Elk power consumption

[mikefamig]

I wouldn't recommend that...think about what happens at the 3-5 year mark on the M1 when the battery fails a self test (in the middle of the night) or as Murphy would dictate, while you are away on vacation.
 
If you put the listed 12 aH on the 212, that'll get you a hypothetical 6 hours fully loaded standby.
 
Lets go around this logically, what sort of standby is the M1 running?
 
There's other ways to skin the cat but you're going to need a RIB, another battery and PS/charger...
 
Have you used the power calc that Elk provides for battery sizing and standby calcs?

I had to do a little reading but I think that I understand what you were saying about the RIB. You are saying to get a backup ps/battery for the 212 ps and have it switch based on the 212 supervisory zone, yes?
 
Mike.

 

[mikefamig]

In all the cases I've done, the M1 typically would run a single 7aH battery and the aux would be 2 of them just due to sheer laziness because the batteries are common commodity items. If the batteries are oversized, then I'd probably look around 10% + the derating factor because I'd be putting them out in the field, most likely unheated.
 
In your case, you'd need to decide what is the real design criteria, either a long standby on the M1, which the 212 is a design flaw, or you go with a reasonable standby on the 212 but under the limit in battery size and then size the M1 off that standby time and then factor in the panel powering down before the 212.

 
I've done the calcs and in it's current configuration the eintrie system draws 2.175 amps.
 
Here is the rundown
 
M1 control  0.14
2 DBH        0.0    passive devices
1 M1KP      0.16
1 M1KP2    0.085
1 M1XIN    0.065
1 M1RFTW
devices that are physically installed in the house draw 0.61 amps and the devices in the garage draw 0.565amps.

 

[mikefamig]

In all the cases I've done, the M1 typically would run a single 7aH battery and the aux would be 2 of them just due to sheer laziness because the batteries are common commodity items. If the batteries are oversized, then I'd probably look around 10% + the derating factor because I'd be putting them out in the field, most likely unheated.
 
In your case, you'd need to decide what is the real design criteria, either a long standby on the M1, which the 212 is a design flaw, or you go with a reasonable standby on the 212 but under the limit in battery size and then size the M1 off that standby time and then factor in the panel powering down before the 212.

I've chosen to go with a reasonable 4 hour standby and I've done the calcs and in it's current configuration the entire system draws 2.175 amps.
 
Here is the rundown
 
M1 control          0.14
2 DBH                0.0    passive devices
1 M1KP              0.16
1 M1KP2            0.085
1 M1XIN            0.065
1 M1XRFTW     0.085
1 M1XOVR        0.33
1 M1TWA          1.0
1 M1XEP           0.3
1 Bosch motion 0.01
 
total                   2.175 amps
 
I broke the load down to the M1 control ps carrying the M1G control, M1XEP, M1KP2 and M1XRFTW totaling 0.61 amps
 
and
 
the p212s carrying the M1TWA, M1XIN, M1OVR, M1KP and Bosch motion detector totaling 1.565 amps.
 
The Elk spreadsheet recommends a 5ah battery for four 4 hour standby on the M1G control and a a 8ah battery for 4 hour standby on the p212s.
 
I plan to use the suggested 8ah battery on the control and the maximum 12ah size battery allowed on the p212s. I'm not asking you to do the arithmetic but can yo confirm that I understand this all correctly and that you believe that this config will work.
 
Mike.
 
PS the power supplies and batteries will all be in the warm house.

 

[Digger]

Only glancing at your numbers quickly but isn't the panel going to be up and running about twice as long as the PS212?  That would cause you to have system troubles etc when the battery backup on the PS212 dies around 7 hours into a blackout.  (8 ah divided by .61= roughly 13 hours and 12ah divided by 1.56 = roughly 7 hours).  Now move the XIN and KP to the panel and your numbers go to (8ah divided by .76 = roughly 10 hours and 12 ah divided by 1.41 = roughly 8.5 hours still not quite there).  If you go with an 18 hr battery on your PS212 (the max it can handle I thought was 18 but correct me if I am wrong) you would get 11,5 hours on the PS212 compared to 13 hours on the panel.  Again still not quite there but just move the KP over to the ELK (8 ah) gives you roughly 10 hours on the panel and almost 13 hours on the PS212 (18 ah). 
 
If you have any fire or CO devices you should have 24 hour battery backup and that's a whole other calculation.
 
Play with the numbers I did this really fast in about 5 minutes as I am running out the door.  Good luck!

 

[mikefamig]

Only glancing at your numbers quickly but isn't the panel going to be up and running about twice as long as the PS212?  That would cause you to have system troubles etc when the battery backup on the PS212 dies around 7 hours into a blackout.  (8 ah divided by .61= roughly 13 hours and 12ah divided by 1.56 = roughly 7 hours).  Now move the XIN and KP to the panel and your numbers go to (8ah divided by .76 = roughly 10 hours and 12 ah divided by 1.41 = roughly 8.5 hours still not quite there).  If you go with an 18 hr battery on your PS212 (the max it can handle I thought was 18 but correct me if I am wrong) you would get 11,5 hours on the PS212 compared to 13 hours on the panel.  Again still not quite there but just move the KP over to the ELK (8 ah) gives you roughly 10 hours on the panel and almost 13 hours on the PS212 (18 ah). 
 
If you have any fire or CO devices you should have 24 hour battery backup and that's a whole other calculation.
 
Play with the numbers I did this really fast in about 5 minutes as I am running out the door.  Good luck!

I am stuck on your first sentence. Why is the panel going to be running twice as long as the p212s?
 
Mike.

 

[Digger]

If you look at the loading of the panel vs the battery in your proposed setup it would run about 13 hours.  The loading of the PS212 vs he battery in your proposed setup would run about 7 hours.  So the panel will be on and you will lose everything on the PS212 after about 7 hours.  That will cause a lot of system troubles etc and beeping keypads. 

 

[drvnbysound]

I'll tell you... if my power is out for more than 7 hours, chances are it was a natural disaster (tornado, hurricane, etc). At that point, I've probably got bigger problems than my alarm system.

 

[Digger]

If your not at home it would be nice to trip the siren and strobes if someone breaks in during a power outage.  If its that long odds are that the cops would be to busy to respond but maybe your neighbors would take a look etc.  I know my neighbors came over last summer when my alarm went off.  I saw them walking around my house (looking at cameras) after I got the text. 
 
The main issue is you don't want troubles and false alarms etc if your aux power supply craps out before the panel. 

 

[mikefamig]

OK I see that I misunderstood the spreadsheet and didn't do the arithmetic. I do understand that an amp/hour is 1amp per hour and as simple as the concept is I didn't do the arithmetic.
 
I can distribute the load as I said above and still use the max 12ah battery on the 1.56amp p212s load yielding 7.7 hours standby but change the 8ah battery on the control to a 4ah battery giving me about 6.5 hour standby. I am also considering removing the ac to dc adapter from the m1xep and powering it from the control which would shorten the standby on the control.
 
Better?
 
Mike.

 

[Digger]

For Burg only that would work fine.  Personally I would want more than 6.5 hours of battery but that is just me. 

 

[drvnbysound]

I have underground utilities, and it's pretty rare that any of my services (power or cable) are out. I've been living in the same place for almost 7 years and I don't know of a time that we've been without power for more than ~45 minutes. Understand that I also live in a region that's very prone to hurricane and tropical storm activity.
 
It may likely have to do with the fact that I'm about 3 blocks away from (2) schools, one of which doubles as a hurricane shelter

 

[mikefamig]

For Burg only that would work fine.  Personally I would want more than 6.5 hours of battery but that is just me. 

 
Well if I throw out the m1twa which uses 1amp I get the p212s down to 0.565 and get over 20 hours of standby with the 12ah battery. Then put my 8ah on the control giving about 13 hours standby.
 
That is looking like a pretty good idea at this point. The advantages of that m1twa just isn't worth all of the resources that it uses.
 
Mike.

 

[drvnbysound]

Mike, something else to look at is the actual draw of the TWA. Yes, I believe it is rated at the 1A that you suggest, but I believe that's MAX output. Which begs the question, what loads do you have on each of the channels, and how high do you have the volumes of each adjusted?
 
In the last installation that I used a TWA, I was only connecting (3) SP12F's, which are 32-ohm - one to each zone and the volume adjustment for each was almost at the minimum level. I was able to power it over the provided ribbon cable and didn't require the separate power connection.

 

[drvnbysound]

Here's a note from the installation guide about powering the TWA:
 
"Connect the 12 conductor cable from connector J16 on the Control to connector J4 on the M1TWA. The RED and Black wires (+12V & Neg) wires are the primary power for the M1TWA.
 
NOTE: It may be required to connect a separate "supplimental" power source to the two (2) power input screw terminals on the M1TWA, depending on the number of speakers connected and the existing load on the control panel."

 

[mikefamig]

Mike, something else to look at is the actual draw of the TWA. Yes, I believe it is rated at the 1A that you suggest, but I believe that's MAX output. Which begs the question, what loads do you have on each of the channels, and how high do you have the volumes of each adjusted?
 
In the last installation that I used a TWA, I was only connecting (3) SP12F's, which are 32-ohm - one to each zone and the volume adjustment for each was almost at the minimum level. I was actually able to power it over the provided cable/connection and didn't require the separate power connection.

Yes I understand that and I was running it on the control ps which is only a 1 amp supply along with a kp and wireless adapter and the twa load factor is a number that will have to be fudged in the end. In reality there is no audio output at all  when the system is sitting whether armed or not.
 
I am just not impressed with the twa for my purposes. It is a resource hog. The twa uses five outputs - three for audio output and two for listen-in and recently I learned that there is no programmer API for the listen-in and you have to call the system on the telephone if you want to listen in to a microphone. I had envisioned being able to listen in from my iphone or ipad. The twa is not everything that I expected it to be - I should have read the specs closer before buying it.
 
I have no regrets though. I designed my system with no previous experience in security/automation and I did a pretty good job of making my parts list. I have one extra battery and the twa if I decide not to use it but otherwise I have used everything from the original design. Things have been moved around as I just moved the p212s and it's battery from the 14" can in the cold garage into the 28" box in the house but I've stuck pretty closely to the original plan.
 
This is in no small part due to all of the help that I've gotten here. There are a few things that I definitely would not have thought of on my own like putting the 14" box that came with the kit in the garage and buying a larger 28" box for the house (which made it possible to bring the 212s indoors), and buying a second power supply and the fact that the kp has two more f keys than than the kp2 and so on and so on. The devil is in the details.
 
If anyone is planning a new system I highly recommend that you list your proposed system in the security forum and these guys will pick it apart for you.
 
Mike.