steam4ian
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Post by steam4ian on Sept 23, 2014 22:01:31 GMT
PS
The Lafert motor range is IE4
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bhk
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Post by bhk on Sept 24, 2014 5:38:40 GMT
Ian I have seen these and think there excellent but are on the expensive side, if money was no option it would have been a nice solution.
I ordered a drive today, so it's the step up VSD route I'm taking.
Talking to multiple suppliers one thing a few suggested was also running the existing 3phase suds pump from the drive, it will vary with that of the spindle but they have said people have found it off little inconvenience. Thoughts?
Also need to start thinking about where I'm going to put it, anyone got pictures of there installation?
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Post by Roger on Sept 24, 2014 6:47:35 GMT
Personally I think it would be a pain because it's not going to deliver anything at the slowest speeds. Still, if it's already wired in you may as well just try it, there's nothing to lose. The main thing is the spindle drive and hopefully that's soon going to be sorted.
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uuu
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Post by uuu on Sept 24, 2014 6:53:49 GMT
I've had success buying second hand inverters off ebay. The small ones are cheap, so you might find one for the suds pump. What power is the motor?
Wilf
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bhk
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Post by bhk on Sept 24, 2014 7:37:34 GMT
I've had success buying second hand inverters off ebay. The small ones are cheap, so you might find one for the suds pump. What power is the motor? Wilf Hi Wilf, Sadly postage to NZ is expensive, it's been the biggest brick wall in this process, it's actually cheaper to ship to Syria than NZ I've ended up finding a drive supplied locally. But as Roger says connect it up and see how it goes.
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Post by ejparrott on Sept 24, 2014 9:13:14 GMT
Also need to start thinking about where I'm going to put it, anyone got pictures of there installation? Are we talking about the drive or the suds?
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steam4ian
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Post by steam4ian on Sept 24, 2014 9:19:17 GMT
Sean
Use the message facility here to send me you email and I will forward details of my installation.
Ian
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bhk
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Post by bhk on Sept 24, 2014 9:53:37 GMT
Also need to start thinking about where I'm going to put it, anyone got pictures of there installation? Are we talking about the drive or the suds? The drive, suds is already neatly made by Colchester.
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Post by ejparrott on Sept 24, 2014 12:17:25 GMT
I did wonder!
Mine is a complete unit from Newton Tesla admittedly, but I've hung it on the door to the motor cabinet on the Boxford, so just nicely at my finger tips below the headstock.
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uuu
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Post by uuu on Sept 24, 2014 16:14:21 GMT
Here's mine - at least the control panel bit of it. The inverter is up on the wall where I can read off the frequency. I'm assuming you'll want to retain the starting lever on the saddle, so you won't need the buttons. I can advise a health warning on the control panels sold by a number of suppliers, which have a FWD/REV switch and a RUN/JOG switch next to one another. You're screwcutting using the JOG feature and going forward slowly. You want to back out, so you flip the switch to reverse. Only you flip the wrong switch, so when you hit start you don't get slow reverse, you get full speed forward! Wilf
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bhk
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Post by bhk on Sept 25, 2014 6:06:03 GMT
Cheers guys, I sat and designed a panel for it today. I've got a pretty good idea on how I'm going to set it up, wire it up and the functions I'll have. There will only be 2 possibly. 3 functions on my little box which will be mounted up next to the DRO once I get one, potentiometer for speed control, emergency stop. The third is possibly a stop/start for the coolant pump once I decide what to do about it I'm unsure if I could switch it on and off with a contactor if running of the drive so I might end up replacing with single phase and running it through a latching contactor. The start stop fwd reverse will all be on the apron control. The light will just be on all the time as long as the main isolator is on, reminds me to turn it off. I did get the LED driver today so have hooked it up temporally to test the durability of the system. Heaps of light and after a few hours turned on its still cold to touch.
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Post by Roger on Sept 25, 2014 7:38:14 GMT
The Start/Stop box on my cheap and cheerful suds pump packed up a while ago so I just replaced it with a switch. There's no safety issue here so I don't really know why they bother with them.
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Post by Deleted on Sept 25, 2014 11:58:01 GMT
"You might drown in a sudden deluge of suds, sir----You might, you just might !---- It's for your own safety, Sir....Just think what your children might say------We have the LAW on our side-----compliance is non-negotiable !!-------H&S Directorate are only thinking of your future health and happiness, sir !!.......NON-Compliance will result in a visit from "The Thought Police", plus you will be required to attend}--- Re-Education Classes.................YOU-------WILL------O-----BEY !!!!
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bhk
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Post by bhk on Sept 25, 2014 17:22:33 GMT
"You might drown in a sudden deluge of suds, sir----You might, you just might !---- It's for your own safety, Sir....Just think what your children might say------We have the LAW on our side-----compliance is non-negotiable !!-------H&S Directorate are only thinking of your future health and happiness, sir !!.......NON-Compliance will result in a visit from "The Thought Police", plus you will be required to attend}--- Re-Education Classes.................YOU-------WILL------O-----BEY !!!! Ahhhh bloody health and safety, luckily I work in an industry where it's not quite caught up with us just yet. But I feel for those people who do! I remover the last HSE inspection the got done at the factory while I was there, most sour people I've ever met! Rant over :-)
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bhk
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Post by bhk on Sept 25, 2014 17:33:33 GMT
The Start/Stop box on my cheap and cheerful suds pump packed up a while ago so I just replaced it with a switch. There's no safety issue here so I don't really know why they bother with them. Hi Roger, I have the contactors left over from another project so it would not be a hardship to install. They are 240v coils so I would still end up with 240v at the switch just a bit more reliable. I'm am planning on building the electric circuit to be more heavy duty than required in the aim of reliability with a lot of air to the inverter to keep it cool. After all an elephant is only a mouse built to marine specification.
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bhk
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Post by bhk on Sept 26, 2014 6:38:24 GMT
Drum switch wiring diagram, anyone understand them? I need to get this From this If someone can understand the drum switch diagram and save me work of measuring all the contacts on the switch that would be great
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steam4ian
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Post by steam4ian on Sept 26, 2014 6:50:23 GMT
Yes
Send the diagrams to my PM
Ian
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bhk
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Post by bhk on Sept 29, 2014 5:08:55 GMT
Still waiting for the VSD to turn up ....waiting waiting waiting!!! Anyway did work my way round the switch from the apron control and figured out how to wire that.
Some of those other things I had on order arrived today, drill chuck which impressively does 0.2mm to 16mm, live centre and a set of MT4 collets (3mm - 25m), these will go directly into the spindle will Need to make a drawbar once the lathe is running.
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bhk
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Post by bhk on Oct 10, 2014 18:41:56 GMT
The inverter turned up earlier in the week. With a professional exam I've been preparing out of the way yesterday morning it left me the afternoon to get on with it.
I connected it all up on bench and it run straight out the box, decided to check with a meter voltage at the motor just to be sure all is well. And I was only getting 115v. After much head scratching and checking of parameters I thought the drive must have been faulty.
I've got a friend who works on building these drives but much more powerful (MW) so I gave him a ring and he told me to measure it with an old analog meter and get back to him.
So down to the shop to pick up a cheep analog meter with much confusion as to why..... Put it on the motor and get 650v.....bloody meters faulty so take it back and exchange it put the new meter on again 650v
Rings my friend and at this point he is laughing down the phone and goes on to give the following explanation.
When it rectifies the incoming AC you end up with around 650v DC on the bus bar, its fires these out (pulse width modulation) to the motor as a made up AC waveform.
It's doing it so fast the your motor only ever sees the AC component of it but there is a DC element there, my digital meter auto ranges and this was only reading the DC component of around 115v you can read the peak pulse voltage with a analogue meter which comes out the same as DC bus voltage, If you minus the two you end up with the true AC voltage to the motor of 435v in this case.
Lesson learnt!
Good thing is got all the control function of the drive sorted, still waiting on a few parts to turn in the post but can start getting the lathe back together. Not long and I'll be making chips
Cheers Sean
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Post by andyhigham on Oct 10, 2014 18:59:31 GMT
You will never get a meaningful voltage reading. Meters are designed to read a sine wave, the output from an inverter is more like a square wave but with the on time and the off time varied with respect to each other (PWM or Pulse Width Modulation)
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