Opus 150w

**paulpitchford** · 01-18-2005, 06:48 AM

Morning, I've been reading round the forum but am struggling to find the correct awnswer.

My opus arrived this morning and I have it on my desk and I am just trying to vision the wiring. I understand the PC side no worries. The problem I have is In the instructions for then opus, it says wire it straight to the battery on the +12v side. I understand the -12v can be wired to the chassis and the yellow wire goes to the signal on the stereo. What I need to know is should I put a inline fuse on the +12v and if so, how big?

Am I right in saying that the higher the wire rating the less current it can take? So that'll be 12 gauge for the battery and 18 gauge for the stereo signal?

I have everything ready for install now so I can't wait to get it wired up.

Thanks,

Paul.

**Scouse Monkey** · 01-18-2005, 06:59 AM

I think most people actualy wire direct to the battery with both wires and use at least 8 gauge (ie don't use 10 or above).
the fuse you need is going to be about 15A and should be as close to the battery on the +12V line.

There is a thread here with some info:

Power wires inquiry
Opus Fuses

Edit: to do a simple fuse calc: power/voltage=current so 150/12=12.5A. If you find you ar eblowing fuses when everything is running (the opus can produce over 150W i believe and there are also bad connections etc that use current) then you may want to replace it with a 20A or something in between if you can get it.

**Scouse Monkey** · 01-18-2005, 07:06 AM

Diagram that comes from Opus: http://www.opussolutions.com/images/...pplication.jpg

You also might want to add a small fuse on the ign line into the Opus 1A should be sufficient as i am pretty sure it won't be drawing more than 10W on that line!!!!!!

**paulpitchford** · 01-18-2005, 07:12 AM

Thanks very much Mr Monkey.

Reading the second thread you gave as an example got it accross ok. So if i'm right I use 8 gauge wire, and a 15A fuse as near to the battery as possible. Ground to the chassis/or battery and a 1A fuse from the back of the stereo.

??

Hope thats right,

Paul.

**Scouse Monkey** · 01-18-2005, 07:22 AM

Yup, sounds about right. I would probably try going direct to the battery -ve initially as 150W is a lot to be feeding back through an earth point. The only reason i would connect to an earth is if i was getting some ground issues with the sound.

You may want to get the system up and running with a 15A fuse and see if it will do. The lower the fuse the safer.

The 1A off your stereo sounds good. I would recommend this as you may as well be safe than sorry.

**Nic** · 01-18-2005, 07:55 AM

my 2 amps and opus are connected to the chassis, works fine for me

**Scouse Monkey** · 01-18-2005, 08:05 AM

Originally Posted by Nic

my 2 amps and opus are connected to the chassis, works fine for me

Yeah they should be ok but i have a french car with french electrics

so I am running a -ve wire so i know exactly where that current is going!

**paulpitchford** · 01-22-2005, 08:22 AM

Right, I've been shopping this morning and I am struggling to find the wire required (8 gague). The only shop that has helped me remotley is a little caravan/car supplies shop. He seemed to know his electrics but I'm not convinced what I have bought is right.

I have an inline 15amp fuse and some wire he assures me is capable of taking 250volts at 17.5amps. It is 2 core but the wire inside only looks quite thin. I was expecting great big fat red wire! He assures me this will be fine for 12v 15amp 150w.

Please please please could someone reassure me what I have bought is ok for the job.

Thanks,

Paul.

PS I'm waiting for a reply as today is fitting day and if this is right I have everything ready to fit !!!

**Scouse Monkey** · 01-22-2005, 08:39 AM

LinITX sells 8 gauge wiring kits.

Oh you need it today...then try a car stereo install place or maplins. 8 guage should be at least 3.7mm i think in diamter. have alook on google for gauge. look here and see if your wire matches up: http://ohm.bu.edu/edf_info/info/wire-resistance.html

General rule 8 gauge = 8mm squared cross section.

**paulpitchford** · 01-22-2005, 08:45 AM

Sorry I'm not sure if I understand, is the cable I have not good enough. The overall cable is quite thick but it's 2 core both wires inside are about 3-4mm each?

Paul