Is there such a thing as a bi-directional LED where each polarity is the same color? I can find plenty of 3mm LED's where each direction is a different color (bi-color), such as: <https://www.digikey.com/catalog/en/partgroup/3mm-and-5mm-bi-color-led-lamps/34242> <https://www.digikey.com/catalog/en/partgroup/3mm-bi-color-round-with-domed-top-led-lamp/39576> but none where both directions are the same color (bi-directional). I'm replacing about six 4PDT 24VDC 5A contact relays used in a Shizuoka ST-N vertical mill with a Bandit controller. The old relays do NOT have any LED's wired across the coils. However, every replacement relay I was able to find has an LED across the coil. <https://i5.walmartimages.com/asr/cbda1e6b-c21a-45da-9d6e-406acee02e16_1.6f3dc3808c0e41916464bc079f038faf.jpeg> The series resistor is 5.0K. The problem is that the (defacto??) standard for the polarity of the DC relay coil needed to light the LED is the reverse of how the controller is wired. It's a moderately easy fix to open the relay and reverse the LED polarity. However, I thought it might be nice to have the LED work with either polarity. Different colors for each direction are an option but I don't want to receive any confusing questions because these relays will be used on multiple machines, some of which are wired for standard polarity relays. I could cram in 2 LEDs back to back, if there's room. I could just remove the LED's like in the original relays. However, I prefer the more elegant bi-directional LED if available. Any clues as to a source? -- 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
Need same color bi-directional LED 3mm
Started by ●October 24, 2018
Reply by ●October 24, 20182018-10-24
torsdag den 25. oktober 2018 kl. 01.09.19 UTC+2 skrev Jeff Liebermann:> Is there such a thing as a bi-directional LED where each polarity is > the same color? > > I can find plenty of 3mm LED's where each direction is a different > color (bi-color), such as: > <https://www.digikey.com/catalog/en/partgroup/3mm-and-5mm-bi-color-led-lamps/34242> > <https://www.digikey.com/catalog/en/partgroup/3mm-bi-color-round-with-domed-top-led-lamp/39576> > but none where both directions are the same color (bi-directional). > > I'm replacing about six 4PDT 24VDC 5A contact relays used in a > Shizuoka ST-N vertical mill with a Bandit controller. The old relays > do NOT have any LED's wired across the coils. However, every > replacement relay I was able to find has an LED across the coil. > <https://i5.walmartimages.com/asr/cbda1e6b-c21a-45da-9d6e-406acee02e16_1.6f3dc3808c0e41916464bc079f038faf.jpeg> > The series resistor is 5.0K. The problem is that the (defacto??) > standard for the polarity of the DC relay coil needed to light the LED > is the reverse of how the controller is wired. > > It's a moderately easy fix to open the relay and reverse the LED > polarity. However, I thought it might be nice to have the LED work > with either polarity. Different colors for each direction are an > option but I don't want to receive any confusing questions because > these relays will be used on multiple machines, some of which are > wired for standard polarity relays. I could cram in 2 LEDs back to > back, if there's room. I could just remove the LED's like in the > original relays. However, I prefer the more elegant bi-directional > LED if available. > > Any clues as to a source?if you can find any: https://uk.rs-online.com/web/p/visible-leds/8623027/
Reply by ●October 24, 20182018-10-24
Jeff Liebermann wrote...> > Is there such a thing as a bi-directional LED where each > polarity is the same color?https://www.manufacturer.lighting/info/64/ AC LEDs, with two sets of back-to-back LEDs, are available for high-voltage high-light-level LED assemblies. For low light levels running from AC, people just use a back diode and run the LED half-cycle at 60, etc., rather than 120Hz. -- Thanks, - Win
Reply by ●October 24, 20182018-10-24
On Thursday, 25 October 2018 00:09:19 UTC+1, Jeff Liebermann wrote:> Is there such a thing as a bi-directional LED where each polarity is > the same color? > > I can find plenty of 3mm LED's where each direction is a different > color (bi-color), such as: > <https://www.digikey.com/catalog/en/partgroup/3mm-and-5mm-bi-color-led-lamps/34242> > <https://www.digikey.com/catalog/en/partgroup/3mm-bi-color-round-with-domed-top-led-lamp/39576> > but none where both directions are the same color (bi-directional). > > I'm replacing about six 4PDT 24VDC 5A contact relays used in a > Shizuoka ST-N vertical mill with a Bandit controller. The old relays > do NOT have any LED's wired across the coils. However, every > replacement relay I was able to find has an LED across the coil. > <https://i5.walmartimages.com/asr/cbda1e6b-c21a-45da-9d6e-406acee02e16_1.6f3dc3808c0e41916464bc079f038faf.jpeg> > The series resistor is 5.0K. The problem is that the (defacto??) > standard for the polarity of the DC relay coil needed to light the LED > is the reverse of how the controller is wired. > > It's a moderately easy fix to open the relay and reverse the LED > polarity. However, I thought it might be nice to have the LED work > with either polarity. Different colors for each direction are an > option but I don't want to receive any confusing questions because > these relays will be used on multiple machines, some of which are > wired for standard polarity relays. I could cram in 2 LEDs back to > back, if there's room. I could just remove the LED's like in the > original relays. However, I prefer the more elegant bi-directional > LED if available. > > Any clues as to a source?I've seen such LEDs, know nothing about suppliers though. You might have to put up with a bridge rectifier if you want it to light both ways the same colour, or 2 LEDs. As well as the obvious configurations I suppose there's always the option of 1 LED, 2 resistors & 2 diodes. : +-----|>|----+-----|<|-------+ : | | | : ------+ LED +------ : | | | : +-----R------+------R--------+ NT
Reply by ●October 24, 20182018-10-24
On Wednesday, October 24, 2018 at 8:15:38 PM UTC-4, Winfield Hill wrote:> Jeff Liebermann wrote... > > > > Is there such a thing as a bi-directional LED where each > > polarity is the same color? > > https://www.manufacturer.lighting/info/64/ > > AC LEDs, with two sets of back-to-back LEDs, are available > for high-voltage high-light-level LED assemblies. For low > light levels running from AC, people just use a back diode > and run the LED half-cycle at 60, etc., rather than 120Hz.Huh, can you put an led in the middle of a diode bridge, more voltage drop.... George H.> > > > -- > Thanks, > - Win
Reply by ●October 25, 20182018-10-25
On 2018-10-24, Jeff Liebermann <jeffl@cruzio.com> wrote:> Is there such a thing as a bi-directional LED where each polarity is > the same color?I've seen some at 75V> I can find plenty of 3mm LED's where each direction is a different > color (bi-color), such as: ><https://www.digikey.com/catalog/en/partgroup/3mm-and-5mm-bi-color-led-lamps/34242> ><https://www.digikey.com/catalog/en/partgroup/3mm-bi-color-round-with-domed-top-led-lamp/39576> > but none where both directions are the same color (bi-directional). > > I'm replacing about six 4PDT 24VDC 5A contact relays used in a > Shizuoka ST-N vertical mill with a Bandit controller. The old relays > do NOT have any LED's wired across the coils. However, every > replacement relay I was able to find has an LED across the coil. ><https://i5.walmartimages.com/asr/cbda1e6b-c21a-45da-9d6e-406acee02e16_1.6f3dc3808c0e41916464bc079f038faf.jpeg> > The series resistor is 5.0K. The problem is that the (defacto??) > standard for the polarity of the DC relay coil needed to light the LED > is the reverse of how the controller is wired.a lazy man would go over the led with a black paint marker and call it a day. same colour both ways. -- When I tried casting out nines I made a hash of it.
Reply by ●October 27, 20182018-10-27
On 24 Oct 2018 17:15:19 -0700, Winfield Hill <hill@rowland.harvard.edu> wrote:>Jeff Liebermann wrote... >> >> Is there such a thing as a bi-directional LED where each >> polarity is the same color? > > https://www.manufacturer.lighting/info/64/> AC LEDs, with two sets of back-to-back LEDs, are available > for high-voltage high-light-level LED assemblies. For low > light levels running from AC, people just use a back diode > and run the LED half-cycle at 60, etc., rather than 120Hz.Thanks. Sorry for the delayed reply. All the "AC LED" hints under the above description seem to be 117/220VAC powered and seem to refer to much larger light bulbs and strips. There's very little room for a diode bridge or a 2nd LED. The only way I could make that happen is to redesign and 3D print a new white plastic LED frame. The plastic is there to provide voltage isolation between the solenoid wires and the relay contacts and frame: <http://www.learnbydestroying.com/jeffl/crud/Omron%20relay.jpg> I could cram a small SMD bridge along the side of the relay but would require precision soldering under a microscope, and is too much work. Similarly, I tried to replace the 3mm LED with two parallel SMD LED's. It worked, but again required too much work. The typical 20 degree viewing angle was also too small. Your suggestion of searching for an AC LED <https://www.google.com/search?q=%22AC+LED%22+3mm+green> found only one available product that is green in both directions and is exactly what I'm looking for: <https://www.rapidonline.com/pdf/56-2308.pdf> Ebay has some in the UK: <https://www.ebay.com/itm/TruOpto-OSGGD23131E-3mm-Pure-Green-Ac-LED-10000MCD-30/132604396903> $3.50/ea plus shipping from UK is rather expensive. The best I could do is $0.125/ea plus VAT and shipping from UK: <https://www.rapidonline.com/truopto-osggd23131e-3mm-pure-green-ac-led-10000mcd-30--56-2308> However, they only have 18 in stock and do not plan to order more. So, I decided to take the easy way out and simply order some bi-color 3mm LED's and deal with the inevitable confusion when it arrives. <https://www.ebay.com/itm/121748773460> $9/100 pcs. -- 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
Reply by ●October 27, 20182018-10-27
On Wednesday, October 24, 2018 at 4:09:19 PM UTC-7, Jeff Liebermann wrote:> Is there such a thing as a bi-directional LED where each polarity is > the same color?Maybe, using two dies; I'm only sure that there are lighted power buttons for PCs that are polarity-agnostic, do a nice green glow regardless of the connections being switched.. This looks like an option, but it's unobtainium. <https://media.digikey.com/pdf/Data%20Sheets/Lite-On%20PDFs/LTL-10CxJ.pdf> Of course, a bridge rectifier could adapt a variety of lamps, if the budget allows.
Reply by ●October 27, 20182018-10-27
On Saturday, October 27, 2018 at 6:21:12 PM UTC-4, whit3rd wrote:> On Wednesday, October 24, 2018 at 4:09:19 PM UTC-7, Jeff Liebermann wrote: > > Is there such a thing as a bi-directional LED where each polarity is > > the same color? > > Maybe, using two dies; I'm only sure that there are lighted power buttons > for PCs that are polarity-agnostic, do a nice green glow regardless of > the connections being switched.. > > This looks like an option, but it's unobtainium. > <https://media.digikey.com/pdf/Data%20Sheets/Lite-On%20PDFs/LTL-10CxJ.pdf> > > Of course, a bridge rectifier could adapt a variety of lamps, if the budget allows.Mouser has 3000 of the LTL-10CEJ red at $0.33 @ qty 1. Seems the green is obsolete though. Rick C.
Reply by ●October 27, 20182018-10-27
On Saturday, 27 October 2018 18:05:02 UTC+1, Jeff Liebermann wrote:> On 24 Oct 2018 17:15:19 -0700, Winfield Hill > <hill@rowland.harvard.edu> wrote: > > >Jeff Liebermann wrote... > >> > >> Is there such a thing as a bi-directional LED where each > >> polarity is the same color? > > > > https://www.manufacturer.lighting/info/64/ > > > AC LEDs, with two sets of back-to-back LEDs, are available > > for high-voltage high-light-level LED assemblies. For low > > light levels running from AC, people just use a back diode > > and run the LED half-cycle at 60, etc., rather than 120Hz. > > Thanks. Sorry for the delayed reply. > > All the "AC LED" hints under the above description seem to be > 117/220VAC powered and seem to refer to much larger light bulbs and > strips. > > There's very little room for a diode bridge or a 2nd LED. The only > way I could make that happen is to redesign and 3D print a new white > plastic LED frame. The plastic is there to provide voltage isolation > between the solenoid wires and the relay contacts and frame: > <http://www.learnbydestroying.com/jeffl/crud/Omron%20relay.jpg> > I could cram a small SMD bridge along the side of the relay but would > require precision soldering under a microscope, and is too much work. > Similarly, I tried to replace the 3mm LED with two parallel SMD LED's. > It worked, but again required too much work. The typical 20 degree > viewing angle was also too small. > > Your suggestion of searching for an AC LED > <https://www.google.com/search?q=%22AC+LED%22+3mm+green> > found only one available product that is green in both directions and > is exactly what I'm looking for: > <https://www.rapidonline.com/pdf/56-2308.pdf> > Ebay has some in the UK: > <https://www.ebay.com/itm/TruOpto-OSGGD23131E-3mm-Pure-Green-Ac-LED-10000MCD-30/132604396903> > $3.50/ea plus shipping from UK is rather expensive. The best I could > do is $0.125/ea plus VAT and shipping from UK: > <https://www.rapidonline.com/truopto-osggd23131e-3mm-pure-green-ac-led-10000mcd-30--56-2308> > However, they only have 18 in stock and do not plan to order more. > > So, I decided to take the easy way out and simply order some bi-color > 3mm LED's and deal with the inevitable confusion when it arrives. > <https://www.ebay.com/itm/121748773460> > $9/100 pcs.that's a 5mm led isn't it. Could you jam 2x 3mm leds in there? NT
