Help Needed - Electrical symbols inside a pump

waddo


Joined: 29/11/2008
Posts: 1966

Message Posted:
17/03/2010 19:05

Just bought a new pump and a presscontrol - It all works (kind of) but not sure if I have the electrical connections correct.



Connections inside the presscontrol are L1 (I take that as live supply in), N (I take that as neutral in) and earth.

Connections for output to the pump inside the presscontrol are earth (got that sorted now), U (no clue there and V (now lost altogether).



Questions are - What the hell is U? What the hell is V? Logically, one must be Live and one must be Neutral - but which is which?

proger1



Joined: 18/04/2009
Posts: 2919

Message Posted:
17/03/2010 19:24

On an AC system you have U,V and W for the three phases but if there is only U and V it is not a set up I am used to seeing.

I have asked someone who is more electrically biased and he says that there is the possibility that because there is only U and V it is probably possible to use either as your live from the presscontrol and then check the pump rotation, if it rotates in the wriong direction ie sucks instead of blows then use the other connection.



Just to kind of clarify, on standard systems L1, L2 and L3 are the classifications for incoming three phase system and U,V and W or U1,V1 and W1 are the outgoing. So with this setup we are assuming that you are correct with the supply to the presscontrol and the earth and U connection would be earth and Live in one direction and earth and V would be for the reverse direction.



I hope this helps although I know there are better sparkies than me on the forum who will probably advise you better.



Paul

waddo


Joined: 29/11/2008
Posts: 1966

Message Posted:
17/03/2010 20:01

Many thanks Paul, that will do me just fine. Guess I must have got it right - by luck - as the pump sucks and don't blow so will rest happy now and see what happens later on when I get all my pipe work round the garden to stay stuck together - at the moment it is happily blowing itself apart in stages!!!

rollinbones


Joined: 14/11/2008
Posts: 201

Message Posted:
17/03/2010 21:58

Hi waddo



I have fitted loeads of these and would happily come and check yours..... alsways in the area no fee...

rollinbones


Joined: 14/11/2008
Posts: 201

Message Posted:
17/03/2010 21:59

andn in case the spell checkers are out ( loads)

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
17/03/2010 22:33

Nothing wrong with the information above except for the direction of rotation.

In a three phase system, the direction of rotation can be reversed by swapping any two phases.

In a single phase system, changing places between Neutral and Live makes no difference. The direction of the rotation is determined by how the capacitor is connected internally. No capacitor is used for small fans and the direction of rotation is determined by the short circuit winding (usually only a couple of turns) on the edge of the steel poles.

ismet

Soupseed


Joined: 30/11/2009
Posts: 101

Message Posted:
18/03/2010 00:18

from top to bottom}

live

neutal

earth

earth

neutral

live