Power problems

[Rettie86]

Hi Guys,
I am new here and a little bit of a novice and seeking some professional help.

I own an industrial unit that was used in the past by the MOD. The problem is that when i use a pressure washer (240v 2000w) it won't start up, instead it makes a buzzing sound until the thermal cut-out switch kicks in. Also when trying to start the pressure washer you will notice the lights dim a bit as if the pressure washer was trying to drian all the power. The unit has what looks to me "up to date" electrics as at some point in the last year it has had more power outputs lined around the walls. If i was to use another power tool or electrical appliance it would work fine. The trouble shooting guide says if it buzzes that it is either the motor has seized (checked and turns fine) or there is a low line voltage problem and if someone could help me out i would be very greatful

Thanks,
Rettie

 

[Spudmiester]

Could be anything anywhere along the line. Have you gt three phase or just single.
Have you tried it in another socket ?

 

[old dog]

sounds like the power washer is the problem seized try the power washer maybe in a
n other location ie unit next door if they would let you
my money is on the power washer

 

[Carter]

If you're using it outside how long and what size is that extension lead.
If you've joined a couple together then you could expect serious volt drop through the cable length and/or iffy socket connections. you could measure the voltage at the socket and again at the far end where the washer is plugged in and compare the two. With the machine switched off (no current flowing) the two readings will be the same.
Now you need to turn on the machine and check the voltage reading at the jet washer end whilst under load. Now that current is trying to flow the volt drop (if any) will manifest itself. Compare the two and get back to us.

Alternatively, (and safer if you aren't sure about measuring live circuits) plug directly into a socket (no extension leads) does it still fail to run or symptoms less severe?

 

[jascfc]

Are you sure the water is turned on? As I know someone else who had a similar problem and found that there was a blockage stopping the water getting through and this caused a buzzing noise....

 

[London Luke]

check that water is coming out from the nozzel without power

 

[Rettie86]

Hi guys, Thanks for the feed back.

The pressure washer is brand new and hasn't been used properly (with working pressure).

There is no blockage and water does come through (even when switched off), also the motor can turn by hand so it is not seized. I haven't used an extension cord yet so i can rule that out.

Last night i had a look at the fusebox/breaker panel and noticed it has 3 Phase but the socket are single phase but the live for the socket connects to the L1 of the 3 phase and the neutral of the single phase (sockets) is connected to the neutral of the 3 phase

Edit: I have also tried every socket, they all have the same problem

 

[wayne]

a single phase motor not turning. could be acapacitor problem ie not split phasing

 

[Rettie86]

I noticed that you can wire up the single phase to L1 and the system neutral or both live & neutral (single phase) to L1 and L2. Would changing the neutral from the system neutral over to the second one L2 (using both phases rather than system neutral) make any difference or does both wiring methods have the same results.

 

[montybaber]

I dont really understand what your saying but do you mean move the neutral feeding the single phase ring to l2 then you will get 415v line-neutral and the pressure washer will do more than buzz.

Do I understand correctly....if so please dont play!!!

sounds like the pressure washer to me, as mentioned possibly capacitor

Double check the details on washer and post it up

 

[tony.towa]

Thie going to sound like a series of daft questions but there is method in the madness.

What colour is the plug that you have on the washer?
How many pins does it have?
What pins are the core cables of the washer connected into in the plug? (i.e. brown to L1 etc)

 

[jibspark]

i would try it at another location (another unit or at home etc) as mentioned earlier, at least if you do this you might be able to see if if its the washer or the circuit.

 

[Rettie86]

cheers guys,
I am going out to the unit tonight, i will get pics of the fusebox showing where the wires are connected, i will aslo get the pics of the spec for the washer. I will be bringing the washer home tonight to test at home, so i will give a lil update soon.

Oh my god, it doesn't get any better. I brought the pressure washer home and plumbed it in and switched it on and i got the same result as using it at the unit (the buzz).

All it says about the power input on the box is: 230v-240v~50Hz 2000w. I think it will be a trip back to the shop.

 

[rumrunner]

dont worry about it,check the pressure switch is making ,leave it turned on for a bit and as the pressure builds up it should be ok ,most pressure washers buzz,if it burns out get another and claim extra for inconvenience
good luck

 

[Rettie86]

No matter how long i leave it on, it will never build up pressure what so ever. it will only buzz for about just over a min until it gets too hot then the thermal cut-out switch kicks in till it cools down. What annoys me is that it is brand new and SHOULD work first time.