What do I do with neutral?

My "new" mill has a two speed three phase motor. The wiring to the machine is 5 wire, with a neutral. The plug on the
side of my old Transwave static converter has 4 wires.
Now the plug isn't a Transwave fitting (I put it on) so don't blame them but how should I sort this one out? Will there be a netrual in a static converter? If so where or do I just ignore it?
Charles
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Depends on the switchgear in the machine. Often they use the neutral for 240V coils on the contactors, or for the transformer for LV lighting. If neither, you can probably ignore it.
Tim
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Forgot to say that your converter is unlikely to have a neutral
Tim
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Ive just had this problem myself ..
so i can give you an answer...this is what happened in my case.
first of all
having neutral means that L1 L2 and L3
actually cant be mixed up
you see L1 is your mains positive (live) goes directly through the phase converter unchanged ...
so the neutral is its return path ...to any neutral that is within the same area covered by the consumer RCD
so you basically wire the neutral back to the consumer unit ...
and L1 has to be in the right place .
all the best.markj
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a
There is a chap on ebay selling three phase transformers specifically to give a neutral in these circumstances - also Transwave will (at a price) supply converters with a neutral. It's likely that you don't actually need neutral if your control gear is rewired
AWEM
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Identify where the wires go.Assume three phases,neutral and earth.Most machine tool builders don`t use a neutral as coil voltages were either 415 using two phases or lower using two phases to feed a transformer.The neutral may have been added by someone for a lo-volt lighting transformer or the guy who put the cable in may have been like me and only uses five core cable in case... I have never had a German machine that needed a neutral. There won`t be a neutral coming out the transwave. Mark.
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On Sat, 21 Mar 2009 15:54:40 -0700 (PDT), snipped-for-privacy@ems-fife.co.uk wrote:

Thanks for the advice chaps.
I've learnt a couple of things tonight. The primary one is to open the bloody Transwave box before posting a question. The model that I have is a SMA - not the formula milk but one of these: http://www.simplypowersupplies.com/pdf/sma.pdf Lo and behold there's a terminal strip inside with the 3 output phases and an extra output teminal called "neutral". Silly arse me ignored that when I fitted a 4 pin 16a socket on the outside. Will give it a whirl in the morning.
And Mark, you're probably right that German machines don't need a neutral and it may well have been some fitter in English Electric Valves having a similar cable usage strategy.
Charles
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On Sat, 21 Mar 2009 23:17:05 +0000, Charles P

Wired it up without a neutral (it was Sunday and I only had 4 pin plugs) and hey presto, it runs fine on both speeds and the feed motors run fine aswell. You live and learn
Charles
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