Teltonika FMC234 - battery autonomy

bobic9 days ago

I tried getting help on official Teltonika forum, but unfortunately unsuccesfully.

My goal is to track my car if it gets stolen. Since I don't drive my car frequently (sometimes it sits 5 days unpowered), I want tracker with powerful battery.

I have my eyes on Teltonika trackers - FMC234, since it's equipped with 1000 mAh battery.
I will configure it to recharge only when powered on (ignition on)
...and to send me an SMS when car is powered on (as alert someone unauthorized turned it on).

I'm not sure why they suggested me an FMC920 with small battery (170 mAh) since it lasts only few hours?
https://community.teltonika.lt/t/battery-autonomy/15188

Any reccomendations for or against FMC234 ?

Anton Tananaev8 days ago

Do you want to keep sending location even when your car is off? If not, maybe small battery is ok?

bobic8 days ago

No, tracker should report location only while powered on.
In case I'd need a location while powered-off, I will acquire location by SMS command.

I assume small battery wont'be ok, according to the following math (model FMC920, 170mAh battery):

Power consumption
At 12V < 2 mA (Ultra Deep Sleep)
At 12V < 3 mA (Deep Sleep)
At 12V < 8mA (Online Deep Sleep)
At 12V < 12 mA (GPS Sleep)
At 12V < 28 mA (nominal with no load)
At 12V < 2 A Max. (with full Load / Peak)

For unit to receive SMS messages, it needs to be at leat in Online Deep Sleep mode, which consumes 8 mA.
170 mAh / 8mA = 21,25 hours

I keep my vehicle turned off several days. Battery would discharge in the meantime.

Track-trace8 days ago

If your tracker battery is empty then logicly sms wont work since your tracker will switch off. Normally you would just connect the tracker to the car battery so it Will be powered on always.

bobic8 days ago

I thought about that option, but I'm afraid tracker will discharge car battery (discharge just enough not to be able to turn the car on).
I also have dashcam connected - but car battery is protected by hardwire-kit.

I could also connect tracker to hardwire-kit, but for some reason I want to avoid that (too many what-if connections).

Maybe my fear is unjustified and tracker wouldn't affect car battery that much?

Track-trace8 days ago

Why dont you devide the tracker power consumption as you describe here:

needs to be at leat in Online Deep Sleep mode, which consumes 8 mA.
170 mAh / 8mA = 21,25 hours

Do the same math (the track power consumption) with the car battery capacity. Then you will see is nearly zero.

bobic6 days ago

I thought about that! :)
I'm certain that the fully charged car battery will provide long enough power for the tracker.

But... car battery serves also as a component to start the car - there needs to be certain amount of voltage or amperage in the battery to start the car. Despite tracker being low discharger I'm afraid it could discharge car battery just enough not being able to start the car!
And this is the field I'm not familiar with.

Already researching the internet about that (correlation between amperage and voltage on car battery).
If we have any car-electrician here, feel free to share this info :)

Track-trace6 days ago

When you car battery is 60 AH then your tracker could run 7500 hours (very simple calculations can be easy with the use of free co-pilot or chat-gpt).

Do you really think it would make any impact if you do not use the car for one week with so little tracker battery drainage?

Besides the above you could also connect the tracker in a way that it only receives power when you switch on the car ignition (then you will still have a day tracking from the tracker battery after you switch of the ignition).