What Cutoff Voltage to Use?

That's a fairly large lead-acid battery, not AGM, so what I'd suggest is making sure your HKW controller is installed in an accessible place, then trying 12.2V cut-off and seeing what recording times you get. If you need more time go lower but 12.0 is as far as you should probably go. If not enough then your into powerbank territory anyway.

Also Houston gets hot so at 2 years age your battery is certain to be low on water. They call it 'sealed' but those cell caps are removable, lifting straight up with a little prying and wiggling. Top off with distilled water or a bottle of filtered drinking water same as with old batteries- to the bottom of the filler neck. When time to replace your battery it get a good AGM, your owners forum friends should be able to point you to a good one.

Phil
 
That's a fairly large lead-acid battery, not AGM, so what I'd suggest is making sure your HKW controller is installed in an accessible place, then trying 12.2V cut-off and seeing what recording times you get. If you need more time go lower but 12.0 is as far as you should probably go. If not enough then your into powerbank territory anyway.

Also Houston gets hot so at 2 years age your battery is certain to be low on water. They call it 'sealed' but those cell caps are removable, lifting straight up with a little prying and wiggling. Top off with distilled water or a bottle of filtered drinking water same as with old batteries- to the bottom of the filler neck. When time to replace your battery it get a good AGM, your owners forum friends should be able to point you to a good one.

Phil
Good point about the water, it is a "long life", not a "maintenance free" battery, check the water at least yearly, and definitely charge to 100.00% full every 3 months to clean the plates, preferably using a battery charger, then 12.0 cutoff should be OK.
 
Good point about the water, it is a "long life", not a "maintenance free" battery, check the water at least yearly, and definitely charge to 100.00% full every 3 months to clean the plates, preferably using a battery charger, then 12.0 cutoff should be OK.

Hey Nigel - stupid noobie question. How do I charge my car battery to 100%? Do I use a portable charger? I have a Black and Decker portable charger, similar to this one:

https://www.walmart.com/ip/BLACK-DE...Iky0elxtkM-kj6dqw6c5MNLpyuV3QT04aAkiwEALw_wcB

I've never had to recharge a battery, only jump dead ones, so I am unfamiliar with the process of fully recharging a battery.
 
Hey Nigel - stupid noobie question. How do I charge my car battery to 100%? Do I use a portable charger? I have a Black and Decker portable charger, similar to this one:

https://www.walmart.com/ip/BLACK-DE...Iky0elxtkM-kj6dqw6c5MNLpyuV3QT04aAkiwEALw_wcB

I've never had to recharge a battery, only jump dead ones, so I am unfamiliar with the process of fully recharging a battery.
If you go for an 8 hour drive, or 2x 4 hour drives with no parking mode use in between then that should be OK, but better to use a battery charger.

From the description on your link, I don't think it does charge car batteries, you want a car battery charger that plugs into the house power, something like:

That one is only 1.2 amps, so if the battery is half empty to when you start charging then it will need something like a 24 hour charge, if you charge it after a drive so that it is starting nearly full then an overnight charge may be enough. You want to wait until the charger switches to trickle charge before finishing.

If you can't reach the car from your house then you may need to take the car battery indoors, which may be difficult with some cars, something to consider.
 
If you go for an 8 hour drive, or 2x 4 hour drives with no parking mode use in between then that should be OK, but better to use a battery charger.

From the description on your link, I don't think it does charge car batteries, you want a car battery charger that plugs into the house power, something like:

That one is only 1.2 amps, so if the battery is half empty to when you start charging then it will need something like a 24 hour charge, if you charge it after a drive so that it is starting nearly full then an overnight charge may be enough. You want to wait until the charger switches to trickle charge before finishing.

If you can't reach the car from your house then you may need to take the car battery indoors, which may be difficult with some cars, something to consider.

I definitely can't go for 4 or 8 hour drives LOL. Looks like a trickle charger is the answer, but I live in an apartment and there are no outlets in the parking garage. I wouldn't want to leave that out for anyone to snatch up. Guess I am out of luck when it comes to fully charging my battery unless I remove the battery like you suggested and bring it into the apartment.

12volt cutoff with hardwire kit, refilling battery with distilled water, and use an external battery bank.
 
"Best practice" isn't a "necessary" practice. Even if you can only top off your battery's charge a few hours twice a year that helps, but doing nothing isn't going to greatly affect it's service life; most people do nothing and have no serious issues. And how about charging while at work? Or when visiting a friend? Or parking someplace where you've got an outlet handy once in awhile? ;) IMHO a 2A charger is a good all-round size for most people, as it can charge a dead battery enough overnight to get you started the next morning as well as charging riding lawnmower and motorcycle-sized batteries. Cheap, small, and quite handy.

Phil
 
"Best practice" isn't a "necessary" practice. Even if you can only top off your battery's charge a few hours twice a year that helps, but doing nothing isn't going to greatly affect it's service life; most people do nothing and have no serious issues. And how about charging while at work? Or when visiting a friend? Or parking someplace where you've got an outlet handy once in awhile? ;) IMHO a 2A charger is a good all-round size for most people, as it can charge a dead battery enough overnight to get you started the next morning as well as charging riding lawnmower and motorcycle-sized batteries. Cheap, small, and quite handy.

Phil

Thanks, Phil. I’ll try to do as suggested. In the meantime, I finally gotoff my lazy ass and tried to install the camera in my car and ran into a problem.

EDIT: Disregard. I forgot to turn on parking mode....

I’m pretty sure I tapped into the correct fuses (confirmed with a multimeter several times), but camera is not turning on while the car is completely off. It’ll turn on when I turn the key into the on position though. I’m thinking I either crimped the red battery wire poorly, or my cars battery just doesn’t have enough juice to stay on right now, even if I set the voltage cutoff at 12.2V

Any suggestions on what to do about it?
 
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You can check voltages with your meter. The numbers on HWK cut-offs are known to be rather inaccurate to the level of +/- 0.2V so your real number could be 12.4V which would explain this. If you suspect a poor connection then check it carefully reworking as you think necessary. There's also some chancecthat the fuses you're tapped into aren't behaving as expected. Hook your meter up on the 'parking' wire where you can see it from outsdie of the car, then close the door and see what happens. Leave it in place if it shows good for a half-hour then check again as many newer cars have a timed delay to shutdown if the car senses no activity on some circuits.. re-check the downstream side of the fuses involved for power and re-check the cam settings.

As best I can recall this cam uses the GPS to initiate parking mode. When it senses no movement over a short time, it then switches into parking mode, switching back when the car begins moving again. I'm not sure what indications of change you'll see and of course this requires the GPS to be functioning. The user manual should explain all that.

If none of this helps then it could be a bad HWK, GPS, or cam. Not likely but possible. But I think yo0u're going to find a tapped circuit isn't behaving as you thought it did, a common occurrence.

Phil
 
As best I can recall this cam uses the GPS to initiate parking mode. When it senses no movement over a short time, it then switches into parking mode, switching back when the car begins moving again. I'm not sure what indications of change you'll see and of course this requires the GPS to be functioning. The user manual should explain all that.

Phil
This is true when not using the Viofo 3-wire kit. If your using the kit, then the camera will enter parking mode based on the whether the car is on or off (based on the sensed voltage at the yellow accessory wire).
 
Thanks, Phil. I’ll try to do as suggested. In the meantime, I finally gotoff my lazy ass and tried to install the camera in my car and ran into a problem.

EDIT: Disregard. I forgot to turn on parking mode....

I’m pretty sure I tapped into the correct fuses (confirmed with a multimeter several times), but camera is not turning on while the car is completely off. It’ll turn on when I turn the key into the on position though. I’m thinking I either crimped the red battery wire poorly, or my cars battery just doesn’t have enough juice to stay on right now, even if I set the voltage cutoff at 12.2V

Any suggestions on what to do about it?


Sorry about necro'ing this old thread. I've not been looking around the other parts of this forum much, mainly just sticking to the subs concerning specific dashcams.

I use something like this to monitor the discharge curve with parking mode on. You can put a crocodile clip on and just move it from one car to the other car to gather data and establish a baseline. From there you can also see how long the parking mode has been running before cutting off (typical batteries would display a small bump in voltage once the current load goes away). On my Toyota minivan using a 56B24LS (or NS60 if you must) battery, 45 minutes of driving can run the parking mode for about 7-8 hours before cutting off.

https://www.amazon.com/gp/B01MT4583U
PS: If you shop harder you might be able to find this item for below $20.

Once a week I plug in each of my cars to this maintainer / charger thing and leave it overnight. It is an automatic charger which will decide the best voltage and current to put in at that particular stage of charging. Normally it peaks out at 13.9v and then floats at 13.1v to sustain the charge level once full. This is enough to keep the battery at ~90% charge for the next 2-3 days. If I charge till full, go for a short drive and come back, the parking mode can run for as long as 18 hours depending on how much movement there had been past my gate. I use the HK3 kit with 12.4v setting, where it typically cuts off around 12.2v and then the battery retains 12.3v for the next couple of days.

https://www.amazon.com/gp/B00CD44RQO
Once every 2 months or so, I take a tester like this and give all the cars a reading. You want to look at the State of Health (SOH) values if you're lazy to interpret the rest of the numbers. Otherwise observe the cold cranking amps (CCA) values which generally indicate the ability to start the car in the morning. The real tell-tale of battery wear is the internal resistance. From past experience, anything above 12 mOhm is about to go south. If this value hits 15+ mOhm, the battery normally fails to retain charge within the next 60 days. Bear in mind my other cars are using 42B19L and 38B20L ("NS40") which are relatively small batteries. Larger D and DIN sized batteries may behave differently.

https://www.amazon.com/gp/B07D592F7H
 
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