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| Oh Blimey I bought a CNC Lathe !!!! |
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| Pete.:
We have to turn up the RCD mA when we hire large portable generators. They don't like the big motor startups, even on the newest euro-start machines. It's caught a few of the guys out, had them opening up the commando plugs looking for water etc. So you've ran the spindle then. What's left to do before it'll actually cut chips? |
| awemawson:
Well I need to learn a lot for starters! I think that the V axis issue is a referencing one. I'm not sufficiently familiar with the operation to have much confidence jogging things around without bits touching each other. I've not yet got the tool turret to index, nor the powered tooling to turn, but hey who wants to finish a good book. :lol: |
| lordedmond:
don't put to much faith in those RCD's they can make you think you have all the bases covered but get across two phases one in each hand and its good night sweetheart :zap: yes they do a good job but they are not the be all and end all most 240 vac equipment that has a delta suppression cap network ( most of the variable speed lathes ) fall into this will trip a domestic RCD due to the leakage on the caps ( the inrush can also trip them ) but just a thought when yo have run the spindle for a while and got some work out of it ( nice and warm ) it may well be OK on the lower RCD ( it may be damp ) but I will guess that its the odd order harmonic suppression circuit that may well be the cause Stuart |
| awemawson:
I don't think the rcd issue is leakage in the conventional sense of ohms to earth due to damp or poor insulation. The inverter / chopper spindle drive produces quasi AC by fast switching a DC rail. This inevitably produces a high frequency source that through the stray capacitance of the wiring gives sufficient 'leakage' current to trip some devices. The cheaper PC power supplies are notorious for this. http://www.gtproductions.com.au/Mopping%20Up%20Earth%20Leakage.pdf |
| lordedmond:
If its got one of those fitted then I am surprised that the 100ma one held up OT when I was at work I was with NWB as a supervisor in the facilities dept ( engineering ) we had a pretty hefty cable burn out about 150 amp TP&N 4 core but only the neural was affected , this cable was only feeding a office section with many PC mainly Dell's , the cable was duly replaced , but being me I was not satisfied that we had the problem buttoned down so out came the tong testers , red was 30 amp yellow was 32 amp blue was 28 amp so we were balanced ok , the shock came when we tested the neutral over 200 amp , out came the scope it was all odd order harmonics 7th and 9th That was all down to the switch mode psu in the Dell's they were overlaying the 50hz with a lot of HF and causing the cable to only carry the current in the skin ( high frequency skin effect ) keep up the good work you are very close now the winning post is only 1 fault away Stuart |
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