Consumption A329S 2CH + HK6 kit cable

[Briseide]

I received the A329S 2CH front and rear, and the HK6 hardware kit. Before installing it on the car, I performed some power consumption tests.
This is the report:

 

[Chuck McCoy]

power consumption tests

Bravissimo!

 

[Briseide]

Bravissimo!

Grazie! 😁

 

[EricSan]

Awesome data - thanks for your thoroughness! I received mine and wanted to get it in the car right away for a trip, so I didn't sit and make a thorough set of measurements in the house first.

One data point stands out to me and might be worth looking at again (for both of us): The measurement of the power draw of the HK6 regulator itself, when not connected to the camera. I measured 0.14mA at 15.4v for a total power draw of 0.002w. I'm wondering if I screwed up my measurement... I'll have to remeasure and see what I get - perhaps I had my meter set to the wrong scale (mA instead of uA) or something like that.

EDIT: my 0.14mA measurement is indeed incorrect. I have published a more thorough set of power consumption figures here.

 

[Briseide]

It was a pleasure!
I'll install the dashcam in early October. If I can, I'll try to repeat the measurements on the HK6 kit. Unfortunately, I gave the power supply and tester to my brother, so I'll have to wait.
If you could check it out, that would be great! We can verify.

 

[Finnegan]

Awesome data - thanks for your thoroughness! I received mine and wanted to get it in the car right away for a trip, so I didn't sit and make a thorough set of measurements in the house first.

One data point stands out to me and might be worth looking at again (for both of us): The measurement of the power draw of the HK6 regulator itself, when not connected to the camera. I measured 0.14mA at 15.4v for a total power draw of 0.002w. I'm wondering if I screwed up my measurement... I'll have to remeasure and see what I get - perhaps I had my meter set to the wrong scale (mA instead of uA) or something like that.

Why 15.4v? (or is that just a typo?)
I have seen my own alternator go as high as 13.8v-14.2v and I would think most electrical systems
would vary from around 12.5v to 14v. Wouldn't the input of 15.4v change the measured current flow?
To find for power, wouldn't a higher input voltage provide for a lower current draw, given a constant load?

 

[EricSan]

My cameras are not wired to the car battery. Instead, they are hard wired directly to my DIY parking battery. It is comprised of 6 individual LTO cells that each range in voltage from 2.0 to 2.65v, giving me a working range of 12.0v to 15.9v. This works perfectly with the dashcam hardwire kits that accept variable input voltage and spit out a consistent 5.2v or so. It is a 20aH battery that provides 70+ hours of singe channel recording without taxing my car's main battery for parking mode. Presently, I have 3 dashcams connected to it. The battery pack is wired to the car battery with an ACC relay, so it recharges when the car runs and I can set the recharge current to whatever I need/want without worry. LTO cells are awesome. They will last a few decades, function in sub-zero temps as well as 100 degree summer days in the sun, and the whole thing cost less than dedicated dashcam batteries with less capacity and tighter temp ranges available commercially (I already wrecked one commercial battery pack because it got too hot in the car). Plus, I can repair/update this one myself. I built two of them: one for me, one for my son.

DIY Battery Pack:

Post in thread 'LTO (Lithium Titanate Oxide) – The Ultimate Battery for Dash-Cam parking mode (DIY)'

Aug 20, 2024

So here is the final implementation of my LTO battery box. I made two of these, the one for my son was painted black and the one for my car stayed blue.

Here it is all connected together on the floor. This is just a wiring proof of concept to make sure that everything works as intended:

The battery pack is held into the case with some plumber's strap that is screwed to the bottom panel of the chassis. I also had to move the chassis feet out of the way (closer to the edge) because the screw head interfered with where the batteries would sit.

The bottom of the...

• EricSan

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• 

Battery schematic is here - the actual circuit is really pretty simple, there are only a few components:

Post in thread 'LTO (Lithium Titanate Oxide) – The Ultimate Battery for Dash-Cam parking mode (DIY)'

Jun 18, 2025

Here's the updated schematic for my LTO Parking Battery. I added a second set of outputs that will directly feed any brand's hardwire kit so I can test the parking function. The new outputs connect directly to the LTO batteries (after passing through a fuse, of course) and will provide 11-16vDC, depending on the state of charge for the battery.

Edit: Now that I'm running several cameras in my car simultaneously (for testing and comparison purposes), I'm wondering if I should have just installed a barrier strip 😉

• EricSan

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And this is how it charges from the car's main battery when the engine runs:

Post in thread 'Is the 12V socket in the trunk of my SUV reliable for battery hookup?'

Feb 10, 2025

Just be careful with how much current you pull from the utility outlet. I would not attempt to pull more than about 70-80w (no more than half of its rated capacity) from that type of port. Although fused with a 15A fuse, those utility ports are often wired with pretty thin wire that is really not meant to carry that much juice for an extended period of time. I melted a utility port plug-in adapter by charging a parking battery at 8A. I don't know if it wiggled loose or not, but the tip melted due to excess heat. The fuse was still intact. This could have caused a fire...

...

• EricSan

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[Finnegan]

@EricSan thanks, great explanation, pics, and diagram! I thought you were running a dedicated battery
setup but I was not aware that it was something you built for performance.

I really don't think dropping the supply voltage by about 10% will change the current/power by any
more then the same ~10%. More of an academic question.

I don't have a place to put an additional battery source, and my truck spends about 85% of it's time
in my driveway, so I connected my HK6 right to the fuse box and mounted a little 2a "maintainer"
under the hood. I plug in the maintainer whenever I'm home, and my 3 cams stay in Low Bit Rate
parking mode with sound, indefinitely. Plus my main battery gets a little bump.

I'm retired and my trips away from home are close-by and short. I tested twice to see how long
my system would remain active with only the main battery and I got 8-10 hours... and the truck
started just fine at 12.1v or so. Not something I want to do regularly, hence the maintainer.

 

[EricSan]

I forgot to address you second point - yes, if voltage is higher, current draw will be lower in order to maintain the same overall level of power draw: Watts = voltage x current.

I often bike to work, so my car spends a good deal of time parked in the garage. But I've also been hit a few times in the parking lot, so now I have a few extra watchful eyes on it. I also connect my main battery to a charger every few weeks because I don't drive all that often. I do this for all of the cars in the family.

With three cameras on my LTO pack, it will deplete more quickly in parking mode, so I need to keep a better eye on it. But this is an easy way to get some footage to compare when I drive it to work. I've been making some longer trips lately and the car sits in a parking deck for a few days, so the battery pack is especially useful in this situation.

 

[EricSan]

I performed some power consumption tests.

I just re-measured the power draw from the HK6 cable this afternoon. With a 14.1v battery level, I measured 144uA for a total power draw of 0.002w again. This was both with the camera attached and powered off AND with the camera not attached at all (I just unplugged the 5v output wire).

EDIT: my 0.14mA measurement is indeed incorrect. I have published a more thorough set of power consumption figures here.

 

[Briseide]

I just re-measured the power draw from the HK6 cable this afternoon. With a 14.1v battery level, I measured 144uA for a total power draw of 0.002w again. This was both with the camera attached and powered off AND with the camera not attached at all (I just unplugged the 5v output wire).

Hi, sorry, but I was only able to test today.
These are the steps I performed and the values I measured:

- Power supply turned off and connected the HK6 kit, only the Battery + (red) cable and ground point. Without the camera connected.
I turned on the power supply and measured a current draw of about 150 µA.
- As soon as I connected the ACC Wire (yellow), the current draw increased to 6 mA.
- When I disconnected the ACC wire, the current draw remained at 6 mA.
- When I decreased the supply voltage to a value lower than the value set on the HK6 kit's selector switch, after 90 seconds, the current draw went from 6 mA to 134 µA.
When I connected the camera and left it off, the current draw went from 6 mA to 8.5 mA.

I only get 150 µA when the HK6 kit cuts the power supply because the voltage is too low.

 

[EricSan]

Curious results. I'm using my parking battery to measure power draw - I put my DMM inline with the black wire of the hardwire kit. When I first disconnected things to introduce my meter, I noticed the small red LED in the HK6 body was illuminated and the body of the regulator itself felt warm to the touch, so clearly above body temp. This might represent a 6-8mA draw that you are seeing... not sure because my meter wasn't part of the wiring at this point.

Then I inserted the meter. Completing the circuit again caused my camera to turn on, so I turned it off. Yellow wire had no voltage on it because my car was off (my parking battery was not charging). I measured 144uA with the camera connected but turned off (no power to yellow wire) and I measured the same 144uA with the 4-wire output from the HK6 disconnected.

Perhaps I should insert the meter, then start the engine and turn it off again and see what happens. This is the last variable that I haven't explored... Thanks for the detailed report!

 

[EricSan]

When I connected the camera and left it off, the current draw went from 6 mA to 8.5 mA.

I only get 150 µA when the HK6 kit cuts the power supply because the voltage is too low.

You are correct! I remeasured my HK6 recently and was able to duplicate your findings: 6-8mA while connected to the camera and only dropping to the uA level once things got shut down for insufficient voltage. I have edited my posts above with a link to my newer measurements.