Is this voltage drop due to wire length?

[RooTxBeeR]

I had made a topic asking the other day about equal size ground and positive. I got my wires as short as could be, could take off another 2ft but that would remove any mobility I have to future set ups. I have all brand new fuses and fuse blocks, 1/0 shca ofc for power and ground runs to the back, probably about 17-18ft, Alt positive, and alt case ground and chasis ground. My voltage to what my alt reads is almost always 13.8-14.1, but what my amps sees at full tilt, it at most drops just a single volt or less difference than what the rear sees. Would that just be because of the length of wire? I resistance tested the wires after the terminals where on and read .1 ohms at most, but there was no current or anything going through to test on. Or do I still have something somewhere creating resistance? I have a 280A alt and only running a AQ750.1 so I would love for my amps to just constantly see 14v because I am not even touching what that alt can put out.

[Karkov]

IMO 17' isn't shit. The main thing about voltage drop to me is connections connections connections. This is of course assuming with vehicle on and ZERO audio playing. Everything connection good or bad had a chance to add even more resistance. In an ideal world the voltage under hood and the voltage in rear with a 20' length would be the same (vehicle on, NO audio playing). One volt is a fuck ton, unless you mean 1/10th of a volt? 0.1

In my previous set up my drop front to back was like 14.9 front and 14. 8 rear and I was pissed, lol, but I guess it's expected. If it were say 0.3 I would have chased down why but 0.1 may be as good as it gets. You should also watch voltage at amps IMO, well at least I like to...... You don't HAVE TO, but it's just nice

I know what you mean about taking that 2' out but my set up is kind of the same way, wires a little bit long for future setups, if I were you I would not remove that 2'.

EDIT: Just reread what you wrote I think I misunderstood, when at full tilt the back sees a 1 volt more voltage drop than front?? Curious what volt meters you are using to see this? Digital have slow reaction times......analog have fast reaction times. Do you use DMM and set min/max?! @full tilt I am not entirely sure what the going voltage drop front to back is, the current running through your 17' is moving so fucking fast I would think it would be less than 1 whole volt of different front to back but I truly don't know.

IMO you need someone who watches just that to chime in.....real world shit ya know, no guesses Like my noob azz is doing.....

[RooTxBeeR]

The DMM I used to measure is a digital one that doesn't have min/max set up on it. I have a cheap ass stinger for the back, used my DMM to measure what I dropped to on both and compare and at the very most I would drop a 1v difference. So let's say the front would drop to 13.7, I have only once seen 12.7 on the rear. Usually will show 13.2 or a bit higher. I can't think of what would be the cause. The connections are very tight everywhere, everything was cleaned off before putting on, made sure the wire was fully soldered into each terminal.

[RooTxBeeR]

Anyone else? What length of wire you hand and what your drop is?

[Ahmed Johnson]

Have you tried grounding the rear battery to the car instead of a full run?

[Broke_Audio_Addict]

You're way over thinking this,

Most would love to only drop one volt.

You bought your alt for the current it can produce not the voltage.

[Smoove]

[RooTxBeeR]

Have you tried grounding the rear battery to the car instead of a full run?

I have a front battery only. And yes, first it was frame grounded.

You're way over thinking this,

Most would love to only drop one volt.

You bought your alt for the current it can produce not the voltage.

I don't think you get what I am talking about. I don't even have 100a of current draw, where the alt can product 280a, and does. My battery see's 14v all day. There is a 1v difference from what the battery sees, and what my amps see. So then it is ok to have voltage drop, when I have a current draw of nearly 35% of it's full output?

[ShadeTreeMechanic]

A battery in the back would help. Take your meter and measure the voltage from one end of the wire to the other while under full load. This will be your true voltage drop. Then measure all your connections the same way. This will tell you if you have a bad connection.

[RooTxBeeR]

A battery in the back would help. Take your meter and measure the voltage from one end of the wire to the other while under full load. This will be your true voltage drop. Then measure all your connections the same way. This will tell you if you have a bad connection.

That is the plan down the line. But I don't think not having a battery in the back is the cause for my 1v difference, or is it?