Advice on hardwiring and fuse taps

[Karlsm]

Hi all, new to the forum and I’m delighted I’ve found such an informative discussion on dash cam and/hardwiring.

Most of my questions I got answered here but before I blow up my new car and new dash cam with it, I hope you can all help me figure a few more things out before I try anything.

I have a Volvo XC40 and on the way is the new model Blackvue DR900x plus 2Ch with power magic pro.

I have identified two unused slots for constant power and switched. According to the manual, one slot is 5A and the other is 20A again both are unused.

1. In the tap I be using the top slot as bottom not needed, I’ve read (after trolling the net) that the power side of the unused fuse slot, you need to use the left leg of the tap which goes into this to keep the circuit protected? and draw power from the battery, Right or wrong? but after reading here, the orientation of the tap doesn’t matter? which has me confused.

2. As one of the unused slots is 20A for active suspension (which I don’t have), can I put any type of fuse up to 20A or do I stick with a low Amp as dashcam doesn’t draw too much amps or do I need to match this empty slot of 20A? The other empty slot is 5A so I should stick to that.

Thanks in advance,
Karl

 

[thomas-dash]

1. I don't know what type of fuse tap you are using. When I installed mine I bought an "Add a circuit" fuse type. I used the continuity test on a multimeter to see how everything was connected. What I found, looking at the fuse tap where the slots are visible and the wire on the right-hand side, was the top and bottom fuse slots were only connected on the left-side. The bottom right post was isolated. The top right post had the wire connected to it. I use the term "post" loosely in regards to the top slots since the right post is really just a piece of metal embedded in the plastic.

Assuming your fuse tap has the same set up as mine, what this means is the only way you'll get power using just the top fuse slot is for the left-side of the fuse tap to be on the hot side of the fuse slot in your car. If the bottom-right post is connected to the hot side without a fuse in the bottom slot, then there is no path for electricity to travel to reach the top slot.

This is very easy to test by just installing a fuse in the top slot and seeing which orientation powers your dash cam. If your fuse tap is like mine, then install it one way and you'll get power. Install it the opposite way and you won't get power. If your fuse tap is like mine, then there is no condition in which either the circuit from the top slot or bottom slot isn't protected because it isn't wired in parallel.

The only real difference it makes is if the bottom fuse blows. With the left post on the hot side, the side where the top and bottom are connected, the bottom fuse can blow and you'll still get power to your dash cam. With the left post not on the hot side, you'll lose power to your dash cam if the bottom fuse blows. This is because power has to flow through the bottom fuse up the post that connects the bottom and top slots and then across the top fuse and out the wire to get to you dash cam. because only one side of the "Add a circuit" connects the top and bottom fuse slots together. Again, verify this is the case for your fuse tap.

2. You want to match your fuse to what the wire in your hardwire kit is rated for. I have a Viofo A129 Duo Pro and I use a 2A fuse. I believe that's the most that specific camera will draw as well. If you have a fuse rated higher than what your hardwire kit wires are rated for, then if the wire(s) some how shorts out they'll pull more amps than what they're rated for and potentially cause the insulation on the wires to catch on fire before the fuse blows.

 

[Kremmen]

Be careful if your car is stop/start.

There are often a fair few circuits that lose power when the stop start sequence kicks in and can put a dashcam into reboot.

 

[Raising Arizona]

Hi all, new to the forum and I’m delighted I’ve found such an informative discussion on dash cam and/hardwiring.

Most of my questions I got answered here but before I blow up my new car and new dash cam with it, I hope you can all help me figure a few more things out before I try anything.

I have a Volvo XC40 and on the way is the new model Blackvue DR900x plus 2Ch with power magic pro.

I have identified two unused slots for constant power and switched. According to the manual, one slot is 5A and the other is 20A again both are unused.

1. In the tap I be using the top slot as bottom not needed, I’ve read (after trolling the net) that the power side of the unused fuse slot, you need to use the left leg of the tap which goes into this to keep the circuit protected? and draw power from the battery, Right or wrong? but after reading here, the orientation of the tap doesn’t matter? which has me confused.

2. As one of the unused slots is 20A for active suspension (which I don’t have), can I put any type of fuse up to 20A or do I stick with a low Amp as dashcam doesn’t draw too much amps or do I need to match this empty slot of 20A? The other empty slot is 5A so I should stick to that.

Thanks in advance,
Karl

If you have an unused slot for active suspension that you do not have, there may not be any power at that location. Test with voltmeter to determine if you have power.

 

[Ralph2]

If you have an unused slot for active suspension that you do not have, there may not be any power at that location. Test with voltmeter to determine if you have power.

Just a guess but willing to bet the OP has figured it out by now.