- Panasonic AG1980P power supply problems - 6 Updates
- Electrical wire size to jump car engine - 4 Updates
| Chuck <ch@dejanews.net>: Apr 10 12:58PM -0500 On Tue, 9 Apr 2019 10:58:05 -0700 (PDT), captainvideo462009@gmail.com wrote: >> Lenny >Chuck >In looking at the schematic I don't see an 18V line. At the output there is a plug. It has outputs of 4.0V, 6.0V, and 14.60V, but nothing marked 18V. Actually, the only zener I see on the board is D1018 and it is off the emitter of Q1006. Could that be the one you're referring to? Also I heard that some parts stores were selling repair kits for these but that was a while ago. Do you know who might still have these available or at least where I could still get the Mosfet? Thanks, Lenny Lenny Though I worked on many of these units, I confused this P Supply with a different Pana supply that had crowbar protection on the 15V line. I would guess that IC1001 is bad and I don't know of any kit that is available. Chuck |
| captainvideo462009@gmail.com: Apr 10 11:18AM -0700 > same problem and I'm not sure what I'm going to do. If anyone can > please help me with this I would sincerely appreciate it. Thanks, > Lenny Chuck, John Del had a novel idea. He said if the mosfet was good and even if the caps had bad esr I might be able to get the supplies to start if i heated them up. I used a heat gun on this one supply and then connected it to the VCR and to my utter amazement the unit came on. I dumped power a few times and each time it started up, so that was a really good tip. The caps all check good but I suppose that I should replace them anyway. Do you have a good source for good, (Nichecon or equiv) 105 degree caps? Thanks, Lenny |
| jurb6006@gmail.com: Apr 10 01:25PM -0700 >"In looking at the schematic I don't see an 18V line. At the output there is a plug. It has outputs of 4.0V, 6.0V, and 14.60V, " He was probably referring to the 14 or whatever line that usually has an 19 VZD for protection. Might even be 12. THAT line is what you test. Silly techs I met checked the 5V, which is not that good an indicator because it is on the feedback loop. As the output goes down in that supply all the others go up. The 12 or whatever volt line is a first thing indicator. BEFORE it blows up. If it is over 14V then you need the 5V caps. Some more complex feedback systems have been used, as well as MOSFETs instead of bipolars, but the 5V as far as I can see FEEDS the opto, which is the main control mechanism. It supplies the drive to the chopper to regulate. When the load increases or the line voltage drops the frequency drops and more current is applied to the primary of the transformer thus increasing output to compensate. The opposite happens when the load decreases or the line voltage increases. You CAN see the action of this system by connecting hot and cold grounds together, using an isolation transformer that is variable and find some sort of dummy load(s). People go "EGAD" when I sat connect hot and cold grounds together but you can do it. You NEED an isolation transformer, and do not connect it to anything else. I have done it many times. But I can go with the scope to both hot and cold sides and actually see just how the feedback works. I found it is much simpler than it seems. One of the MAIN things about those supplies frying out on the absence of secondary filters is on the drain or collector of the output. In the old days it was 4.7uF/250V. I have also seen 10uF. If that cap opens it destroys the chopper. It is not hard to find, follow the cord through the rectifiers and to the primary of the transformer. Look at the "C" or "D" terminal of the chopper and you'll find a lytic. That is critical, no matter what else is going on with it. Nuff for now. Give me more detail and I will give you more detail. I can't give detail when I didn't get any. |
| Lucifer <LuciferMorningstar@bigpond.com>: Apr 11 07:25PM +1000 >>> I have 4 of these that we still use here in the house. Last year we >>> were operating on generator power after a storm, The generator started >>> surging as it began to run out of gas Were you able to switch back to petrol to keep it going? >a different Pana supply that had crowbar protection on the 15V line. I >would guess that IC1001 is bad and I don't know of any kit that is >available. Chuck Sounds like he needs surge protection or a UPS. Some early generators will interact with switch mode power supplies causing them to surge. |
| John-Del <ohger1s@gmail.com>: Apr 11 04:33AM -0700 > > please help me with this I would sincerely appreciate it. Thanks, > > Lenny > Chuck, John Del had a novel idea. He said if the mosfet was good and even if the caps had bad esr I might be able to get the supplies to start if i heated them up. I used a heat gun on this one supply and then connected it to the VCR and to my utter amazement the unit came on. I dumped power a few times and each time it started up, so that was a really good tip. The caps all check good but I suppose that I should replace them anyway. They'll read much better when hot so it's best to check them when cold. In any case, checking ESR in circuit isn't foolproof. Today we run into low ESR smd low value caps bypassing high value electros and fooling the ESR meter. Since these supplies run 24/7/365 and are stuffed into an enclosed and tightly spaced can, they're well beyond any reasonable expectation of hours. Change every electo in the can and you should be good for another 10 years. |
| Chuck <ch@dejanews.net>: Apr 11 11:10AM -0500 On Wed, 10 Apr 2019 11:18:33 -0700 (PDT), captainvideo462009@gmail.com wrote: >> Lenny >Chuck, John Del had a novel idea. He said if the mosfet was good and even if the caps had bad esr I might be able to get the supplies to start if i heated them up. I used a heat gun on this one supply and then connected it to the VCR and to my utter amazement the unit came on. I dumped power a few times and each time it started up, so that was a really good tip. The caps all check good but I suppose that I should replace them anyway. Do you have a good source for good, >(Nichecon or equiv) 105 degree caps? Thanks, Lenny Mouser Electronics. They also carry Panasonic 105C caps which I prefer. https://www.mouser.com/?gclid=CjwKCAjwy7vlBRACEiwAZvdx9ktqhBZeToY8xAakH1D_8EGpj_EkO3NURTkAVIRR_2dI9T7_RgfMrxoCG0UQAvD_BwE John's idea does work on this supply. The one I was thinking of would have had the shorted 18V zener so it wouldn't start. Good luck with the other supplies. As JUR6006 says, the 5V line caps are definitely bad. With an ESR meter, you'll probably find others. Good luck. Chuck |
| Stephen Wolstenholme <steve@easynn.com>: Apr 11 11:40AM +0100 >You can also get enough charge into a car battery with a set of AA cells, according to youtube. That depends on the size of the "set" -- http://www.npsnn.com |
| tabbypurr@gmail.com: Apr 11 03:59AM -0700 On Thursday, 11 April 2019 11:40:23 UTC+1, Stephen Wolstenholme wrote: > On Wed, 10 Apr 2019 07:52:16 -0700 (PDT), tabbypurr wrote: > >You can also get enough charge into a car battery with a set of AA cells, according to youtube. > That depends on the size of the "set" lol |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Apr 11 04:32AM -0700 On Thursday, April 11, 2019 at 6:40:23 AM UTC-4, Stephen Wolstenholme wrote: > That depends on the size of the "set" Let's look at that. A typical alkaline battery runs about 2.5 AH at 1.6 VDC or so. Meaning it will make about 4 watts for about an hour - a measure of the actual current it can produce. The typical starter on a 2.0 liter gasoline automotive engine draws about 200 A at start. More if the engine is cold, more if a diesel, more if worn and so forth, but for the purposes of this discussion, figure 200 A at 13.6 VDC. That comes to 2,720 watts for about three seconds - average crank time for a well-tuned, cold engine. Now, work the math and figure the number of AA batteries required to put that much charge into a battery for the requisite period. Now, figure that the battery failed for a reason. What does a sulphated cell look like? It can be done. But the cost, trouble and time require, as well as the likelihood of the source materials should be lying around.... Keep that solar panel trickle charger. It will be a much better bet. Peter Wieck Melrose Park, PA |
| etpm@whidbey.com: Apr 11 09:11AM -0700 On Thu, 11 Apr 2019 04:32:29 -0700 (PDT), "pfjw@aol.com" >Keep that solar panel trickle charger. It will be a much better bet. >Peter Wieck >Melrose Park, PA Speaking of solar chargers, I have one charging the 6 volt battery in my Ford 9N tractor. The panel is rated at 7 watts max. Here in the great Pacific Northwest, with the cloudy days and all, The thing is charging at about 17 milliamps. Open circuit voltage is 18 volts. But when the thing is connected the battery voltage measures at 6.5 volts. So I don't think there is any danger of overcharging unless the sun goes nova and really lights the panel up. But I was wondering how to calculate the wattage. is at 18 volts times 17 mA or 6.5 volts at 17 mA? I think I should use the open circuit voltage but I don't know. Eric |
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