Amp Install and Grounding Point question

skorpyo33 · May 16, 2020

ChapmanF said: ↑

Take a close look at that red battery clamp assembly. There is a high-current fuse built into it, with an accessible bolted connection for you at the other end (over the side of the battery, where the cable from the rest of the car is attached). I think it's 120 amps. It's marked, if I remember right.

Attaching at that point gives you some advantages:

You're already protected from the max current capacity of a shorted battery. If the wiring you're adding has a lower ampacity, you still need your own properly-sized fuse, but it doesn't necessarily have to be a high-interrupting-capacity fuse, because you're already downstream of one.

Most of the time (if you play music in READY mode) your power isn't coming from the battery anyway, but from the DC/DC converter at the other end of that cable. By attaching at this point, the voltage drop of the battery clamp fuse is not in your power path.

There is a similar high-capacity fuse at the forward, converter end of that same cable, so by attaching at this point, you are protected by high-capacity fuses from both possible supply directions.

This is a picture of the corresponding attachment point on a Prius Gen 1 (note the battery clamp details are a bit different). Green arrow toward lower right.

Click to expand...

Oh lord, gonna hv to do more investigative work on that. And is it true in the case of a prius your not supposed to go over 30A amp? Im installing a 20A baby 120rms powered sub 8".

skorpyo33 · May 16, 2020

ChapmanF said: ↑

Take a close look at that red battery clamp assembly. There is a high-current fuse built into it, with an accessible bolted connection for you at the other end (over the side of the battery, where the cable from the rest of the car is attached). I think it's 120 amps. It's marked, if I remember right.

Attaching at that point gives you some advantages:

You're already protected from the max current capacity of a shorted battery. If the wiring you're adding has a lower ampacity, you still need your own properly-sized fuse, but it doesn't necessarily have to be a high-interrupting-capacity fuse, because you're already downstream of one.

Most of the time (if you play music in READY mode) your power isn't coming from the battery anyway, but from the DC/DC converter at the other end of that cable. By attaching at this point, the voltage drop of the battery clamp fuse is not in your power path.

There is a similar high-capacity fuse at the forward, converter end of that same cable, so by attaching at this point, you are protected by high-capacity fuses from both possible supply directions.

This is a picture of the corresponding attachment point on a Prius Gen 1 (note the battery clamp details are a bit different). Green arrow toward lower right.

Click to expand...

Can it go to top bolt facing up?

ChapmanF · May 16, 2020

Sure, but then you just write "not" in front of each advantage listed in #20.

skorpyo33 · May 16, 2020

ChapmanF said: ↑

Sure, but then you just write "not" in front of each advantage listed in #20.
Click to expand...

So just attach to the lower bolt on side?

skorpyo33 · May 16, 2020

ChapmanF said: ↑

Sure, but then you just write "not" in front of each advantage listed in #20.
Click to expand...

Lol

Amp Install and Grounding Point question

skorpyo33 Junior Member

skorpyo33 Junior Member

Attached Files:

20200516_125325.jpg

ChapmanF Senior Member

skorpyo33 Junior Member

skorpyo33 Junior Member

Easiest Sub Install

Will this fit?

New Pioneer 7” head unit installed

Installed new headunit and unconnected wires

Upgrading Prius II ground cable

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Amp Install and Grounding Point question

skorpyo33 Junior Member

skorpyo33 Junior Member

Attached Files:

20200516_125325.jpg

ChapmanF Senior Member

skorpyo33 Junior Member

skorpyo33 Junior Member

Easiest Sub Install

Will this fit?

New Pioneer 7” head unit installed

Installed new headunit and unconnected wires

Upgrading Prius II ground cable