3 phase help

[Apache]

I'm installing a 3 phase 2 post car lift. Tested supply at breaker - phase rotation correct. Connected up using manufacturer supplied lead labelled 1,2,3. Motor makes noise but no hydraulic pressure.

Checked in control box and phase reading 1,3,2. Swapped L2 and 3 over and it works.

I'm sure supply is correct.

Currently connected via a 16A 3ph and earth plug, but was planning on hard wiring in.

Am I missing something stupid here? If it works should this be ok, or am I missing something major?

I think the Chinese or whoever wired the control box have mixed things up.

 

[Andy™]

is there a direction arrow on the motor? (often clockwise looking at the fan end of the motor towards the pump)

its common that you need to swap phases to make it turn the right direction

if youve swapped phases and it now works then i wouldnt be too worried about it tbh

 

[Apache]

Yes, clockwise if viewed from above

Thanks for the reassurance. Not very familiar with 3ph.

 

[Tony S]

I’ve never trusted manufacturer’s connection labelling when it comes to rotation, I’ve seen too many machines wrecked. Get Albert and Duggie on a pump change you could guarantee it would it would be back in the workshop next day with the rotor jambed.

 

[kerching]

Mechanical car lifts are funny when the site sparky just connects without checking rotation and the lift screws itself out of the floor going DOWN as it's expecting the L/S at the TOP to,break the down coil feed

 

[Andy™]

Mechanical car lifts are funny when the site sparky just connects without checking rotation and the lift screws itself out of the floor going DOWN as it's expecting the L/S at the TOP to,break the down coil feed

seen that happen before

 

[phil d]

seen that happen before

A friend of a friend had a garage, he moved to a bigger premises and another friend who knew about electrics moved the ramp, he cut the cables leaving a bit of each in each terminal so he'd know what went where. The machine was bolted down and he wired it, exactly as he'd removed it, the red to where the red went, the blue where the blue went and the yellow went where the yellow went, fine, then he ran the ramp, it went the wrong way and damaged the ramp. "ah, the machine's faulty" says he, "it'll never work like that". well it wouldn't now, he thought if you made sure the colours went to the same places it would work.

 

[Apache]

At least with this design it's 2 hydraulic rams that push upwards and then oil pressure is released to lower. No way there is any downwards pushing.

Just seems silly they label the terminals L1, L2 and L3, I check phase rotation on incommer and it's right and yet only works when wired 1,3,2.

These things annoy me.

 

[Rob.]

At least with this design it's 2 hydraulic rams that push upwards and then oil pressure is released to lower. No way there is any downwards pushing.

Just seems silly they label the terminals L1, L2 and L3, I check phase rotation on incommer and it's right and yet only works when wired 1,3,2.

These things annoy me.

Then the motor connection was likely changed at somepoint, this is the correct place to change it anyway.

 

[Tony S]

Mechanical car lifts are funny when the site sparky just connects without checking rotation and the lift screws itself out of the floor going DOWN as it's expecting the L/S at the TOP to,break the down coil feed

Which is why you always press "down" to check rotation.

 

[kerching]

I was called to,a brand new car body repair place a few weeks ago. State of the art place, very smart

2 poster wouldn't work....they had relocated it from another site. Opened control box and there's a USB port and a small CD!?!?!?!

i was told the manufacturers said it needed the 'cables calibrating as the limit switches would be out of Synch'

i thought it was because the W️ That wired the building made the isolators on the wall TP&E....this ramp needed a neutral!

hey ho!

 

[Andy™]

i thought it was because the W️ That wired the building made the isolators on the wall TP&E....this ramp needed a neutral!

thats why i always wire circuits with a neutral regardless of if its needed or not

 

[kerching]

thats why i always wire circuits with a neutral regardless of if its needed or not

It's a no brainier really, isn't it!

mind you he made a total of the rest of the install as well  :slap

 

[Sidewinder]

At least with this design it's 2 hydraulic rams that push upwards and then oil pressure is released to lower. No way there is any downwards pushing.

Just seems silly they label the terminals L1, L2 and L3, I check phase rotation on incommer and it's right and yet only works when wired 1,3,2.

These things annoy me.

No it will also work correctly wired 321, I was always taught to swap the outer two phases, that way, it always reads correctly L1, L2 L3 from one direction in the terminal box.

 

[Sharpend]

Yes I remember being taught that. 

 

[Tony S]

No it will also work correctly wired 321, I was always taught to swap the outer two phases, that way, it always reads correctly L1, L2 L3 from one direction in the terminal box.

It’s more obvious if you do it that way. Fun if you have a panel fed from two sources where one is reversed  :happybunny: