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Discussion Starter · #1 ·




well I got around to figuring out how to post some pics! sorry it took so long, but here is a side-by-side of the old nasty regulator with crusty potting, overheated, etc; I used some boiling water to remove the old potting from the case so I could reuse it...heated by submerging the case for about 2 minutes or so into boiling water, and applied some pressure, and the guts popped out.



Used hot glue and repotted the Green LED Fix and done! She works great.
 

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Rick,



nice job, is the wire now at the opposite end, and how did you make up the new regulator



thanks
 

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I have quite a few people down I can identify and a few I'm not entirely sure of.



PLEASE include your forum user ID as well as making darn sure your PayPal address that shows up as "Ship to:" is correct.

Far too any people have this incorrect on their account and it's only to you advantage to have it correct, both now and for the future.



My PayPal e-mail address is [email protected]



I always try to reply back to you to verify an address but I've even had a few of those bounce. I'll be darned if I'm going to send them out blindly, were I selling them for a profit I could afford to eat one or two but this is a not for profit deal, 3.50 barely covers my costs so let's get it correct. :)



Complete kit is $6.50 shipped or $9.50 for two kits shipped.



Good job,but if you find that it doesn't regulate as well as you expect it to with temperature variations I've got the true 7807 chips in stock, $3.50 shipped anywhere in the US, contact me if you live elsewhere and I'll figure out what it will cost to mail something.



http://www.innoengr.com/CX500/7V_regulator.html



With shipping to me they cost me about $1.20 each, add the inner bag, cost of a bubble wrap envelope, printing driving, postage etc and you'll see I'm not making any money.



Next time I order I'll get a pile of caps so I can make it into a full kit, I've probably got enough of them in stock to ship out kits in that manner but without an enclosure, just drop me a line. I know the perfect one that would fit the bill but you can even use an old plastic 35mm film can or a pill bottle however I highly recommend some sort of heat sink material on the tab of the IC. With this IC you can mount it directly to any metal, with the 7805 + LED method you can't because the tab will be floating (as best it can) about 2.2V above ground.
 

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Good tip about the boiling water

I never thought to try that

I removed the guts from mine with a scalpel and split the case

If you gave it a decent heatsink it should work well, I have some I've modded been working

for years with no problems

If they get too hot they'll shut down until you power cycle them.

Thats what happened when I tried it.

I fitted heatsink and it was fine until the gauge packed up and my all led alternative

is working pretty well
 

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Discussion Starter · #5 ·
Good job,but if you find that it doesn't regulate as well as you expect it to with temperature variations I've got the true 7807 chips in stock, $2.50 shipped anywhere in the US, contact me if you live elsewhere and I'll figure out what it will cost to mail something.


Marshall,



I am certainly interested in the 7807...I will PM you my info later tonight. If I use the 7807, I shouldnt need the Capacitor correct?



I did NOT put a capacitor in the 7805 fix as it seemed optional. I did however use the Green LED, as well as the original Heat Sink; I did add the heat transfer compound between the 7805 IC Reg & Heat Sink. I wish I took pics of the assembled piece before potting. I did take a pic of the soldered regulator though as I was testing it and will post a couple more pics that might be of interest when I get some time this evening.



I have a circuits guy at work that I am going to have take a look at the original circuit, its components and what not and try to reconstruct it. I would like to have the circuit mapped out and post once its done. I understand the 7807 works fine, and is a great solution to the original, but it would be fun to have the original archived for the purists!
 

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I've got the PM stuff turned off, just hit my profile and e-mail me.



The caps really aren't optional, at a minimum you need 0.1 uF on both input and output pins to ground but I've got plenty of those as well. If you hit the true data sheets on any of the 78xx series they will emphasize these.
 

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I try not to deviate from an IC manufacturer's spec sheets and the caps are specified in every one of them. Being powered by a battery not far away with plenty of load already on the line as well as the current involved to drive the temp gauge circuitry may be enough of a capacitive and resistive load to prevent oscillations in the regulator but I'd never recommend it seeing that the caps are but a few cents apiece if you get them from me or any other good supplier.



There are a lot of inferior ICs out there that are fakes and even RS has recently been accused of selling them. They may work but I tend to stick to brand name only components from a reliable distributor which in your case would be Farnell or Arrow. My other notes are included on that web page I posted earlier and I'm sure that if Rick has a true experienced engineer at work they'll agree with me on this matter.



Kind of hitting us hard, but knockoffs from China once limited to designer stuff are making their way into the system.
 

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It's a good idea to add the caps to prevent oscillation. IF that chip does oscillate it could get pretty nasty, IIRC. As Marshall says, it's doesn't cost that much more.



I remember I had some 7808's lying around, but now that the 7807 is available, I think I would use that instead. I have some 7805's that I can also try. But my OEM regulator is working alright, so if it ain't broke...



Also, what is the current load for that circuit? If it's only driving the temp meter, can be that much. Does it need a heatsink? I can't recall the particulars; too late at night.



Rick, glad to see you are getting the bike fixdt.
 

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It's a good idea to add the caps to prevent oscillation. IF that chip does oscillate it could get pretty nasty, IIRC. As Marshall says, it's doesn't cost that much more.



I remember I had some 7808's lying around, but now that the 7807 is available, I think I would use that instead. I have some 7805's that I can also try. But my OEM regulator is working alright, so if it ain't broke...



Also, what is the current load for that circuit? If it's only driving the temp meter, can be that much. Does it need a heatsink? I can't recall the particulars; too late at night.



Rick, glad to see you are getting the bike fixdt.


Never measured the load yet but I'll bet it's almost 1/2A from what I've seen of the schematic.

Very few 7807's left and no guarantee they'll ever make them again.

Upward of 14.8V going down to 7 at 1/4A - figure it out.
 

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Digi-Key stocks a Rohm version of the 7807 (BA17807T-ND) for about $1.34 Ea. The BA17807t-ND like most of the 78xx family is packaged in a TO-220 package that uses the metal mounting hole as a heat sink. If a hole could be drilled in the original box that would allow a small mounting screw (put the nut on the inside) then the heat sink issue would be solved. The input/output caps keep the IC stable and helps protect the electrical system from Oscillations that could cause odd problems in unexpected places. Its never fun to chase electrical noise issues.



A number of years ago I was involved with a company that built airport beacons. During the construction process a common RTV was used to seal sections of the beacon. When the beacons were later put into production we quickly noticed that the carbon brushes were failing at a much higher rate then some of the older units. The problem was traced to RTV out-gassing. The vapours were destroying the carbon based brushes. There are non/low-out-gassing RTV products available but I am not sure what the cost is. Common RTV is not always good to expose to electronics.
 

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Same IC, but Digi-Key will cost you $9 in shipping.

I can stuff all the parts and ship the IC, heat sink and caps to you with some notes for $6.50 if in the US, $9.50 for two kits.
 

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Same IC, but Digi-Key will cost you $9 in shipping.

I can stuff all the parts into an anti-static bag and ship the IC and caps to you with some notes for around $3 if in the US.


Digi-Key's US postal rate for 3-5 day delivery is about $5.20 but if you can ship the parts for about $3.00 the price sound good to me!
 

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Just drop me a line via e-mail (in my profile) and I'll handle it. Obviously not trying to make any profit here, I'll make up for that some day when I make some up as totally assembled, tested, sealed and then tested again plug in replacements.



The caps you get for the electrolytics may not be as specified, I just wrote it up as "minimum suggested values" so you will likely get equal or better depending on what I've got around. The tiny Kemet 0.1 uF ceramics I love so much I've got plenty of, the electrolytics may be of a larger value but still small enough such that you can put the entire circuit into a tiny box and be done with it. Just don't forget to add a small heat sink to the regulator IC which can be directly mounted to a tiny aluminum case for that matter since the tab of a 7807 is at ground potential.



As mentioned I'll include some assembly notes but the case, wires and solder + iron are up to you.



Digi-Key probably hits me with a higher shipping rate because I usually let them default to UPS, they're way up North from here and whenever I order something I usually like to get a bunch of other things such that the shipping is partially offset. I prefer Mouser myself as they only pass on their discounted UPS rates exactly as they had to pay and if I order from them before 8 PM Central time it's here the next day with simple ground shipping.



About to take off to my girlfriend's house and likely won't be back on until tomorrow if she'll let me take a break. She's got a broken toilet (simple flapper valve replacement from what I remember the last time I saw it) but she's going to get an education in how they work and how to repair them herself. There will be some movie watching involved as well as other things I think we're ready for after knowing each other for around 6 months now.



I'm quite the punisher, she needs to replace an aging Mac in the office area of her house and I'm going to pick out the components then sit back and have her build the box by scratch. I've got an extra KVM switch sitting around so she'll be able to switch between them. I don't mind her laptop too much, runs Win7 64 bit, but her Mac has reached about the end of its useful life as far as software upgrades go.
 

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Marshallf3 – I have two current focus items concerning my GL500I. Resolving a mono shock issue, and building a series pass voltage regulator with a shunt type secondary regulator to guard against the pass device shorting. The goal is to reduce the load on the stator. If you have considered this type of regulator perhaps we could share notes.



Rick – Since this is your 7V regulator thread I would like to keep the focus on the work you have done. I am curious about the hot glue potting. Did you use high temp hot glue? Any idea how close the glue melt temperature is to the 7805's normal running temperature under load?
 

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Marshallf3 – I have two current focus items concerning my GL500I. Resolving a mono shock issue, and building a series pass voltage regulator with a shunt type secondary regulator to guard against the pass device shorting. The goal is to reduce the load on the stator. If you have considered this type of regulator perhaps we could share notes.



Rick – Since this is your 7V regulator thread I would like to keep the focus on the work you have done. I am curious about the hot glue potting. Did you use high temp hot glue? Any idea how close the glue melt temperature is to the 7805's normal running temperature under load?


Good question on the glue. didn't even think about that.



What would the advantage be of the "series pass voltage regulator"?

I am having trouble finding info on how that works and what benefits it would have.

would you like to start a new thread about it?
 

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Good question on the glue. didn't even think about that.



What would the advantage be of the "series pass voltage regulator"?

I am having trouble finding info on how that works and what benefits it would have.

would you like to start a new thread about it?


Panther – Shunt type regulators basically short one or more of the stator's 3 phases to ground to prevent the DC voltage from going above a per-determined point. This means that 100% of the stator's output is being used 100% of the time no matter what the electrical load is. No matter what you disconnect from the DC system, no matter how many lights are replaced by LEDs the stator will run at 100%.



Series pass regulators act more like a valve that open just enough to provide the power needed. This type of regulator will reduce the stator's load on the engine and reduce stator temperature. If anyone is interested in sharing notes on this I would be happy to create a separate thread.
 

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Discussion Starter · #18 ·
It's a good idea to add the caps to prevent oscillation. IF that chip does oscillate it could get pretty nasty, IIRC. As Marshall says, it's doesn't cost that much more.



I remember I had some 7808's lying around, but now that the 7807 is available, I think I would use that instead. I have some 7805's that I can also try. But my OEM regulator is working alright, so if it ain't broke...



Also, what is the current load for that circuit? If it's only driving the temp meter, can be that much. Does it need a heatsink? I can't recall the particulars; too late at night.



Rick, glad to see you are getting the bike fixdt.


Thanks Brian; walking tediously through the carbs at this point; I hope to have some time to play with the bike tonight...all the snow we've had, I might be out plowing all night
not that I am complaining! I do plan to get a proper 7807 from Marshall, caps too, and redo the circuit properly. I just wanted to get something in place to see/confirm that the thermostat was if anything, cycling, and that the bike didn't overheat.
 

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Discussion Starter · #19 ·
Marshallf3 – I have two current focus items concerning my GL500I. Resolving a mono shock issue, and building a series pass voltage regulator with a shunt type secondary regulator to guard against the pass device shorting. The goal is to reduce the load on the stator. If you have considered this type of regulator perhaps we could share notes.



Rick – Since this is your 7V regulator thread I would like to keep the focus on the work you have done. I am curious about the hot glue potting. Did you use high temp hot glue? Any idea how close the glue melt temperature is to the 7805's normal running temperature under load?


Safari,



I know the glue melts at around 250 degrees F; I never considered the nomrmal operating temp under load...probably should have. I did use heat transfer compound and a sheet metal heat sink rivetted to the IC. So far no issues, the glue stays hard, and doesnt show any sign of softening after the bike is warmed up. When I potted the components, I did attach a couple hemastats to the heatsink to pull the heat out as It was potted, then when the glue level got to the hemostats, I removed them, quickly covered the rest, and carfully cooled with water, making sure water was not able to enter the case.



Speaking of hemastats, I also used these by clamping them onto the supply return & ground leads to protect the Regulator when I made my connections to the LED & wires...
 

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Safari,



I know the glue melts at around 250 degrees F; I never considered the normal operating temp under load...probably should have. I did use heat transfer compound and a sheet metal heat sink riveted to the IC. So far no issues, the glue stays hard, and doesn't show any sign of softening after the bike is warmed up. When I potted the components, I did attach a couple hemastats to the heat sink to pull the heat out as It was potted, then when the glue level got to the hemostats, I removed them, quickly covered the rest, and carefully cooled with water, making sure water was not able to enter the case.



Speaking of hemastats, I also used these by clamping them onto the supply return & ground leads to protect the Regulator when I made my connections to the LED & wires...


Is the sheet metal heat sink attached to the metal case so it can shed heat? If not then the heat sink is of little value because it has nothing to pass the heat to. The fins on a heat sink transfer heat from the source to the air. If the air moving over the fins is insufficient to keep things cool then a fan is used to more more air. The 78xx TO-220 IC regulators us the metal tab with a hole in it as a basic heat sink. When these ICs are potted into something that prevents air flow from moving over the tab they can be riveted to the metal case effectively turning the case and anything it's bolted to into a heat sink.



The 78xx regulators have an internal thermal limiting circuit that protects them from over heating. If the temperature goes above a pre-set value the output current will drop until a working temperature is found. The 1A rating for a 78xx can only be achieved with good temperature control. I have seen these little jewels go beyond 1A if the heat sink is really good. We used to blow 7805 and 7812s up just to see how and when they would fry. Some exploded in spectacular ways!
 
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