3 Phase Plug Wireing Q?

[Wyn F]

Ok this is not a wind up but a honest question to all you elecy type peeps out there

If you have a 3 phase machine, say a tyre changing machine or a hydraulic pump of some sort
(4 or 5 pin 3 phase plug if it matters)

If the machine did not have its 3 phase 4 or 5 pin plug would/should you know for sure how to wire the machine so it runs/pumps the right way, straight away (without access to a wiring diagram?)

If you wired it so it run backwards would that be a mistake, or how it is with 3 phase electrics ?

As said honest question

 

[Anguz]

all down to luck normally....

 

[Robotstar5]

Normally wire it L1 - Brown, L2 - Black, L3 - Grey (red, yellow, blue, old colours) if it runs backwards just swap any 2 over.

 

[brightspark]

look at the wires brown L 1 BLACK L2 GREY L3 AND BLUE NEUTRAL file:///C:/Users/user/Downloads/ECA-Comprehensive-Guide-to-Harmonised-Cable-Colours-(P15500812).pdf most machines it wouldnt matter if u wired it wrong way round and it ran backwards just swap any 2 wires round to reverse direction some gear must run the correct way 1st time otherwise damage to gears ect would ruin machine then it does matter . i just check with a phase rotator

 

[Robotstar5]

i just check with a phase rotator

I've just realised in nearly 40 years of working with 3 phase, I've never used a phase rotation indicator!

 

[brightspark]

I've just realised in nearly 40 years of working with 3 phase, I've never used a phase rotation indicator!

in 40 years ive only ever used it once on one machine that was installed and was noted saying do not on any circumstance run backwards or serious damage will occur

 

[Wyn F]

Luck of the draw then

Ok many thanks

 

[Spark plug]

I've just realised in nearly 40 years of working with 3 phase, I've never used a phase rotation indicator!

Strange that I was thinking about them the other day, wondering why you would ever need to know the phase rotation.

 

[Wyn F]

some gear must run the correct way 1st time otherwise damage to gears ect would ruin machine then it does matter . i just check with a phase rotator

Strange that I was thinking about them the other day, wondering why you would ever need to know the phase rotation.

Why the question
Something should have went up instead of down and busting the machine
Just wanted to know if wiring was that obvious

 

[Anguz]

only time i have ever used one, is when wiring generators to run in parallel.... it is quite important then....

 

[sparkysy]

Hi I use mine weekly but we do a lot of farms where the farmer has had a go and co@ked it right up! They are a useful tool and not that expensive any more mine will do both motor and supply rotation! Always nice to get it right the first time impress the customer

 

[BrokenBiker]

I don't so enough 3 phase to need one, the only 3 phase I have done since starting out on my own is motors that can be removed from the machine so you can see which way its running.

when I was a spark in a factory we used one fairly regularly as the one set of machines has a table moving on a ball screw at a fixed speed, and if a table was fairly close to one end when the motor packed up it would cause about 30k worth of damage to the machine if it was sent the wrong way. easier to work out phase rotation than to strip the machine and crank the table across by hand

 

[Robotstar5]

Just reminded me, one of the other shifts changed an inverter which drove backwards due to wrong phase rotation, the bit it was driving managed to reverse the line into the previous station which corrupted the build data and took a while top resequence the line.