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Amazing okay, and yeah 240v is what I’m after thanksKim before you buy an led block let me have a look here I think I have some spare - is it 240v you need?
Amazing okay, and yeah 240v is what I’m after thanksKim before you buy an led block let me have a look here I think I have some spare - is it 240v you need?
I must admit I’m just as confused.
No probs, pm me your address and I’ll post it outAmazing okay, and yeah 240v is what I’m after
Oh so you’re not saying I need anymore than what I have already shown? I did know what you’re saying here.OK, I thought you might be after that explanation The pot has three legs, the middle leg is the slider, the centre point as represented in my diagram. The two outer legs are the top and bottom resistor connections. One of the outer pair will go ton "COM" on the VFD. The other will go to "5v/12v" or it may be 10v depending on your VFD. The middle contact goes to the "Freq. Adjust" or whatever it is that they refer to it as. If you connect the outer two the wrong way round your pot will work in reverse i.e. turning clockwise will slow the motor, anti-clockwise will speed it up. Just reverse them.
All you need is a "10k ohm linear 3 terminal potentiometer" - 10k ohm 3 linear terminal potentiometer | eBayOh so you’re not saying I need anymore than what I have already shown? I did know what you’re saying here.
My VFD was (far) toward the cheaper end of the range and didn't have the circuitry for a brake resistor. My understanding was that, without this, you aren't going to get much in the way of electric braking.
By the way, I'm not sure why we're making such a big thing of this (and am happy to be corrected) but adding a VFD to a lathe that has previously been controlled by a manual switch / contactor isn't going to decrease the electric braking or increase freewheeling on stop, is it
Needs a long shaft for the mount I have. I did have a bit of a look around.All you need is a "10k ohm linear 3 terminal potentiometer" - 10k ohm 3 linear terminal potentiometer | eBay
Can be had from £2 or £3 (and I'm sure RS can do them even cheaper). The only thing that was throwing me was whether you needed a long neck if you wanted to fit it inside the head of your lathe rather than mount it in a separate box.
Unfortunately I ordered t before you replied but I’ll just try it. Not like I’m operating it like In a machine shop.For the pot, use a wire wound or cermet type as in your original link. Carbon/polymer tracks dont last 5 minutes and on a lathe will be getting a lot of use. Last thing you want on a lathe is the speed jumping around, Ive had it, not pleasant!
Ebay or amazon for "wx112" will get you a decent wirewound of chinese origin. The body of it is 40-50mm, large, unsure if it will fit your plastic bits, plain 6mm round shaft. Ive used a few of these and they last well.
Vfd's usuallly want a 5k linear type.
It wasnt swarf or dirt. I wore out three polymer types mounted in the vfd enclosure, in a month or two each.Kram makes a good point about wirewound in the shop, but it does depend where it goes. Mine is mounted on an enclosure 3ft above the lathe so I have no fear about the cheap polymer pot lasting up there.
If I was mounting it on the actual machine then I might consider a wirewound one.
Nice vid.I made a little video with my progress so far
I wasn’t going to but someone said about that. I’ll probably put some in.Nice vid.
Are you putting fan(s) into the box that contains the VFD? They can run hot and like to have air flowing over them.
Does anyone have recommendations for somewhere to source a continuous flat drive belt. I’ve seen a place for one to join but I really don’t want to listen the clatter of the metal clip. It’ll drive me up the wall.
Won’t they fall off? I did think of converting the pulleys but the drive one will be a pain.If you can fit a continuous one, get a normal poly-vee belt of the correct length. You don't need one nearly as wide as the leather belt as they transmit a lot of energy, don't stretch annd have good grip on the flat pulleys.
If you can't (because it means removing the spindle or something) get one that's too long and splice it. I've spliced several and they all worked great.
Metal clip on my mill. Unbearable noise above 1000rpm.Does anyone have recommendations for somewhere to source a continuous flat drive belt. I’ve seen a place for one to join but I really don’t want to listen the clatter of the metal clip. It’ll drive me up the wall.
had no idea those 'marxman' pens existed, proper gamechangerI made a little video with my progress so far