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etpm@whidbey.com: Mar 15 10:09AM -0700 I have a small VFD, Huanyang model HY02D223B that is powering a sub spindle that I added to a CNC lathe. I have not interfaced the VFD with the CNC control and don't plan to. The manual says a line reactor should be used for power factor correction. It should be capable of handling 12 amps at 250 volts, have 2.5 mH inductance, and 5% impedence. Besides power factor correction does the line reactor do anything else that might prevent any problems? Such as stopping any noise that might interfere with and CNC machines that are wired into the same circuit breaker panel? I don't really care much about the power factor correction right now. My power company won't charge me less if the power factor is corrected, I just don't use that much juice. Virtually all the line reactors I see for sale are 3 phase models. I am powering the VFD with single phase but could use 3 phase. Do all lines running to the VFD need to go through a line reactor for proper operation? I could use 3 phase to power the VFD or maybe I could just use 2 of the three windings in a 3 phase reactor. I dont know if that would work so I am asking here. Thanks, Eric

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 15 10:40AM -0700 http://www.coilws.com/index.php?main_page=index&cPath=208_292   Peter Wieck Melrose Park, PA

Jon Elson <elson@pico-systems.com>: Mar 15 01:32PM -0500 On Fri, 15 Mar 2019 10:09:03 -0700, etpm wrote:     > else that might prevent any problems? Such as stopping any noise that > might interfere with and CNC machines that are wired into the same > circuit breaker panel? Yes, I had a few pieces of computer-type gear that were affected by a VFD on my CNC mill. I put a heavy-duty commercial line filter box on it, and all the interference went away. This is an LC filter, not just a reactor. I found a suitable filter in my junk.   Jon

etpm@whidbey.com: Mar 15 01:28PM -0700 On Fri, 15 Mar 2019 13:32:31 -0500, Jon Elson <elson@pico-systems.com> wrote:   >all the interference went away. This is an LC filter, not just a reactor. >I found a suitable filter in my junk.   >Jon Thanks Jon. As it happens I have an LC filter I removed from an old CNC mill. Made by RK Electric. There is a schematic on the front that shows three 220 ohm resistors all connected together at one end in a star formation. The other end of each resistor is connected to a .47 mfd cap. From the other end of each cap is a wire. The device is rated at 600 volts. I don't know how to use it but I imagine it is just connected across the three incoming power wires. With single phase can just any two wires be used? Thanks again, Eric

etpm@whidbey.com: Mar 15 01:46PM -0700 >just any two wires be used? >Thanks again, >Eric I meant Wye connection. Looking online I see that it is a surge suppressor. Oops. Anyway, it shows the device connected across the motor wires. They do sell single phase ones too and I may have a couple. The manual shows the reactor being connected to the incoming power leads so I guess an LC filter should be too. Especially since the VFD manual says to not connect anything across the output. Switches and capacitors are specifically mentioned. Eric

Jeff Liebermann <jeffl@cruzio.com>: Mar 15 09:22PM -0700 On Fri, 15 Mar 2019 13:32:31 -0500, Jon Elson <elson@pico-systems.com> wrote:   >all the interference went away. This is an LC filter, not just a reactor. >I found a suitable filter in my junk.   >Jon   Ditto here. It's difficult to see the filters, there are 6 Corcom line filters in this mess that isolate the servo driver boxes from the power line. Two filters are partially visible under the tangle of cables between the upper two boxes. There's also a power line filter going to the controller: <http://www.learnbydestroying.com/jeffl/pics/CNC-conversion/slides/CNC-conversion-02-001.html> More: <http://www.learnbydestroying.com/jeffl/pics/CNC-conversion/> I have no idea if they were really necessary because I insisted that they be included in the initial build and never tried to run any jobs without them.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann <jeffl@cruzio.com>: Mar 15 09:34PM -0700 >Especially since >the VFD manual says to not connect anything across the output. >Switches and capacitors are specifically mentioned.   We have the VFD powering only the spindle motor, which requires 3 phase power from a single phase source. We have no filtering on the VFD output. Everything else I previously mentioned is powered by 220VAC single phase, which is full of AC line filters. If you suspect that the spindle power is somehow getting into the computah, perhaps some shielding conduit might be an easy fix?   <http://eecoonline.com/vfd-load-filters/> See comments under "VFD Load Filters".   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Ralph Mowery <rmowery28146@earthlink.net>: Mar 16 10:21AM -0400 In article <uiuo8e9bvmtqcttfg9suv737s1e6a5khi4@4ax.com>, jeffl@cruzio.com says... > some shielding conduit might be an easy fix?   > <http://eecoonline.com/vfd-load-filters/> > See comments under "VFD Load Filters".   Where I worked we had hundreds of VFDs. They ranged from around 1/2 hp to over 200 hp. Nothing but the motor goes on the output. On the supply lines which were mostly 480 v 3 phase or some 120 V single phase was a reactor. This is to keep the electricl noise generated by the VFD out of the supply lines.   As the plant had many microprocessors/PLC and other computer equipment the AC lines needed to be somewhat clean. Very difficult with all the various equipmnet in the plant. Some times strange thing would seem to hapen due to a spike of noise. It may not be on the AC line powering the equipment,but on some of the sensor wiring.

Jeroni Paul <JERONI.PAUL@terra.es>: Mar 15 06:54PM -0700 I have a mosquito trap with a circline 10W UV fluorescent bulb and a fan, the bulb went bad and it proved difficult to get a replacement. Now I would like to run the bulb only at night to extend its life and I tought to add an LDR, some transistors and a relay to run the bulb only at night.   Problem is the same inverter runs the bulb (CFL like circuit) and the fan, and the fan must never stop. The inverter has separate transformers for the bulb and fan but the drive circuit seems shared.   My concern is if I can place the relay in series with one of the four bulb wires to turn it on and off safely. The inverter ran for several months with a blown bulb so it has no problem to run without a load. But can it be damaged if the bulb is disconnected while powered?

Adrian Caspersz <email@here.invalid>: Mar 16 02:36AM On 16/03/2019 01:54, Jeroni Paul wrote: > I have a mosquito trap with a circline 10W UV fluorescent bulb and a fan, the bulb went bad and it proved difficult to get a replacement. Now I would like to run the bulb only at night to extend its life and I tought to add an LDR, some transistors and a relay to run the bulb only at night.   > Problem is the same inverter runs the bulb (CFL like circuit) and the fan, and the fan must never stop. The inverter has separate transformers for the bulb and fan but the drive circuit seems shared.   > My concern is if I can place the relay in series with one of the four bulb wires to turn it on and off safely. The inverter ran for several months with a blown bulb so it has no problem to run without a load. But can it be damaged if the bulb is disconnected while powered?   How complex would you like this?   I'd separate things and run the fan from it's own power supply that also supports a circuit that   1) switches the fan off after the lamp has cooled, 2) doesn't allow the inverter to turn on if the fan is not running   A bit of simple logic, or a micro....   -- Adrian C

tabbypurr@gmail.com: Mar 16 02:17AM -0700 On Saturday, 16 March 2019 01:54:38 UTC, Jeroni Paul wrote:   > I have a mosquito trap with a circline 10W UV fluorescent bulb and a fan, the bulb went bad and it proved difficult to get a replacement. Now I would like to run the bulb only at night to extend its life and I tought to add an LDR, some transistors and a relay to run the bulb only at night.   > Problem is the same inverter runs the bulb (CFL like circuit) and the fan, and the fan must never stop. The inverter has separate transformers for the bulb and fan but the drive circuit seems shared.   > My concern is if I can place the relay in series with one of the four bulb wires to turn it on and off safely. The inverter ran for several months with a blown bulb so it has no problem to run without a load. But can it be damaged if the bulb is disconnected while powered?   a small halogen bulb also works to attract bugs.     NT

Jon Elson <elson@pico-systems.com>: Mar 15 01:35PM -0500 On Fri, 15 Mar 2019 16:37:20 +0800, Rheilly Phoull wrote:   >> core in solder that thin seems impossible. and this has five. How do >> they make it?   > Google "Extrusion"   I don't actually know, but I'm wondering if it is done by starting with a big bar and then rolling and stretching it, kind of like wire drawing. It seems extrusion won't work, as that would leave the holes in the solder wire empty. But, maybe there's a trick to it. The nozzles that fill the holes would have to be REALLY tiny, and then hollow for the flux? Seems like it would never work.   Jon

John Robertson <spam@flippers.com>: Mar 15 12:20PM -0700 On 2019/03/15 3:25 a.m., whit3rd wrote: >> core in solder that thin seems impossible. and this has five. How do >> they make it?   > A lot like putting stripes on toothpaste, which is also clearly impossible.   I'm still trying to figure out how they put the filling in the Cadbury Caramel bars...   John ;-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 15 12:58PM -0700 It starts, as you suggest, as a much larger tube, and then is drawn to the correct diameter.   https://static.makeuseof.com/wp-content/uploads/2015/04/rosin-core-solder-640x240.jpg Is a picture of single-core solder. 5-core takes a little bit more care, and will not be possible with the more brittle formulas.   The key is keeping the tin/lead admixture annealed during the entire drawing process, yet not so warm as to melt. Noble metals do much better at this than others, and lead is very nearly a metaloid in any case - so this is not a casual exercise. The multiple cores serve to spread the rosin more evenly, so it is not just hype.   Peter Wieck Melrose Park, PA

Martin Gregorie <martin@mydomain.invalid>: Mar 15 08:17PM On Fri, 15 Mar 2019 12:20:08 -0700, John Robertson wrote:   > I'm still trying to figure out how they put the filling in the Cadbury > Caramel bars...   Form the caramel bars, freeze them, dip in a vat of hot chocolate and lay flat on a cold surface until set?   -- Martin | martin at Gregorie | gregorie dot org

John Robertson <spam@flippers.com>: Mar 15 02:05PM -0700 On 2019/03/15 1:17 p.m., Martin Gregorie wrote: >> Caramel bars...   > Form the caramel bars, freeze them, dip in a vat of hot chocolate and lay > flat on a cold surface until set?   There was an musical ad in the 70s that asked that question as I recall...but I can't remember how it went other something like "How do they put the caramel in Cadbury's bar?"   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

tabbypurr@gmail.com: Mar 15 02:37PM -0700 On Friday, 15 March 2019 20:17:53 UTC, Martin Gregorie wrote: > > Caramel bars...   > Form the caramel bars, freeze them, dip in a vat of hot chocolate and lay > flat on a cold surface until set?   "An enrober operates by first dipping the bottom part of a confection in a bath of liquid (chocolate is the primary coating used with such equipment). The item then passes through a curtain of liquid to complete the task."     NT

Martin Gregorie <martin@mydomain.invalid>: Mar 15 09:58PM On Fri, 15 Mar 2019 14:37:57 -0700, tabbypurr wrote:   > a bath of liquid (chocolate is the primary coating used with such > equipment). The item then passes through a curtain of liquid to complete > the task."   Yes, that makes sense, both as a way to get a coating on the underside and of the shape or the top and side coating.   Do you know whether the core needs to be chilled? I'm just thinking that some fillings are very soft and that chilling them would stop them deforming while being coated and then while the chocolate is setting.     -- Martin | martin at Gregorie | gregorie dot org

tabbypurr@gmail.com: Mar 16 02:14AM -0700 On Friday, 15 March 2019 21:58:20 UTC, Martin Gregorie wrote:   > Do you know whether the core needs to be chilled? I'm just thinking that > some fillings are very soft and that chilling them would stop them > deforming while being coated and then while the chocolate is setting.   Some fillings are chilled - ice cream certainly has to be     NT

bitrex <user@example.net>: Mar 15 02:03PM -0400 >> That'll do it.   > transplant time.   > NT   Replacements of the same type are $2.50 at mouser but _sigh_ there must be some corollary to Murphy's Law that while 2 day shipping is pretty cheap you'll always discover you need something on a Thursday.

bitrex <user@example.net>: Mar 15 02:06PM -0400 On 03/15/2019 02:03 PM, bitrex wrote:   > Replacements of the same type are $2.50 at mouser but _sigh_ there must > be some corollary to Murphy's Law that while 2 day shipping is pretty > cheap you'll always discover you need something on a Thursday.   Ah, right this one.   <https://en.wikipedia.org/wiki/Finagle%27s_law>

dplatt@coop.radagast.org (Dave Platt): Mar 15 10:57AM -0700 >of both have some slight bending/warping that the other, more recessed >pots don't. Looks very much like impact damage to me.   >I'll swap them out and see what happens.   I picked up a nice subwoofer system with integrated amp at a local electronics flea-market last year, for about 15% of the original price. The seller said "It works fine, but the volume adjustment knob is missing." It wasn't just the knob - the whole potentiometer shaft was snapped off, inside the mounting flange. Tried it when I got it home, and the amp powered up but wouldn't play any music.   When I opened up the amp I found the dual pot bent backwards and smashed up - both halves were open-circuit. Apparently somebody had struck the pot knob quite hard, somehow, and completely wrecked it.   I removed it and tacked a couple of resistors into place to simulate a mid-scale setting on each channel, and the amp came back to life and the subwoofer worked. A $6 purchase from eBay, for a package of three dual-section 20k linear pots of the right size, and another session of soldering, and the subwoofer was as-good-as-new. Works beautifully, alongside my heavily-refurbished (from-the-same-flea-market) Minimus 77 speakers and refurbished (also-from-the-same-flea-market) Proton receiver and (made-almost-entirely-from-recycled-and-eBay-parts) Raspberry Pi media streaming player.

tabbypurr@gmail.com: Mar 15 09:47AM -0700 On Friday, 15 March 2019 13:11:36 UTC, Fox's Mercantile wrote:   > It doesn't make much if any difference. > Don't let people wind you up about impedance matching on receive > antennas.   Co-ax impedance is not critical, but choosing rf rather than baseband co-ax is.       > Generally, UHF is 3 times the VHF frequencies. What looks like a > 1/4 wave whip antenna (16-18")on VHF will look like 3/4 wave on > UHF. And will work just fine.   Try it & see.     NT

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