I have a 160 amp alternator thats supposed to be running 14.8 volts at 1000 rpm but stereo is only getting 8 volts but everything else is getting the 14.8 . At times the voltage will increase to 14.8 at stereo then for no given reason drop back to 8, which is where its at most of the time. I have a 5 farad capacitor and pretty relative with electronics but this one stumps me. help please!
where are you measuring 8V at?? that what the cap's digital readout says?? if so, did you properly charge the cap before installing it?? if you did, its prob a bad connection somewhere or a bad ground.
So I rechecked all the cables and did the big 3 and it didnt help much. The voltage will constantly change even at the same rpm. It still drops to 8 v at the capacitor but still everything up front such as headlights are getting 14.8. Anyone have an idea?
Mauricio, it sounds like a bad ground on your stereo.. Try checking this before anything else. Also, what are you using to measure it at the stereo? Most stereo's wont even be turned on at only 8 volts (most will turn off in the 9.5-10.5 volt range). Try re-running your power wire, you might have a damaged power wire as well (the one that goes to whatever is measuring at 8 volts while everything else is normal). I would even go as far as running a small 8-12 gauge wire back directly from your battery, and replacing the wire with a 12v constant to your head unit with this wire. (make sure it's fused appropriately).
Before I had the cap it was still doing the same thing which in turn I bought the cap thinking it would solve the problem. The cap has a digital volt meter and yes when it hits 8v the amps dont even turn on. What I didnt get is when I just had one amp the voltage was consistent. I have the 2 amps and cap wired to all the same ground but tomorrow I will redo the grounds an see what happens. Some told me it could be because my battery is to small which has only 500 cca could that be why?
OK PROBLEM FIXED!!! finally ! I tried different grounding locations in on the chassis and it still did the same thing. Finally just tried grounding it to the battery and boom my voltage was just siting there with barely any change at 14.2 almost at max volume... Thanks for the help guys!
grd needs to be short as possible to reduce unwanted noise! so u make it short, and tap it to the chasis..... OK But its more noise introduced to the chasis, than simply runing the grds together...
1 way is just better than the other, nothing wrong with grnd to chasis, if the chasis is grd properly, but they will always be a noticeable gain, buy directly connection to GRD!
It shouldn't matter more of a convenience issue I guess. Thisnk about it, the only thing providing polarity is the battery so the pathways would be the same distance if you ran it to the chassis or ran a separate ground led to the battery. Get it yet? Running the ground to the chassis it has to travel down the chassis, to the ground connection from your battery to your battery. Now if you ran a separate ground wire it would about the same length as the chassis anyways so noise would about the same but I would say as vehicles being unibody would accept more frequency noise than a single run of 1/0 ga. Most power supplies in todays amps are filtered through caps anyways. My opinion is to make a ground of least resistance which would be a run of wire, a chassis has too many tac welds....JMHO.. Polo
resistence is introduced with length correct, but the resistence of a car chasis is way higher than wire... current likes the path of less resistance.. ELC 101
Polo - true it's the same length, but your cars chassis (IN MOST MODELS - I should clarify this) is not going to be as conductive as a 0 gauge copper wire. Steel is not very conductive in terms of metals.
Polo - true it's the same length, but your cars chassis (IN MOST MODELS - I should clarify this) is not going to be as conductive as a 0 gauge copper wire. Steel is not very conductive in terms of metals
Not as conductive as an equal amount of copper but the chassis being as a whole will outflow a single or even a double strand of 1/0 ga easily. Even with new cars there is still a lot of metal chassis-wise so current cababilities would only be limited by the tac welds used to hold panels together.This is the reason known installers use the floor pans because they are usually stamped single sheets of steel. Now I do believe to a certain degree that noise, atmospheric and or man made radiation could be transfered to a chassis of a vehicle like an antenna so it would probably best to ground directly to battery. Even with the ground going to the battery it is not shielded so there is always noise in electrical anyways, this can and should be taken care of by the filter caps which are contained in your amplifiers power supply. Polo..
