Dashcam + battery drain ('parking mode') questions

isellparts

Junior Member
Feb 11, 2014
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Hi there,

First post here and was wondering if I could leverage the expertise on the forum for this matter. I am no car guru but have done some research and wanted some opinions.

I was wondering what the long term consequences of keeping my car battery around (if not below) the 12.0v charge is?

I do not drive far enough to keep the charge above this number right now so throughout winter so far, I have been cranking the car with the battery voltage around (generally below) 12.0v.

I am thinking of changing my battery discharge device (currently use a power magic pro which has a cut-off of 12.0v to the battery) to something along the lines of 12.4v (this is the best out there) so I can get some recording done hopefully in the summer when my car is not draining as much through all the winter utilities (heated seats, windshield, heater, etc.).

I know 12.4v is still not optimal but it should be much better than the 12.0v I would think but even at 12.4v, I do not suspect I will get much recording out of 'parking mode' from my dashcam even in the summer... Trying to consider all the trade-offs.

Would appreciate all insights!

Thank you!

Edit - does anyone know how much power these dash cameras usually draw? I have the itronics itb-100hd variant
 
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Kaido

Elite Member & Kitchen Overlord
Feb 14, 2004
49,992
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I'm curious about this too because I was looking at the Power Magic Pro as well. I drive my car pretty much every day so I don't think it'd be too much of an issue.
 

LTC8K6

Lifer
Mar 10, 2004
28,520
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in the summer when my car is not draining as much through all the winter utilities (heated seats, windshield, heater, etc.).

You mention the battery draining with heated seats, wipers, etc.

Why would you be running those with the engine off?
 

mmntech

Lifer
Sep 20, 2007
17,501
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I can't imagine they'd drain much. I take my camera inside if my car's going to be unattended for a while anyway, so it's not a target for thieves.
 

isellparts

Junior Member
Feb 11, 2014
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You mention the battery draining with heated seats, wipers, etc.

Why would you be running those with the engine off?

My theory is the battery cannot charge as much with these being actively used and as I drive short distances. Right now my camera seldom records as soon as the ignition is off which means the PMs is cutting power as it is 12.0v or lower upon ignition turning off. Am I misunderstanding.

Also, keep in mind it would be parked in a public lot for 9+ hours daily. So parking mode may get busy at times.
 
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tortillasoup

Golden Member
Jan 12, 2011
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Depends on the battery size. A fairly large 50ah battery has AT MOST 600 watt hours worth of stored electricity but that's I believe if you completely discharge it which isn't possible since most electronics have a minimum charge of like 10V needed. Also starter batteries don't like deep discharges and you can easily kill it after a few cycles of the battery.

As for keeping your battery at 12V, well you're going to get a heavily sulphated battery which means it will fail prematurely. The only thing I can suggest for you in this situation is to get a little car solar panel and find a way to put the solar panel under a window and then wire up the battery so it's always being charged. If you get a 5+ watt solar panel, you may need a charge controller.
 

hanoverphist

Diamond Member
Dec 7, 2006
9,867
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get a trip charger set up on it so it is always maintained. make sure it is one with a regulator built in so it wont over charge.

im a bit confused tho, when you start a car, the alternator will always put out almost 14v (sometimes more) while its running. if you are draining the battery with accessories, there is an issue with the charging system. while short term driving doesnt really charge the battery to a huge extent, there shouldnt be much (if any) draw down n the battery, since the alternator is supplying about 14v while the engine is running. even my wagon that sits for 167.5 hours a week will start right up and always has over 12v charge, barring that time the battery had a shorted cell. and that other time the cable got a bit corroded and had a weak connection.
 

tortillasoup

Golden Member
Jan 12, 2011
1,977
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OP has a lot of parasitic draws and probably runs down the battery while the car isn't running. Lead acid batteries are absolutely terrible for charging and with short trips but lots of parasitic draw when the car is off leads to frequent battery replacements.
 

isellparts

Junior Member
Feb 11, 2014
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So if I get a battery discharge device that cuts power at 12.4v, will I be better off than 12.0v? Again, when the car is off, if the charge is above 12.0v for the battery, it will allow the dashcam to drain it. I assume over the past few months + colder weather, it has drained to this point.

I noticed from time, when I apply brakes when stationary, my headlights dim just a bit.

Appreciate the responses thus far.
 

LTC8K6

Lifer
Mar 10, 2004
28,520
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Keep a jump starter with you in case you kill the battery?

How old is your car's battery?

If it's several years old, it may be time to get a new one anyway.
 

isellparts

Junior Member
Feb 11, 2014
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The car is brand new (late-2013). It is a Civic.

For my previous question in case it was overlooked. Is cutting off voltage at 12.4v (or a little lower, 12.2v) going to be okay for the vehicle? I would think at this capacity/charge, there is less risk of failure and the duration of the battery will be greatly extended.

All I have from my research is this link and a few other members from other forums advising me but I wanted to hear it from a real 'pro' hence why I am here.

http://dashcamtalk.com/battery-discharge-prevention/
 
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LTC8K6

Lifer
Mar 10, 2004
28,520
1,575
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The car is brand new (late-2013). It is a Civic.

For my previous question in case it was overlooked. Is cutting off voltage at 12.4v going to be okay for the vehicle? I would think at this capacity/charge, there is less risk of failure and the duration of the battery will be greatly extended.

Well, the problem is that your voltage measurement is with a load on the battery, and we don't know how much of a load it is.

In general though, yes, cutoff at 12.4V would be better than 12.0V.

As an example, 12.0V with no load would likely not start your car as it reflects a very low state of charge.
 

isellparts

Junior Member
Feb 11, 2014
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Please do not misinterpret my tone (there is no attitude) but I would rather not have anything minus the dashcam evident on the vehicle. The dashcam itself is already something I would prefer not be there but there is more pro than gain having it.
 

LTC8K6

Lifer
Mar 10, 2004
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1,575
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I would do what you plan to do, and keep a charged jumper pack in the trunk just in case.
 

isellparts

Junior Member
Feb 11, 2014
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At 12.4v cut-off, I think (again, no expert just based off research) that I would no longer have any electrical issues (not that I did, minus the very minor dimming headlights when braking) and I know you mention the jump starter as a precaution but I probably will not require this.

I only wish someone on this forum could confirm what the implications of setting the cut-off at 12.2v or 12.4v would be for such a vehicle battery in the long run as that is what it would come down to.

Appreciate your help though so far, LTC8K6! Genuinely appreciated.
 

LTC8K6

Lifer
Mar 10, 2004
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My suggestion of the jump start pack should have been a clue. :D

It is not good at all to regularly deep discharge and recharge a lead acid starting battery.

It will shorten it's life, kinda' proportional to the discharge depth.

12.4V is certainly better than 12.0V, but it is still a deeper discharge than normal.

Voltage is not really the best state of charge indicator, though.

http://batteryuniversity.com/learn/article/how_to_measure_state_of_charge
 

isellparts

Junior Member
Feb 11, 2014
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Fair enough, I only assumed at 12.4v - it would not be considered a 'deep discharge' (i.e. deep cycle). I guess I was wrong. I was hoping to squeeze a number out of it, if I am going to reduce battery life expectancy by half a year or so, what little parking mode I can get, I would take it.

As we all agreed, certainly better than having the cut-off at 12.0v right now. :)

Sigh - the headache I have gone through just for some recordings... :'(
 

LTC8K6

Lifer
Mar 10, 2004
28,520
1,575
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Well, he doesn't want the camera to shut off with the key. He wants it to stay on and keep recording, but shut off if the battery gets low.

What I might do is use a relay to switch the camera over to a small AGM battery to power it while the car is off. Then it isn't running on the car battery when the car is parked.

The small battery should run the camera for a long time, and can be removed and recharged periodically, or even set up to be recharged when the key is turned on.
 

shortylickens

No Lifer
Jul 15, 2003
80,287
17,080
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In both my 2003 chevy and 2009 nissan the plugs turn off when the car is off. No way any gadgets or toys could drain my battery.
 

LTC8K6

Lifer
Mar 10, 2004
28,520
1,575
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In both my 2003 chevy and 2009 nissan the plugs turn off when the car is off. No way any gadgets or toys could drain my battery.

The idea is to keep the dashcam running when the car is off and parked for the day, to see what happens during those times, without killing the battery to the point where the car won't start. Thus the 12.4V cutoff idea.

Obviously, the camera will need to be connected to an always on 12V source in the car, or a separate 12V source.

My Jeep has three 12v outlets. 1 switched and 1 unswitched up front, and 1 unswitched way in the back.

You can certainly kill the vehicle battery if you don't use common sense, but the unswitched outlets are very convenient.
 

isellparts

Junior Member
Feb 11, 2014
9
0
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I have concluded to not use parking mode anymore (especially in the winter when other things tax the alternator, limiting the charge it gives the battery I think -- can anyone confirm this is how it works?).

It will only draw power when the ignition is on and will turn off shortly after ignition is off.

Apparently my headlights also dim just a bit when I turn the wheel or brake, this could be the consequence of my alternator or battery being taxed? I will probably bring it into the dealer when I have time to explain the situation but will be hard to reproduce during daylight operating hours... :'(

Also to clarify - the reason it draws power when car is off is because it is hardwired to the fuse box on a fuse that works when car is off (e.g. emergency lights).