Temptation...

Andrew thanks for the feedback, I'll give them a call to chat about what I need and price one up.

Peter

Reply to
Peter Neill
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I use a Transwave static 5hp converter too to run the bridgeport sized mill, Colchester Student lathe and 3 phase bench grinder. Brilliant bit of kit and far cheaper than having 3 phase brought in from the street. Also absolutely no problems with it in 15 years. I do need to switch one of the big machines on first though to soak up some of the supply before starting the grinder as the motor in it is too small for the converter. I forgot once, started it and left it to find a tool that needed sharpening and by the time I got back a couple of minutes later it was smoking and the casing was too hot to touch. It's a big FO 8" grinder too so the casing is huge. God knows how much power it had soaked up to get 20 kilos of metal that hot that fast. Fortunately it suffered no lasting ill effects as far as I can tell. I had a horrible feeling I'd melted everything inside it. I switched it off and waited anxiously for an hour while it cooled down and it started back up again just fine. Phew.

Same applies to the little cross feed motor on the mill and the suds pump motor. I need the main spindle motor running before starting either of them up but then it always is anyway. I could have bought a smaller converter but was advised to have one a bit bigger than the combined capacity of all the machines it might run so I could have them all on together if I wanted. I think that was good advice and often do have them all running together but I could probably still have managed with a slightly smaller model. There are six power output settings on the converter so theoretically you can adjust it to suit how many machines are running. Strangely it seems to handle one or all three quite happily on the same position - number 3 out of 6 so I rarely need to change that unless I'm trying to run a machine at very high speed in which case it might need position 4.

The only quirk with converters is you need to switch machines on in the order of their motor size or the one that's already on will cut out. So if I have the mill running I can't start the lathe or the mill will click off. The other way round works fine so I just plan ahead and switch the lathe on first if I want to turn something while the mill is in the middle of a long flycutting op.

A minor whinge is that machines don't always want to run happily at their highest possible speed on a converter. The mill is happy but the lathe prefers being at 900 rpm or less. Top speed is 1200 I think. I rarely use more than 600 anyway though so it doesn't affect me. Maybe it's just my old lathe though and not the converter's fault. In fact maybe that's also why the mill clicks off when I switch the lathe on. Dunno and don't care as I've worked round it well enough for many years.

Reply to
Dave Baker

I run a converter, I bought a static converter and got a " donkey " motor, that free runs to give a nice start and allows me to run small motors. I also packed a pair of capacitors on the lath motor contactor, which means I don't need to adjust the power rating when I use it. ( the lath is 7.5 kW, my next biggest motor is 2.5 kW, and the " donkey" is 4 kW ). This set up has worked well for me for the last four years.

Reply to
Jonathan Barnes

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