Spec sheet for Sur-Gard SG-411SM alarm board

[fs483]

Hello,

Not exactly a cabling issue but some of you guys do install alarm systems so I'll give it a try here. I'm trying to trouble shoot my alarm system. This system was installed over 15 years ago. The alarm control board is a Sur-Gard SG-411SM. I'm basically having a problem with the battery backup. I've been replacing batteries about 1 every year. I usually only notice the problem when I turn off the breaker to do maintenance or inspection and then notice the alarm malfunctionning. The battery is a 12V4.0AMP. Everytime I notice the problem I check the voltage on the battery and discover it to be around 8 or 9volts. I always suspected the battery and replaced it without really investigating. Today I had the same problem. Just for fun, I measured the power coming from leads of the panel to the battery and sure enough the voltage was pretty close the one on the battery (with and without battery connected). I'm wondering if the battery is being undercharged. Unfortunately this controller board has everything integrated together (ie loop circuits, battery charge, sirens...). I would like to have a spec sheet for this panel but Sur-Gard doesn't exist anymore, purchased by DSC. Nothing on the Net either. I know also that some systems keep a slightly lower voltage when charging batteries but at 4 volts difference, it seems a bit low. I want to avoid replacing the whole panel which can be done but a lot of work.

 

[phuzzy42]

Is there any reason you can't use an external trickle charger? I'm not an expert by any means so someone who is may tell me otherwise, but if there's no way to repair or replace the alarm board, what other real choice do you have?

Steve Harmon
Greenfield, Indiana

 

[fs483]

I don't know if an external trickle charger would damage the rest of the circuitry since we are applying an external power source to the unit that wasn't designed for this. Most newer alarm systems have separate charger boards and can be easily swapped out. I want to first find out if this controller board is really defective or just that my "cheap" batteries are not good. They do cost 16$ a pop but they are purchased for an over supply electronic store that has been known to sell crappy sub quality stuff. They do however sell alarm equipment. A new panel is around 300$ CAD, which is not too bad and I've already identified all the wires. I would probably need to change the remote access pad. Everything else can be kept... Just didn't want to go through the hassle.

 

[wires]

The best place to check for alarm info is the alt.security.alarms newsgroup.

Using groups.google.com to search alt.security.alarms came up with 178 hits for Sur-Gard.

alt.security.alarms can be quite rough and mean spirited. There are some long running battles there but some consistent posters still point newcomers in the correct direction.

If you have any interest in home automation you might want to look at the latest Elk panels.

 

[jeffbouldin]

After your alarm has been running a few days. Take a digital multimeter and measure the battery voltage on and off the panel. With the battery connected to the panel measure the voltage of the battery with the ac to the alarm disconnected. Report back the different readings and how fast the voltage fell while the ac was off.

If your charging circuit is bad on your panel you will have to replace it and your keypads. If you look deep enough on e-bay you can find a deal.

 

[fs483]

I confirmed my controller is defect. The DC supplied from the panel is about 7 volts. This all actually started when I noticed two of my glass breaking sensor detect faults at the same time. I disconnected them and directly had them connected to the panel but they still detected a malfunction. I never suspected the voltage levels because the motion sensors were working fine. Today I replaced the glass breaking sensors but still the same thing. I then measured the DC supplied voltage and indeed the voltage is wrong. I had also tried replacing the AC transformer but the DC voltage is still below necessary voltage. I shopped around and found the DSC Power632 and the FBI XL-2T. Have any of you used these models ? Which one do you prefer. I mostly see DSC installed but the FBI one has a nice feature that it can dial out to any telephone number if the alarm is triggered.