How long b4 a dash cam drains the car battery?

OmoP

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First time poster here...

I would like first to give thanks to several members on this forum including @Sunny @jokiin @Dashmellow @niko @kuoh & many more. I don't know much about dash cams but after watching several YouT vidz & going thru threads on this forum, I feel much more informed.

Upon comparing several dash cams on Amazon & going through reviews, I was sold on the Rexing V1 2.7" after reading @Sunny review. I ordered a few days ago & hard wired it this weekend.

As my vehicle is equipped w/ a sunroof, I used a DMM to find the constant, switched & ground wire on the harness in the overhead console & currently have the dash cam tapped off the switched 12V wire via a dash cam wiring kit. Furthermore, I made sure to add a 2A in line fuse too.

But I am now looking into having the dash cam on 24/7 (basically tapping into the constant wire). Ofcourse, I am worried about the car battery drain & considered adding a power bank btw the wiring kit & the dash cam but after taking a look at this thread, I saw that simultaneously charging & discharging a LiPo battery is not only a bad idea but also that most power packs disable the outputs when being charged. :(

Btw, I am not interested in the "motion activation" nor "parking mode" functions of the dash cam as I find those features in reality to be unreliable & expect a lot of false positives. I just want the cam to be on at all times but am worried about battery drain.

When asked on Amazon, the seller (Rexing) says the V1 has an avg power consumption of 3W 450mA w/ a max of 3.5W 650mA. I hav it installed in a Camry & the hardwiring kit I got says it has a "LOW voltage protection parameter." Does that mean it is safe to wire it to the constant wire?

Also, based on the dash cam's current usage above, can some1 give an estimate (showing the math pls) of how long it would take my dash cam (worst case) to put my car battery in an unhealthy state?

For the record, I go no longer than 5 days w/ out driving my vehicle & moreover I have ceramic tint on all my windows. In addition to that, I live in an Apt complex w/ a parking deck & so my vehicle doesn't get exposed to sunlight for extended periods of time.

Thnx in advance for the help!





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jokiin

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Too many ¯\_(ツ)_/¯
5 days powered should be long enough to leave you with a flat battery, if that camera has an internal battery you would do better to just use it as intended wired to accessories though as you'll shorten the life of the camera considerably
 

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parking mode reliability depends on the camera. the one in my blacksys cf-100 works great, and doesn't overwrite the card too aggressively. that's another issue running 24/7 - a 64gb card will start overwriting the oldest file after approx 8-9 hours depending on quality settings you may choose. whereas with parking mode on my cf-100, it doesn't overwrite that quickly because it doesn't keep every moment of parking video - only ones where it thinks it sees something. on top of that, most cards aren't made for 24/7 recording, and the card will fail in short order (maybe a couple months if you're lucky), leaving you with NO recordings.

i have a battery drain preventer on mine (see the cf-100 link in my signature) to keep it from killing the car battery. the longest it's ever run is about 1.5 days before the BDP cut off power to the camera, so that i'd still have enough juice to start the car.
 
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petepete

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Temperature effects 12v battery capacity so no one can answer you with a calculation.

Point of fact capacity can be down 40% on a brand new battery at freezing point compared to its 25 degree centigrade quoted capacity and plenty more on an ageing battery.
 

Gibson99

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Temperature effects 12v battery capacity so no one can answer you with a calculation.

Point of fact capacity can be down 40% on a brand new battery at freezing point compared to its 25 degree centigrade quoted capacity and plenty more on an ageing battery.
very good point. in the US they label batteries with CA (Cranking Amps) and CCA (Cold Cranking Amps). CA is measured at like 32f and CCA at 0f (yes, 32 below freezing). CCA is always significantly lower than CA because batteries (of all types, not just car batteries) always perform worse in cold weather. it's why batteries are so expensive in spacecraft - because they have completely different chemistry and construction to handle the cold.

http://www.optimabatteries.com/en-us/experience/power-source/what-does-cold-cranking-amps-cca-mean/
 
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OmoP

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@jokiin @Gibson99 @petepete

Thnx for the advice guys but I was able to come up w/ a solution that I feel meets my needs.

I decided to wire my Rexing V1 dash cam to a constant 12V wire BUT I added a switch in btw the the constant wire & the dash cam. Although some might find this counter intuitive (since a dash cam is supposed to be a set up and go device), it is a PERFECT solution for me as it allows me to leave the dash cam on during the day -- such as when I head to the store -- as the dash cam will be recording while am away from my vehicle -- and I can simply turn it off w/ the flick of a switch.

Unfortunately, the switch I got is slightly to big for my dash slot so I intend on using a power drill w/ a sander or sth to shave off the grooves in the dash hole.
 

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petepete

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@jokiin @Gibson99 @petepete

Thnx for the advice guys but I was able to come up w/ a solution that I feel meets my needs.

I decided to wire my Rexing V1 dash cam to a constant 12V wire BUT I added a switch in btw the the constant wire & the dash cam. Although some might find this counter intuitive (since a dash cam is supposed to be a set up and go device), it is a PERFECT solution for me as it allows me to leave the dash cam on during the day -- such as when I head to the store or mall the dash cam will be recording while am away from my vehicle -- and I can simply turn it off w/ the flick of a switch. :D

Unfortunately, the switch I got is slightly to big for my dash slot so I intend on using a my power drill w/ a sander or sth to shave off the grooves in the dash hole.

That's just the end to a strange day for me...

In interview today as a professional kitchen fitter with 12 years experience I was asked if I could drill a hole in a kitchen door to take a hinge and told they had a template for doing so.... unbelievable !!!

And now you are fitting switches when the camera has one on it ... unbelievable !!!!

I half expect the lottery prize guy to knock on my door tonight ... unbelievable !!!
 

DocHudson

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@jokiin @Gibson99 @petepete

Thnx for the advice guys but I was able to come up w/ a solution that I feel meets my needs.

I decided to wire my Rexing V1 dash cam to a constant 12V wire BUT I added a switch in btw the the constant wire & the dash cam. Although some might find this counter intuitive (since a dash cam is supposed to be a set up and go device), it is a PERFECT solution for me as it allows me to leave the dash cam on during the day -- such as when I head to the store or mall the dash cam will be recording while am away from my vehicle -- and I can simply turn it off w/ the flick of a switch. :D

.
Do you mind a doing detailed write-up for noobs like me? To avoid power drain or shorting anything, wasn't planning to hardwire but this looks perfect for my needs too.
 

jokiin

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Too many ¯\_(ツ)_/¯
I decided to wire my Rexing V1 dash cam to a constant 12V wire BUT I added a switch in btw the the constant wire & the dash cam. Although some might find this counter intuitive (since a dash cam is supposed to be a set up and go device), it is a PERFECT solution for me as it allows me to leave the dash cam on during the day -- such as when I head to the store or mall the dash cam will be recording while am away from my vehicle -- and I can simply turn it off w/ the flick of a switch. :D.
another option rather than just having an on/off switch that you could quite easily forget to turn on is to have a 3 pole switch wired to accessories and permanent power, so you'd either be ignition switched or constantly on depending on your selection, but never off
 
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OmoP

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And now you are fitting switches when the camera has one on it ... unbelievable !!!!
So let me get this straight...

In your opinion, it makes more sense to connect my dash cam to my constant wire (thus it will run 24/7) instead of adding an easy to reach switch that will be flush w/ the OEM panel switch on the left side of my steering wheel...

And you think it would be MORE wise to always have to reach behind my rearview mirror to turn it off (btw I would have to unplug it as I don't trust that the power button would keep it off since it still detects a 12V current) and thus need to reach AGAIN behind my mirror to turn it on whenever I wish to turn it on again.

Also, the Rexing dash cam doesn't have this "switch" you speak off. Only a power push button.

@Gibson99 do u agree w/ their statement also?
 
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OmoP

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another option rather than just having an on/off switch that you could quite easily forget to turn on is to have a 3 pole switch wired to accessories and permanent power, so you'd either be ignition switched or constantly on depending on your selection, but never off
Thxn for the advice. But I am now confident that I do not wish to have the dash cam ever in "switched" mode as I like the idea of having it running when I go into the store for groceries or sth & being able able to turn if off at will.

But you're right that it is easy to forget to turn it on but looking at just how big & cool that switch is, I probably won't forget.

Also, am no Electrical Eng. and had to look up a lot of info b4 wiring this switch myself but doesn't "3 pole" mean the switch would control three circuits? In that case, what exactly would those three circuits be?

Or did you mean Singe Pole Triple Throw?
 

jokiin

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Too many ¯\_(ツ)_/¯
3 pole is just 2 inputs, 1 output, (SPDT) an accessory and a permanent feed would mean it would only ever be one or the other, given the way your switch lights up I don't you'll forget but some people might prefer something a bit more discrete, something like this perhaps http://www.ebay.com.au/itm/321369562260
 
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OmoP

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3 pole is just 2 inputs, 1 output, (SPDT) an accessory and a permanent feed would mean it would only ever be one or the other, given the way your switch lights up I don't you'll forget but some people might prefer something a bit more discrete, something like this perhaps http://www.ebay.com.au/itm/321369562260
According to this article what your referring too is a SPDT switch. The article says & I quote, "SPDTs are great for selecting between two power sources, swapping inputs, or whatever it is you do with two circuits trying to go one place. Most simple slide switches are of the SPDT variety. SPDT switches should usually have three terminals. (Sidenote: in a pinch an SPDT can actually be made into an SPST by just leaving one of the switch throws unconnected)."

And I would have gone for a switch like what you linked above but was lead to believe that this "zombie" switch I bought would be a direct fit into my OEM rocker switch hole (the item description say it is supposed to fit most modern cars)
 
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jokiin

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yes single pole, double throw, just lets you select between two power sources, permanent or switched but never off, the worst you could do is leave the cam running, if just a simple on/off there's a chance of leaving it off and you just know that one time you forgot would be the one time you needed it most :)

not saying your option isn't suitable for you, just mentioning this for others
 
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OmoP

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yes single pole, double throw, just lets you select between two power sources, permanent or switched but never off, the worst you could do is leave the cam running, if just a simple on/off there's a chance of leaving it off and you just know that one time you forgot would be the one time you needed it most :)

not saying your option isn't suitable for you, just mentioning this for others
Thnx for the recommendation.

I just ordered a set of SPDT switches off Amazon (much faster than eBay w/ Prime shipping) that should be arriving tomorrow. You make a good case for having the switch toggle btw switched & constant power vs. between on & off.
 
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** Update 10/7/15 **

I would like to thank @jokiin for the SPDT switch idea.

I successfully replaced my initial SPST switch w/ a SPDT switch last night & now I have a much more discrete switch that toggles the dash cam's power input btw a switched & constant source. This way, I can always count on the dash cam being on (vs. the on & off option of my last SPST switch idea) in case of an incident.

I did have to drill a hole into one of the "blank" dash mount sockets but the install turned out very clean looking. :D

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