DMP XR-20 - NO DC

I don't know what you've already tried so here's what first comes to mind.

Bad rectifier? or the battery leads were reversed? ( I don't know how/ if they have breaker for reversed leads) If the transformer got a blast etc............. might have taken out the rectifier. If there's no breaker .... settable or self resetting ....... are there any permanent fuses on the board or on the back of the board?

If you can find the rectifier, measure the DC output. It's going to be unregulated so if you have an analog meter, it'll allow you to better guess at the average output. If it is the rectifier you can usually replace it pretty easily or substitute four healthy diodes. Alarm mfg's pretty much use compressed mud for components. Don't know how much you get into circuitry but sometimes the rectifier is good but the regulation components are bad. Capacitor or Zener diode ( if they still use them anymore). If you can find the regulation components, measure on the other side of them to see if you get better DC. If it's all good up to that point then ....

If there are breakers and you get a good DC reading after the rectifier it could be a bad breaker. You'd have to follow the DC out from the rectifier to each of the breakers. Not too easy to do. A partial voltage reading could be indication of a bad (not resetting) breaker. But since more than one voltage output is bad, it doesn't seem like they'd use one breaker for all of them.

Did you check the back of the board for a burned conductor?

If you have another working board, you can use it to get comparison voltage readings to determine where it differs.

Or ..... you could just throw it in the garbage and buy another board .... :-)

Dont forget to power cycle the board some of the newer PTC thermals have to have power turned off before they reset. have this problem with vista 32fb etc bell loop when it shorts you have to power panel all way dawn and back up and it resets

I do have a good pull on the shelf. I would just replace it with new, but I doubt DMP would sell to me anymore. Alternatively I would just swap for a Napco P1632. The system has a couple keypads though so that drives up equipment costs a little.

Ok, I am looking at my good pull right now. No fuses I can find or fusible links on the back like FBII either. It doesn't appear to have a single components bridge rectifier either. Looks like they installed their own diode ring as there are 4 of them on the board near a modestly large capacitor. There is also a small diode in that area. No clue what that would be for except maybe reverse protection. I see a couple components that "might" be circuit breakers. Maybe I'll punch the numbers on it into Google later and see what comes up. Lots and lots of transistors, but only one with a heat sink. Maybe a voltage regulator?

ont-email.me...

Scuse me if I'm being to basic, don't know what you know about regulated power supplies. Here's the most basic regulated power supply schmatic that I could find with a brief description.

The large component on the heat sink is the regulator. It should be a flat three legged semiconductor. If you use the schematic above with a meter with the power off. put your meter in the resistance mode and measure the resistance across each of the bridge diodes. In one direction you should get a direct short. Reverse the meter leads across the diode and you should get about a .7 Ohm reading. Anything different means a bad diode. You will likely get an open across one or more diodes if that's the problem. Take note of which end of the diode has the band on it so you know which way you're putting the leads on it. If it's any other component in the circuit it would be easier to determine what the problem is if you took measurements with the panel powered up. That's too hard to explain here. You might try to google "troubleshooting a regulated power supply". It's pretty simple once you take a look at it for a few minutes.

If it is a diode in the bridge, just about any large diode will do as a replacement. 50 to 100 volt diodes are pretty cheap at RS and overkill for this kind of circuit. The big HOWEVER is ..... If you haven't done any PC board soldering before it's not something that you want to do without some coaching.

There's no fuses on DMP, just auto reseting breakers. What's the transformer output reading when not connected?

I may have a gently used XR20 in stock if you're interested. They don't make the 20 anymore but the will repair it for 40 bucks. I'll send it to repair if you want.

Rob

I said the heck with it and replaced it with a newer Napco panel. More features and modern options available.

@newsfe05.iad...

Took the "easy" way out ....... huh? :-)

Dunno why you always bring up problems like this, then just trash the panel anyway. Send me the board I can use it as replacement after I get it repaird...I'll pay shipping.

Bob just likes to sprinkle the group with little bits of his frustration ..... occasionally ..... every once in a while.

Umm ...... or more often.

I'm guessing it's just the results of a bad fishing day.

LOL.

Fished Yuma Pro Am today. Finished 2nd. Nothing special. Just a local club tournament, but it was a blast. The guy I drew for a partner was the same guy I drew last month when we finished 3rd. At the beginning of the day I told him that I wouldn't count on another strong finish, but I would work at it all day. I figured out a pattern and it worked. If we had capitalized better on our opportunities we had a shot to win. Its our own fault we didn't. Still 2nd is respectable and it pays for the fuel in the boat and truck for the day.

Beats the day my fishing mentor had. He lost a trailer tire on the way in. Only caught two that would measure all day. Lost his trolling motor to a wave that came over the bow and a stripped clamping bolt. Took the steering pedal, plug in mounting plate, and two rods with it. At the end of the day he was so over heated he had to sit down and stop helping with weigh in. Worse he has guide clients booked this week, and won't be able to get his trolling motor replaced and boat fixed in time. I did offer him use of my boat for his clients, but he was pretty down at the end of the day.

My fishing partner referred a custom commercial IT/AV job to me at the end of the day. Sounds like a fun one if I get it.

P.S. Besides weekend tournaments I like to try and get out a couple afternoons a week all summer and into the fall. I also make my own CNC cut bait molds and plastic baits. Our 3 biggest fish and 8 of the 9 fish I boated today came on one of my baits. (I was fishing for size not numbers.) I've also made bait molds for small commercial bait makers that are literally all over the world now.

There's live fish in Yooma?

Hey from now on, since you hate DMP stuff and are really gonna remove it anyway, just send it to me...think of it as a O'Bama TARP bailout subsidy kinda thing.

Now you want me to voluntarily work towards the destruction of the American capitalistic system? Its bad enough that if Obama has his way I'll be better off to quit working and go on the dole rather than try build business and work towards a stronger economy. Now you want me to voluntarily become a socialist?

I don't really hate DMP. They just aren't good enough for me. Maybe the newer stuff is better, but working on old DMP is like working on DSC stuff to me. I always feel like I am their beta tester. I may even fix that bad board myself if I can figure it out to keep it as a spare. I do still have a bunch of them in the field. I think since DMP never lived up to any of their agreements with me I may even take the time to figure out how to crack one. They did tell me there was a crack for them. Well, after many years Sharp finally did pay me back for the charges to my credit card for things I didn't order, but other than that they really never lived up to their word.

The thing is piddling around and tinkering with this stuff doesn't excite me like it used to. I spend my spare tinkering time manufacturing machine parts and injection molds these days. I have retrofit one clapped out CNC machine, redesigned (somewhat) another to get better performance, and I am slowly accumulating parts to retrofit an old proprietary one (Hurco) to modern PC control. That is fun to me these days.

One or two. And some beautiful scenery too. The best part is I don't have to fight traffic for thirty minutes to an hour to get to it after work either. I'll post a slide show for you this evening if I don't go hit one of my lower river areas with a buddy of mine today after work. He's got a mud boat, and we can take that places I can only take my smaller boat when the water is up.

ell$2u60$ snipped-for-privacy@adenine.netfront.net...

David aint in this area any longer, Charlie is but I hardly ever see him.

I'm still partial to DMP, I hate DSC...and I'm getting to old an crotchety to learn anything new other than what I already know.