Alarm system transformer + power supply (would both go bad at once?)

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Dead alarm system troubleshooting advice requested ...
http://farm6.staticflickr.com/5540/10989825326_f3fcb528ab_o.gif
Yesterday, I had been messing with the main breakers, and accidentally shut the main 200A breaker without turning off the power generator switch; so the Generac kicked in; and I heard the alarm system in the garage vehemently complaining with persistent loud beeps.
I immediately reset everything, and I thought it was all ok.
Then, today, the alarm system sounded three loud long beeps, and went totally dead.
http://farm6.staticflickr.com/5522/10989723005_3ee48ee609_o.gif
Troubleshooting with my Fluke after removing the alarm system external wires shows the external ELK-TRG21640 16.5VAC, 45VA power-supply transformer plugged into an outlet has an open secondary, and when plugged into an extension cord, there is no voltage from any of the three screws on the secondary windings:
http://farm6.staticflickr.com/5527/10989885984_72d64103f6_o.gif
If I thought it was that simple, I'd just replace the transformer; but I wondered why the backup battery didn't run the alarm system. Testing the 12V 5AH battery out of the alarm system shows it's 13.5 volts DC (no load open circuit voltage), which, at least seems OK (I don't know how to load it though):
http://farm4.staticflickr.com/3731/10989888274_6ed9f59f77_o.gif
So, two things must be wrong: 1. The ELK AC transformer secondary opened up suddenly 2. Maybe the power supply inside the alarm system box went bad suddenly
http://farm4.staticflickr.com/3751/10989824356_41ff0ca903_o.gif
Do you think shutting the breaker without turning off the generator could have blown the alarm system?
Any other troubleshooting suggestions?
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On Friday, November 22, 2013 1:35:28 AM UTC-5, Danny D'Amico wrote:

It shouldn't, but you'll never know if your experimentation somehow caused it or if it was just a coincidence. There is no question that home generators of various types have been known to screw up some electronic equipment at times.

I assume you checked for any low voltage fuses?
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On Fri, 22 Nov 2013 06:09:02 -0800 (PST), " snipped-for-privacy@optonline.net"

Also, depending on where fuses are located, the power supply failing (for example, a shorted capacitor or diode) could have taken out the transformer secondary. So, it isn't necessarily a coincidence that both failed at once.
Pat
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On 11/22/2013 6:09 AM, snipped-for-privacy@optonline.net wrote:

Transformers often have thermal fuses inside them. But the ones I've replaced were in the primary. And since you confirmed secondary, probably not your problem. Might be worth a look tho.
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On Fri, 22 Nov 2013 06:37:01 -0800, mike wrote:

This is a pretty common transformer based on a quick google search for the ELK TRG1640 (16.5VAC, 45VA).
They have a green LED, which no longer lights in my busted transformer.
Interestingly, this PDF specification sheet intimates the secondary is "auto fused" (whatever that means): http://www.elkproducts.com/_literature_63744/P1216,TRG1640,TRG2440_Data_Sheet
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snipped-for-privacy@optonline.net wrote:

Hi, Just start with replacing the x-former and battery. I strongly suspect battery is no good. When you check the voltage did you remove a lead from battery terminal since you mentioned no load voltage. Your battery is not holding charge so when x-former quit, it couldn't supply the necessary juice.
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On 11/22/2013 10:12 AM, Tony Hwang wrote:

Look at the picture of the module between the battery and power terminals. It's a battery saver module designed to keep the battery from being completely discharged. Look closely at the blue electrolytic capacitor on the module circuit board. It looks swollen and electrolytic capacitors can dry out and become a short circuit, especially if they're 22 years old. ^_^
TDD
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On Friday, November 22, 2013 11:12:21 AM UTC-5, Tony Hwang wrote:

It's easy enough to verify that the battery is or isn't the problem. He's got 13.5V on the battery with no load. That doesnt' sound like a bad battery to me. All he has to do is measure the voltage with it connected to the alarm. If it's 12V and the alarm isn't powering up, then it's not the battery.
When you check the voltage did you remove a lead

Good grief. It's charged to 13.5 volts
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LOL! I don't think I have ever seen a battery, showing full charge, be bad. It might not last long, but that is not the issue, here.
Properly maintained, a gel battery will last for a very long time. The problem is the charging circuits really don't maintain and tend to die without notice. You will find this in exit signs with emergency lighting. Everyone I have ever checked had a dead battery along with a dead charging board. Yanked and LED replacement installed with better electronics.
Cost more, but it works. Now, convincing the facility maintenance manager to have them self, or someone, do an annual check on that little test button on the buggers, instead of waiting for a power failure to clue them in on the fact that the thing does not work.
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On Saturday, November 23, 2013 1:01:04 AM UTC-5, Nightcrawler® wrote:

Exactly. And even if it is bad, you don't need to buy a new one, as has been suggested to find out. Danny has a meter. If he hooks it up and it still measures around 12V and the alarm doesn't power up, it's *not* the battery. Also, if the alarm is totally screwed, there is no sense in wasting money on a new battery. A new panel typically comes with a battery included.
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On Fri, 22 Nov 2013 09:12:21 -0700, Tony Hwang wrote:

I understand. The battery is probably at least 2 years old. And the transformer is clearly shot.

That's the funny thing. I would have expected the battery to run the system until it was dead; but the open-circuit voltage was good.

Yes. I checked the battery voltage with nothing attached, just as I had checked the transformer resistance, also with all wires removed.
I also powered the transformer with an extension cord, and checked the outputs, which were zero.

It might be that the battery was actually bad, but, it had enough juice to run the DMM (which doesn't take all that much current).
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On Fri, 22 Nov 2013 10:58:18 -0600, The Daring Dufas wrote:

The electrolytic capacitor did look a little schmushed! It was pressed up against the transister, so I bent it away from the transistor.
BTW, I just noticed the power supply has a "lifetime limited warranty". http://www.elkproducts.com/product-catalog/elk-trg1640-ac-transformer-16-5-vac-45-va-auto-resetting-grounding-prong-and-terminal
I wonder what that means...
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On 11/22/2013 6:11 PM, Danny D'Amico wrote:

The link is to the newer transformers which have PTC "Positive Temperature Coefficient" fuses. As I recall, that type of fuse is a conductive matrix inside a polymer which expands when heated thus raising the resistance of the fuse to that of a high value resistor. As long as the power is on, there is enough enough current flowing through it to keep it warm enough to present a high resistance. When the current flow through it ceases, the fuse cools off and the resistance drops to a low value until the current exceeds it's designed cut off. Any gear with a PTC fuse will shut down until power is removed allowing the fuse to reset. The old transformer you have has a short piece of tiny wire attached in series to the secondary winding of the transformer and it will melt when the current exceeds that which the tiny wire will handle. It's a safety device to prevent overheating of the transformer and the possibility of a fire. That module between the battery and power leads is a battery saver which cuts the connection to the battery when the voltage drops to a predetermined value which the battery will not recover from if it's completely drained. I believe the blue electrolytic capacitor is defective and the module may not work. It could have presented a short circuit to the power transformer which popped the fusible link. It's been a while since I did a lot of work in the alarm industry but the basics haven't changed very much. There a guy who posts here and in several groups who currently works in the alarm business and I could find him and try to get him to respond to your post. ^_^
TDD
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I was thinking about this and was wondering if the transformer was on its way out, anyway, or if the generator presented an open neutral situation on start-up. Maybe a combination of the two.
I had a messenger cable break at one of my old homes, and without actually getting up on the roof and inspecting it, one would have never noticed the break. Anyway, pretty much every non-protected wall-wart in the house fried. Thankfully, the important ones were on a UPS. I could care less about the phone and the foo foo crap in the bathroom. :-)
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On Fri, 22 Nov 2013 21:19:06 -0600, The Daring Dufas wrote:

Ah. I see. Mine is at least ten (maybe twenty?) years older.

That would explain why it blew once, and then died. I did smell burnt plastic; but the garage doors were open so it dissipated too quickly for me to identify from where. It was only a while later, after testing it, that I realized the power transformer had blown.

I guess the good news is that the newer transformer will survive that, if when I put it in, that's the case of the shorted power circuit.
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On Saturday, November 23, 2013 11:44:47 AM UTC-5, Danny D'Amico wrote:

Don't screw around with testing it with a new transformer, buying a transformer, battery, etc. You have a battery that reads 13.5 volts without a load. Put it in the alarm. If the alarm doesn't power up and the battery still reads around 12V, you know there is more wrong than the transformer. Then you have two choices. Either find out what's wrong with the alarm and fix it, or buy a new panel. And if you wind up having to buy a new panel, they typically come with a battery and charger.
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On 11/23/2013 10:44 AM, Danny D'Amico wrote:

That module attached between the battery and the panel is a battery saver module. The panel will work without it and I believe it's shorted out and is what blew the transformer. If you or one of your friends can repair circuit boards, get him/her/it to take a look at it because it's a fairly simple circuit. I would remove the module and hook the panel's power leads directly to the battery. Hopefully, the battery charging circuit on the panel's circuit board is not damaged. ^_^
TDD
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On Sat, 23 Nov 2013 12:29:02 -0600, The Daring Dufas wrote:

You are correct! I had thought it was a "power supply" but it's not. A sticker says it's a "D135A low battery disconnect", which is apparently supposed to be sticky-taped to the top of the battery.
Googling, it's a 9.5 volt cutoff (as you said, to save the battery from a deep discharge). I'm surprised you could tell that from where you sit, because I only just realized that myself now.

You seem to be familiar with this stuff but I must ask:
What is the "it" in the sentence above? The battery? Or the low-battery protection board?

Before I do this, may I clarify the suggestion?
Should I remove the D135A low-battery protection board, and then, connect the battery directly to the black and red power leads of the Radionics D2212B (LT) circuit board?
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On 11/23/2013 1:59 PM, Danny D'Amico wrote:

"It" is the low battery disconnect. Connect the power leads you remove from the D135A directly to the battery to see if your system operates. I haven't worked exclusively in the alarm industry for many years but I would get into alarms from time to time. Your alarm system is at least 21 years old. The date code on the small round bridge rectifier on the circuit board looks like it was manufactured in 1992. ^_^
TDD
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On Sat, 23 Nov 2013 16:23:09 -0600, The Daring Dufas wrote:

That is the most direct test I could have run, so, following your advice, I took the power and ground leads coming out of the alarm system board and plugged them directly into the battery, which was at 13.5 volts.
The current draw was 98 ma.
But the only thing that happened was the alarm system made a single beeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeep that lasted the entire time that the battery was connected.
I tried this, multiple times, for no longer than the time it took to snap this picture though, as I didn't want to ruin anything further.
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