[DeTomaso] Electrical questions--HELP!

[Thomas Tornblom]

Christopher Kimball skrev:
> Thank you--that makes total sense to me now.
> 
> So, since I have a one-wire alternator, does it stand to reason, to keep 
> from running large wires behind the dash to the ammeter (a crowded area) 
> I could simply run a large cable directly from the alternator 
> (piggy-backing on the "one wire" terminal) to the fan relays and stereo 
> power amp?

Yes, that will work fine.

> 
> Thanks again,
> 
> Chris

Cheers,
Thomas

> 
> 
>> From: Thomas Tornblom <Thomas.Tornblom at hax.se>
>> To: Christopher Kimball <chrisvkimball at msn.com>
>> CC: Thomas.Tornblom at hax.se, detomaso at realbig.com
>> Subject: Re: [DeTomaso] Electrical questions--HELP!
>> Date: Mon, 30 Apr 2007 05:25:24 +0200
>>
>> Christopher Kimball skrev:
>>> This is amazing and seems counter-intuitive to me--when I hooked up 
>>> the fan relays' main power, I purposely went directly to the positive 
>>> terminal of the battery (as I did with the main stereo amplifier's 
>>> power cable precisely so I would (I thought) avoid the car's 
>>> electrical system completely.
>>>
>>> I took electronics in college a LONG time ago, and my memory is fuzzy 
>>> these days, but if the fans are grounded directly to the frame (as 
>>> they are now) and the power is going to the fan motors directly from 
>>> the batery's positive terminal (which it is), how can the ammeter 
>>> even be involved in the circuit?
>>
>> Because the power to all these things comes from the *alternator*, not 
>> the battery, when the engine is running. The only way for the current 
>> to get from the alternator to the consumers is through the ammeter, 
>> which will indicate that current is flowing in the direction to the 
>> battery (== charging).
>>
>> If you instead take the power on the alternator side of the ammeter, 
>> this current is fed from the alternator to the consumer without having 
>> to go through the meter, and the meter will not indicate that it is 
>> charging, which is correct.
>>
>> It will also correctly indicate that the battery is draining if you 
>> run these things when the engine is off, as the only way for the power 
>> to get from the *battery* to the consumer is through the ammeter in 
>> the other direction, and it will indicate a discharge.
>>
>> The only current that should flow through the meter is, as SOBill 
>> said, the power going into or out of the battery.
>>
>>>
>>> I'm not questioning that you are correct, I just need to understand 
>>> what I'm missing!
>>
>> I hope the simple explanation above will help you do that :-)
>>
>> You are not alone in your thinking.
>>
>>>
>>> Thanks
>>>
>>> Chris
>>
>> Cheers,
>> Thomas
>>
>>>
>>>
>>>> From: SOBill at aol.com
>>>> To: Thomas.Tornblom at hax.se, chrisvkimball at msn.com
>>>> CC: detomaso at realbig.com
>>>> Subject: Re: [DeTomaso] Electrical questions--HELP!
>>>> Date: Sun, 29 Apr 2007 13:59:43 EDT
>>>>
>>>>
>>>>
>>>> Thomas is absolutely correct.
>>>>
>>>> The ammeter is intended to only show the current flowing into or  
>>>> out of the
>>>> battery.
>>>>
>>>> If you connect a load on the battery side of ammeter, the  current 
>>>> coming
>>>> from the alternator to supply that load will cause the ammeter to  
>>>> erroneously
>>>> indicate a charging current going into the battery.
>>>>
>>>> All loads in the car should be connected to the terminal of the  
>>>> ammeter
>>>> which comes from the alternator so that only charge or discharge  
>>>> currents from
>>>> the battery flow thru the ammeter.
>>>>
>>>>
>>>>
>>>> In a message dated 4/29/2007 2:00:02 AM Pacific Daylight Time,
>>>> Thomas.Tornblom at hax.se writes:
>>>>
>>>> Do you  have any consumers connected directly to the battery instead of
>>>> through  the cars wiring?
>>>>
>>>> The new fans perhaps?
>>>>
>>>> If so, then any current  these consumers are using will have to go
>>>> through the ammeter and it will  indicate that it is charging the
>>>> battery, when in fact the current goes to  the consumer instead of 
>>>> to the
>>>> battery.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> SOBill  Taylor
>>>> sobill at aol.com
>>>>
>>>>
>>>>
>>>> ************************************** See what's free at 
>>>> http://www.aol.com.
>>>
>>>
>>>
>>>
>>>
>>
>>
>> -- 
>> Real life:   Thomas Törnblom             Email:  Thomas.Tornblom at Hax.SE
>> Snail mail:  Banvallsvägen 14            Phone:    +46 18 444 33 21
>>              S - 754 40 Uppsala, Sweden  Cellular: +46 70 261 1372
>>                                          Fax:      +46 18 44 44 324
>>
> 
> 
> 
> !DSPAM:4635818a22795112165693!
> 


-- 
Real life:   Thomas Törnblom             Email:  Thomas.Tornblom at Hax.SE
Snail mail:  Banvallsvägen 14            Phone:    +46 18 444 33 21
              S - 754 40 Uppsala, Sweden  Cellular: +46 70 261 1372
                                          Fax:      +46 18 44 44 324