amps on the start compared to the book figure of 19amps and I got a full load running 11.4amps.

Now either the fluke is not fast enough to catch the initial spike mentioned here or they have damn good softened starter.

 

[tlovatt]

The hydrovane probably provides a lower starting resistance (force) to the motor compared with a standard pison type compressor which will make a big difference to starting current

 

[Daz1968]

We have a se16c200 on a 16amp type c breaker at work and it works fine never tripped it at all and wired in with 4mm cable. Mine at home is on a 30amp type b also on 4mm cable and is fine, think that clarke state minimum 30amp supply.

 

[tlovatt]

A 32A breaker for a 2.2kw motor is too big, you should look to have the size and type of breaker that will allow the device to relaiably start with the smallest breaker possible

 

[brightspark]

take it from me the meter will be correct. if it wasnt fast enough it would give a low reading not a high one . the only thing they wont do is give a reading on turning on a 11ov . 2,5kw transformer or the inrush on my 180 amp welding transformer which take out a 30 amp b type breaker on just plugging in