Extend HK3 length

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Good afternoon,

I would like to extend the length of my Viofo HK3 hardwire kit, can I do this with a normal mini-usb extension cable, or is the wiring/voltage such that this is a bad idea?

I could just extend the wires on the otherside of the HK3, but an off the shelf USB extension would be easier.

Thanks.
 
The latter would be preferable. If you can get hold of a good quality cable, the USB solution could also work. Don't extend too much or you may run into issues.
 
Always best to extend on the 12 V side of things, a too long / too poor quality USB cable was to blame for me not capturing when i was rear ended a few years ago.
Not that the footage was needed, but since it was my first accident in 30 years it would have cool to have on tape other than from my side and front camera ( was rear ended )
 
Good afternoon,

I would like to extend the length of my Viofo HK3 hardwire kit, can I do this with a normal mini-usb extension cable, or is the wiring/voltage such that this is a bad idea?

I could just extend the wires on the otherside of the HK3, but an off the shelf USB extension would be easier.

Thanks.

The HK3 kit has I believe around 7 meters / 20 feet. What are you wiring that you need more cable length? The cable is sufficiently long to fit almost every vehicle.
 
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There are two points to consider here:
1. The resistance of the wire that you will add, this affects the voltage drop on the wire and, as a result, the final supply voltage that the dashcam will receive.
For 20AWG, the specific resistance is 0.0333 Ohm / meter, and for 28AWG it is already 0.213 Ohm / m.
If we accept: a wire 4 m long and the current consumed by dashcam is 0.4 A, then for AWG20 the voltage loss in the wire will be 0.05 V (U=R*I =ρ*l*I), and for AWG28 it will be 0.34 V.
The voltage drop on the USB line can be critical for dashcam operation (according to the USB specification, voltage is allowed in the range 5.5-4.75V). At the same time, on the 12V line, the voltage drop by the same amount is insignificant and will be "imperceptible".
Moreover, that:
2. Automotive power adapters 12V> 5V provide a stable voltage of 5V at the output when the input voltage drops to about 9V +/-
The conclusion suggests itself.
In addition, it is difficult to find good USB wires with a cross section of 20 AWG, and there is little hope that there will be pure copper, and, accordingly, voltage losses will be much higher.
 
Viofo cams are known to prefer having ample power, frequently giving trouble when using lesser HWK's and PS's even if those run other cams reliably. By extending the 12V side the cam will not see any power drop.

Phil
 
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