Legalities of incorrect polarity upon purchase.

[gazzamikes]

I know the feeling! When I was working as a mechanical engineer every time a machine went down I was pushed to get it repaired and numerous times dropped things in the printing presses. Glad you've sorted it!

 

[wade88]

Well i've sorted the basic elements now the thing wont run in sync with the machine is feeding ( a volumetric form fill and seal machine) so, i am feeling decidedly beaten this week. Too many issues occurring that i simply don't have the knowledge to repair safely and effectively.

I have had to resort to outside help..... it's like asking the wife for directions. I need beer tonight, lots of it.

 

[44ALLAN]

Oh it could have been had i decided to check for correct polarity first and disengaged the motor prior to starting it up. Simply case of more haste less speed mate. Everyone on my back 24/7 here to have things working and machine down time to 0.1%, so i was clearly a little hasty turning it on, and also didnt expect the plug to have been wired backwards in the place.

Everyday is a school day

Amen to that mate still learning now and well into my 50's lol
Just out of curiosity...........how was the plug wired 'backwards'?
L1 to L3 or something like that?

 

[Knobhead]

The standard is L1, L2, L3 = clockwise rotation looking at the drive end. Works 50% of the time.
I had a contracts manager proudly tell me that the 100+ motors his lads had wired up would all go the correct way. I hadn’t the hart to tell him the 1KV incomers were reversed. He got it 100% wrong and I legged it when he came looking for me.

If you’ve got a drive that is liable to be damaged if it runs in reverse the simple answer is split the motor coupling or remove drive belts. You can’t blame the manufactures if you didn’t carry out this basic check.

 

[wade88]

Phases were just terminated into any terminal. No order.

Yea Tony i didnt make the check before hand correct.

But having said that I wouldnt expect to buy a kettle, and have it cool my water down instead of heat it up. Apparently in industry as you are all remind me, you don't necessarily get what you pay for, and when it is delivered to your doorstep, check it thoroughly first before assuming its correct/ and or works the way you expect it too.

I'm sure after i have been doing this for 20 years i will also be a fountain of enterprising knowledge.

This i have taken on board.

 

[gazzamikes]

The biggest problem I found was with German machines especially our presses they have the brown black grey but there's was black brown grey, always cases problems

 

[BlueToBits]

Could you not squeeze a phase monitoring relay into the control box? You can pick one up for less than £50.00

 

[44ALLAN]

- - - Updated - - -

Wade.
What's happened here is something that has probably happened to every single spark who has wired up a 3 phase motor...........it's gone in reverse.
Checking the isolator/contactor/plug wiring etc will not make one jot of difference so no-one to blame there least of all you mate.

I learnt many years ago never to trust another sparks work so as a matter of course now I always open all panels and plugs etc and check/test the wiring before energising........whatever it is.
Good practice to get into that frame of mind mate and hope you don't think I'm having a pop.............not intended just trying to be helpful for future reference.

 

[ian.settle1]

When the machine was tested in China it may have gone the correct way but it comes down to the fact the motor should have been run without the load connected to check that the motor was going in the right direction before the load was applied or you should have started it and stopped it straight away just to check the direction before it got up to speed.

 

[wade88]

It's a bucket lift conveyor, its on, or off, no wind u speed, no alteration in speed, it just runs and stops. So i turned it on to run and it ran backwards, within those few seconds, its destroyed several parts on the machine. Hence the annoyance.

But at the time of the OP, i was unaware it is so common in industry to have a jumble of phases on gear so i shall endevour in the future to take nothing for granted and expect nothing to be consistent.