Hardwiring directly to battery?

max789

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Hi, all

Can a 2-channel dashcam system be hardwired directly to the car's battery, not the fuse box, with a fuse (say 5A) added for safety?

Is any there any advantage in doing so compared to hardwiring to the fuse box?

For background, and if relevant, the dashcam's parking mode will have voltage cut-off protection through a phone software setting. The parking mode is used infrequently, and for less than 5 hours if used.

Thanks in advance for any feedback.
 
You can do that no problem, but why have the problem of routing wire thru firewall and what not when you can just tap into a fuse in the fusebox that are already on a permanent connection with the battery.

So no advantages or only more work i would say
 
safer to wire to the fuse panel assuming this is a standard vehicle setup where your battery is not inside the vehicle
 
You can do that no problem, but why have the problem of routing wire thru firewall and what not when you can just tap into a fuse in the fusebox that are already on a permanent connection with the battery.

So no advantages or only more work i would say

A technician said to me that the fuse box adds electrical resistance, whilst direct hardwiring to the battery doesn't. He seems to think that this is better for running the dashcam in parking mode.

Not sure what advantage this would have. Hence this post... :unsure:
 
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A technician said to me that the fuse box adds electrical resistance, whilst direct hardwiring to the battery doesn't. He seems to think that this is better for running the dashcam in parking mode.

Not sure what advantage this would have. Hence this post... :unsure:
Sounds to me like your technician wants to charge you more by complicating a simple task.

Sent from my SM-N920P using Tapatalk
 
A technician said to me that the fuse box adds electrical resistance, whilst direct hardwiring to the battery doesn't. He seems to think that this is better for running the dashcam in parking mode. Not sure what advantage this would have. Hence this post... :unsure:

Sure there is extra resistance going through the fusebox, but I'd dare that tech to show it to me with his equipment. He;d need lab-grade equipment to measure that tiny amount, and going direct to battery would at best add a few seconds to many, many hours of available recording time.

There are really only 2 valid reasons to wire directly to the battery instead of the fusebox: 1, you need more power than can be found there and 2, it may (or may not) reduce electrical interference to sensitive electronics. Neither applies to dashcams. The drawbacks to direct wiring are adding another possible failure point to the wiring system (and anything that wire may get caught up on), loss of any car warranties, possible interference to car electronics, and unnecessary cost.

That money would be better spent getting your turn-signal lever gold plated, which would be equally effective at improving your dashcam''s performance :rolleyes:

Phil
 
Sure there is extra resistance going through the fusebox, but I'd dare that tech to show it to me with his equipment. He;d need lab-grade equipment to measure that tiny amount, and going direct to battery would at best add a few seconds to many, many hours of available recording time.
We are getting into the weeds here.. but how.. would any resistance in the wiring affect the amount of recording time? And.. electrical resistance is a function of the length of the wire and size of said wire.. Given that the supply to the fuse box is sized to provide electricity to all the cars requirements.. and that the run is as short as possible for economic reasons.. the source at the fuse box is the same as that at the battery for all practical purposes. The length of wire from the fuse box to the camera will invariably be shorter than that of a wire going directly to the battery and thus have less resistance..

There could only be one justified reason to wire directly to the battery and that would be if all the sources at the fuse box are protected by the cars logic to shut off all unspecified power demands (done on some high end cars to prevent leakage). but this was not the reason stated by the original poster.

Truly a draft discussion.................
 
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Only reason to wire direct to battery is with some euro cars due to computers that can disable circuits that show loads that shouldn't be there, that has nothing to do with resistance though
 
1, you need more power than can be found there

Thanks, Phil, for your detailed reply.

I hope you'll excuse my ignorance in these matters, as science was my weakest suit during school days. :(

"more power" - does this mean a higher or more steady voltage, or a more steady current, or both? In the context of using a dashcam in parking mode, is this relevant or provides certain advantages?

Thanks again.

Climbing a steep learning curve...
 
Climbing a steep learning curve...

The cam doesn't need to be connected directly to the battery as it doesn't draw much power (Typ. <500mA). Fuse taps will be fine as long as they are properly connected.

Either your technician is taking you for a ride or hes used to doing high current installs.

How would any resistance in the wiring affect the amount of recording time?

He meant parking mode record time, since power will be lost as heat in high resistance points like from undersized wiring or joints with poor contact.

but yes it shouldn't be an issue for Fuse box/wiring and fuse taps. They have miniscule resistance on them unless the contacts are loose or dirty.

Scotchlok/Quick Splice connectors on the other hand is sketchy, since you cant see how well the conductors are mated and the contact patch is tiny.
 
Resistance is a loss of electrical energy, so that if a BDP or cam ends recording at a given voltage, then adding resistance to it's power feed will cause the shut-off to happen sooner. In this case infinitesimally sooner and not worth worrying about.

And there can be valid reasons to not tap into the fusebox other that for bypassing computers. Like me, you may have a direct circuit handier than going to the fusebox and since it's there I use it. In time that added circuit will have at least a 25A load without my cams, and there are no places I can draw that much power from my fusebox.

Running a cam or two off a fusebox shouldn't be a problem, and running a direct tap to the battery for cams isn't really necessary or directly beneficial to the cams but it can be done if you want to do it.

Phil
 
Thanks again, all, for your valuable feedback.

The guy doing it seems to think a direct car battery hardwiring works better for the dashcam recording in parking mode for a long period.
 
Is the guy doing this a friend of yours? Like if he is doing it for free or at the same price as doing it from the fuse box. Or is he someone you don't know that's getting paid by the time and material used?
If he is the second option I really suggest you to go to another person.

Sent from my SM-N920P using Tapatalk
 
You won't notice any difference and if done wrong, direct wiring could lead to disaster. IMHO that "tech" doesn't understand things well enough to be trusted to do a safe job with this. Perfection is a good goal but is rarely necessary and is cost-effective only when it's absolutely needed ;)

We're talking about less than a 1A power draw and every circuit in every fusebox in every car can support that much extra draw. Go find somebody sensible to do the work for you; this guy is nutso :whistle: Direct wiring for a dahcam is only necessary when the car's computer design prohibits adding a draw on the fuse.

Phil
 
Thanks again, all, for your valuable feedback.

The guy doing it seems to think a direct car battery hardwiring works better for the dashcam recording in parking mode for a long period.

what vehicle do you have?

is the fuse panel inside the cabin or elsewhere in the vehicle?
 
If bull**** was tarseal your tech would be a 6 lane highway
 
There is a VERY good reason why NOT to connect to the battery if the battery is under the hood like most are, corrosion occurs around moisture and is very common on battery posts, so if you can join into a existing wire inside car this would be better, I refuse to use these the "taps" and instead cold solder, though normal hot solder is fine, then apply LIQUID TAPE over joins, this will keep out 100% of moisture permanently, ANY joint/wire/switch adds resistance but as said it's isn't going to make any difference to the amount of current used by cams, moisture can and does have a devastating effect on already bad joints so keep it dry away from under hood or trunk etc.
 
I've never had any problems tapping at the battery- most mobile Ham Radio operators have been doing this for longer than I've been alive and I ain't a young'un anymore. Probably 10,000+ successes among us alone :cool: All high-power car stereo systems are powered this way, add at lest 100.000 more successes :D

It does require corrosion protection (grease) and a solder-type terminal, not just crimped, but there is nothing inherently wrong with it and even the crimped connections will likely outlast a dashcam. Many factory battery cables are crimped on with no soldering or brazing to help, and those can last a few decades ;)

Same as with anything, the results will definitely relate directly to how well the job is done and any poorly done wiring will fail, even if it never leaves the passenger compartment :rolleyes:

Phil
 
No issues with my terminal connections and my engine bay has been submerged and washed many times. If theres early signs of corrosion i just sandpaper over the surfaces till its shiny again.

I use dielectric grease and INOX MX3 to protect exposed surfaces. For wire joints, i always dab on grease and then use adhesive heatshrink over it to seal it completely.

I prefer crimping or crimping + solder for automotive especially at high currents. You always want a mechanical hold for automotive.

Solder alone is prone to vibration and at high or overcurrent situations the heat will flow the solder joint and the wire will slip off the connector.
 
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