| Author |
Thread: Amp fuses and Alternator question |
    
Bronze Member Username: Chrisilver
Post Number: 11
Registered: Jul-08
|
| Posted on Tuesday, November 11, 2008 - 05:55 pm: |
|
If an amplifier has FIVE 30 amp fuses, does mean the alternator that its connected too can't push over the fuses combined 150 Amps, or can the alternator be any size? |
|
|
Gold Member Username: N2audio
Lawrence,
Ks
USA
Post Number: 1674
Registered: Mar-04
|
| Posted on Tuesday, November 11, 2008 - 06:22 pm: |
|
no, that's not how it works at all.
Don't look at it as current (amps) being "pushed" from one component to another.
Electrical components (the amplifier in this case) DRAW current from the charging system.
It sounds like you have an amp that's around 1500w.
An amp that size will, at times, max out most standard alternators and begin to draw current from the battery.
The question is how often will the alt be maxed out, and will there be enough down time to keep the battery charged.
If that's your only amp it might work ok on a fairly strong stock alt and batt, but if you have a 2nd amp of some size, or a smaller alt you may need to look into a high output alternator. |
Bronze Member Username: Chrisilver
Post Number: 13
Registered: Jul-08
|
| Posted on Tuesday, November 11, 2008 - 06:48 pm: |
|
Alright thanks, that's what I figured, but I was having a dumb moment. My stock civic alt is only 70 amps, so I will be upgrading most likely to a 160 amp unit. I just read the 150A fuse rating and thought i'd ask just to be sure. The amplifier is sundowns sae 1200 |
Gold Member Username: N2audio
Lawrence,
Ks
USA
Post Number: 1676
Registered: Mar-04
|
| Posted on Tuesday, November 11, 2008 - 11:14 pm: |
|
A 160A should get it done w/o much trouble, and leave enough slack to add a good amp for some full range speakers. |
Bronze Member Username: Chrisilver
Post Number: 15
Registered: Jul-08
|
| Posted on Tuesday, November 11, 2008 - 11:42 pm: |
|
*A 160A should get it done w/o much trouble, and leave enough slack to add a good amp for some full range speakers.*
That is my plan, sub first then, save up for a nice component set. Would a 160 amp alternator be plenty to power a 1200 w amp as well as maybe a 400 w for speakers, along with the regular car functions a/c ect.? |
Gold Member Username: N2audio
Lawrence,
Ks
USA
Post Number: 1678
Registered: Mar-04
|
| Posted on Wednesday, November 12, 2008 - 12:31 am: |
|
160A should give you TONS of headroom in a civic. 1600w should be no problem at all. |
Bronze Member Username: Chrisilver
Post Number: 18
Registered: Jul-08
|
| Posted on Monday, November 17, 2008 - 12:56 am: |
|
Could you suggest me some companies the make good quality alternators? I was planning on one from alterstart, but I read some pretty bad stuff about them hardly even working at normal idle speed. There's endless reviews on subs, amps and other parts, but alternators seem to be a bit of a gray area in car audio, I can't much good information on them. Any input would be appreciated |
Gold Member Username: Nd4spd18
Philadelphia,
PA
Post Number: 8968
Registered: Jul-06
|
| Posted on Monday, November 17, 2008 - 02:09 am: |
|
DB Electrical
Motor City Reman
Two best HO alt companies I have dealt with. |
Gold Member Username: Snowball123
West Allis,
WI
Post Number: 1682
Registered: Oct-07
|
| Posted on Monday, November 17, 2008 - 09:57 am: |
|
mechman |
|
|
Bronze Member Username: Chrisilver
Post Number: 19
Registered: Jul-08
|
| Posted on Wednesday, November 19, 2008 - 12:05 am: |
|
I have another quick question,
What determines the size of fuse you need in between the battery and the amp? |
Gold Member Username: Nd4spd18
Philadelphia,
PA
Post Number: 8979
Registered: Jul-06
|
| Posted on Wednesday, November 19, 2008 - 11:00 am: |
|
Fuse size is based on wire gauge
Wire Gauge, Current Flow, Max Total Amp Power
Class AB (60% eff), Max Total Amp Power
Class D (75% eff)
0 awg 330 amps 2731 watts 3414 watts
1 awg 262 amps 2168 watts 2710 watts
2 awg 208 amps 1720 watts 2151 watts
3 awg 165 amps 1365 watts 1707 watts
4 awg 131 amps 1084 watts 1355 watts
5 awg 104 amps 860 watts 1075 watts
6 awg 82 amps 683 watts 853 watts
7 awg 65 amps 542 watts 677 watts
8 awg 52 amps 430 watts 537 watts
9 awg 41 amps 341 watts 427 watts
10 awg 33 amps 271 watts 339 watts
11 awg 26 amps 215 watts 269 watts
12 awg 21 amps 171 watts 213 watts
13 awg 16 amps 135 watts 169 watts
14 awg 13 amps 107 watts 134 watts |
Bronze Member Username: Chrisilver
Post Number: 21
Registered: Jul-08
|
| Posted on Wednesday, November 19, 2008 - 06:49 pm: |
|
So if I have 1/0 gauge wire and a 250A alternator do I need like a 300-330 amp fuse? or around 250 amps? The wire is 17.5' long |
Gold Member Username: Nd4spd18
Philadelphia,
PA
Post Number: 8988
Registered: Jul-06
|
| Posted on Thursday, November 20, 2008 - 05:01 am: |
|
yeah 0 gauge wire you need a 300 or 325 amp fuse |
Gold Member Username: N2audio
Lawrence,
Ks
USA
Post Number: 1690
Registered: Mar-04
|
| Posted on Friday, November 21, 2008 - 12:52 pm: |
|
If the sum of the maximum current draw of your amps don't add up to the maximum current limit of the wire I suggest fusing to only what the amps need for a little extra safety factor.
Sounds like you're looking at a total current draw of about 200A so there would be no point in fusing the wire at 300A except to give the wire more time to heat up if you ever do get a short. |
