Elk M1 strange ac/battery problem

[Del91574]

I'd run it by the guys at Elk, but I can't see any reason why longer battery leads couldn't be used if the AWG was increased and the same faston style terminals were used, as long as appropriate separations between nonpower limited wiring (battery leads) and power limited wiring (field wiring) were maintained.

Might slightly change the UL listing, but it's pretty common in the fire alarm world to have a separate battery can/bucket with the associated wiring run in conduit to the panel.

I can't say I've seen the bending on the battery shelves you've reported, however, and I'm using at least 7-8 Ah batteries in them in Elk enclosures, so I'm not sure if you're putting them into a different manufacturer's enclosure.

 

[video321]

Since we're talking about failing batteries...

I have a 2nd Elk battery ready to be installed (same as current one that is 1 yr. old) in parallel to increase run times. A situation like Work's is what I dread because the I assume the system would see enough amperage off the 2nd battery to be happy even if the 1st battery was failing, swelling, and leaking. Besides a visual inspection is there anything I can do to get notification of a single battery failure? Should I worry about putting something between them on the hot line to isolate them?

 

[Del91574]

The panel isn't going to be looking at the amperage, the dynamic test consists (essentially) of the panel killing the AC input of the charging circuit, running the system off only the battery for a period of time and when the panel sees the voltage drop below it's threshold, a LB signal develops.

First, I would install the batteries as a unit pair, same batch or similar manufacturing time(s) otherwise it is possible for a push-pull situation to happen as they age, since they are not of the same base values within a normal manufacturing tolerance. Most batteries lose about 10% of their initial ratings within that year, from what I've experienced testing them routinely.

The one thing I have seen that addresses or mitigates battery failure is routine inspection and testing, nothing else. I'd recommend, although it may not be the most cost efficient method, compared to 2 7 or 8 Ah batteries in parallel, would be to install a larger singular battery so the panel itself can supervise it (somewhat) within it's capabilities. Also, verifying the charging current(s) and voltages are also key, as a battery that is constantly overcharged will tend to fail early.

The one other item I can toss out there is buy a halfway decent battery, however failures that result in splitting, swelling, leaking, etc. are somewhat common on aged or overcharged batteries.

 

[video321]

Yes, DEL, you're right - voltage. Must of had amperage on my mind since I was thinking about run times. But what I didn't think about until I read your post is if I have 1 good & 1 bad battery the voltage should read somewhere between the two and if it does drop too low then signal a low battery condition.

I would have liked to add a single large battery, but it wouldn't fit in the panel and because of the age difference I planned on changing them both in 3 years regardless of how they test - the original battery would be just over 4 yrs. old at that point.

 

[Del91574]

I'm mid battery replacement at one of our larger sites for a planned "black start" of the site. We're looking at something like 200+ batteries, with the bulk being 26 Ah or larger, so unfortunately, I've had to do a lot of battery inspecting and testing and I've seen a lot of issues come to light, including batteries that were just replaced within the last quarter. Another site has 2000+ access control doors, so figure 3 power supplies per 8 doors (1 12V for the REX's and a 12 and 24V for the locks) with at least 5 batteries per 8 door bundle, with the majority of these supplies not having batteries changed or maintained over the last 2-5 years.

Unless my hand was forced, I'd prefer to see a matched set of batteries or "new" being installed at the same time, especially given what a 7-8 Ah really costs vs the end result. A new 7 or 8 Ah battery is usually within the $10-15 range for a quality unit.

In the case of 2 batteries installed in parallel with a single failing or voltage dropping, I've typically seen the "good" battery start trying to push voltage into the "bad" battery causing the push-pull I described, which ends up killing both batteries, and in the case of being connected to a functioning charging circuit, usually will overload the charger, either (if lucky) causing it to kick off on a thermal or similar or letting out the magic smoke (unlucky).

 

[gatchel]

I just replaced my one battery on my PS212. It was installed May of last year. Nothing is of any quality anymore. The local branch doesn't stock the Elk batteries...Booo....

 

[Del91574]

I remember some article I read somewhere stating in excess of 25%+ (maybe even more) of all consumer products experience QC issues or failures, and while it's unfortunate, premature battery failures are very common in my experience, since we're typically inspecting them in the hundreds in a few intervals, either quarterly, semiannually or annually, depending on the system they're installed in.

I haven't seen any real difference in longevity or better performance in a battery made by Elk or any other manufacturer, so I'd welcome some straight data from any manufacturer stating such.

 

[BaduFamily]

Time for the Bi-Annual revisiting of this topic!
 
I have an M1 which isn't charging the batteries.
 
Ever since installation I have been getting the low battery warning which I attributed to the battery sitting in storage while we were living abroad last year ( during this period the house remodel was finished ). A meter had the battery at just over 12 so I figured perhaps the M1 is very very picky. Finally the wifely one grew tired of pressing the ACK key to quiet the alert beep and asked me to fix it for good, so I ordered a new battery.
 
The new battery voltage was a little higher than the old one so I said to myself " well, it is really picky " and installed it. I ran the system through the battery check to reset it and figured I was done.
 
Low Battery warning.
 
At that point I used the topics here and found that the AC adapter was working fine, the connections to the Elk were fine, but that the voltage to the battery was zero. The Elk can run during the on-load battery test so I know the wiring between the battery and the M1 is good.
 
My dealer is a bit confused by the whole thing so I don't have a resolution / suggestion from them yet. I'm sure they'll come through.
 
So here is my strange question:
 
   can I hook up a motorcycle 12v trickle charger to the batteries _and_ have them connected to the M1 at the same time? And still have a working M1?

 

[Photon]

Take a look at this topic, post #5: http://cocoontech.com/forums/topic/15643-running-the-elk-off-a-deep-cycle-battery-array/?hl=battery

 

[BaduFamily]

thanks Photon, that's interesting.
 
Reading to the end it looks like if I put a fuse inline with the battery I can also have a trickle charger loading the battery _and_ the AC transformer still running.
 
hmm, ok I will have to re-read that again