Battery backup for Safe-T-alert CO/ LP detector

[Josh Robinson]

I just bought the SafeT alert CO/ LP detector for our 1974 13' Boler, one unit, lasts 5 years, great...but it has no battery backup.

So I'm an electrician, I can figure this out right?

Here's my plan;

I bought a Power Sonic PS 12 volt 1.4 Ah sealed lead acid battery, a 12 vdc relay, and a couple 3A/ 1000 V diodes. (All from B&E electronics in Calgary)

I plan to run the main battery through the coil of the relay and in series, run a wire to the terminals of the small battery to maintain its charge. If power fails/ runs out/ is shut off, I want the relay to open so that this mini battery doesn't get eaten by the rest of the RV lights, and maxxfan, but will still power the CO/ LP detector all night.

Questions are:

1: Do I need the diode to isolate the mini battery from powering components in the RV while the main battery is on and charged?

2: Is there any issues with having the same Noco 5x1 genius, 120 v charger, charging 2 batteries in parallel at the same time (when on shore power)? The main battery is a cheap Princess Auto group 24 lead acid deep cycle rv battery.

3. When on solar power only, is there an issue with having the Renogy Rover 20 A charge controller charging 2 batteries in parallel?

All input or suggestions appreciated, as soon as I saw the SafeTalert and that it has no battery backup, this is the first thing I thought of, but I can't find any examples of other people doing this.

[Glenn Baglo]

Originally Posted by Josh Robinson

All input or suggestions appreciated, as soon as I saw the SafeTalert and that it has no battery backup, this is the first thing I thought of, but I can't find any examples of other people doing this.

If your house battery is too low, the SafeTalert will sound an alarm, telling you to charge your battery. If you add a backup battery, it wouldn't alert you.

I'd find another use for that backup battery.


FYI, the date of manufacture isn't important. It's the date of installation of the unit that you need to record. The clock starts when electricity is connected. ( see installation instructions ).

[Josh Robinson]

Originally Posted by Glenn Baglo

If your house battery is too low, the SafeTalert will sound an alarm, telling you to charge your battery. If you add a backup battery, it wouldn't alert you.

I'd find another use for that backup battery.


FYI, the date of manufacture isn't important. It's the date of installation of the unit that you need to record. The clock starts when electricity is connected. ( see installation instructions ).

You say that, but if you look at the reviews of this alarm there are many many people who've found that the EOL- end of life alarm goes off far sooner than 5 years from first install. I energized it yesterday so the clock is ticking either way. If it only lasts 2 years I'll be disappointed but I'll still buy another one as this is the only detector that does both LP and CO.


There is no loss of power alarm. I hooked up the solar panel for the first time yesterday and the Renogy charge controller resets itself which shuts off all power. The alarm just stops working and then once power is restored the green light flashes for roughly 10 minutes while the "heating element" inside charges up. Then it goes solid green and the unit tests as per the manual.


The manual says the unit has "grey out protection" where a short loss of power won't effect the unit. It also says that it will function down to 7 vdc minimum.

[C&G in FL]

Originally Posted by Josh Robinson

You say that, but if you look at the reviews of this alarm there are many many people who've found that the EOL- end of life alarm goes off far sooner than 5 years from first install. I energized it yesterday so the clock is ticking either way. If it only lasts 2 years I'll be disappointed but I'll still buy another one as this is the only detector that does both LP and CO.

LP is heavier than air and sinks. Propane alarms should be located as low as possible. CO alarms should roughly be at the level of your head when sleeping, and as close as possible to where your bed is located. While you may like that it does both LP and CO it may, in reality, provide the best protection.

And if the propane alarm is switched off while the trailer is in storage, the “clock stops ticking.” The 5 year end of life from the first install occurs when the unit is constantly powered. Those are not my words; those are the words of the owner of MTI, the company that manufactures the Safe-T-Alert alarms. My propane alarm is 6 years old, only powered when we are using the trailer, and it is still going strong. I was told the above when I called MTI and asked why the end of life alarm (lights and beeps) hadn’t started.

[CharlesinGA]

I have a flush mount MTI combo LP/CO detector that I used to replace the surface mount LP detector in my Bigfoot. It is on the end of the dinette near the floor. The original surface mount one was apparently ripped off the thin plywood by people propping their heel on the unit as it sticks out a couple of inches.

IN ADDITION, I installed a new battery powered smoke/CO combo detector made by First Alert, the exact same unit that was installed by Bigfoot originally, it is on the ceiling.

Charles

[Josh Robinson]

Well I went ahead and wired it up and I now have a battery backup for the Lp/ CO alarm. It should provide enough backup for a good 8-10 hours. Piece of mind.

Total cost for the battery backup around $30 cad. I did end up needing a diode because the 2 batteries are in parallel and with the loss of power from the main battery the mini battery takes up the whole load too quickly and the relay stays closed, thus power any loads on the system.