Resistance per connection

[Extemporaneous]

SmartGauge Electronics - How to wire alternators up - properly

Have any of you Electrical Guys read this, and do you subscribe to all that it says?
If only some of it, which point do you disagree with?

Let me know what you think.

Thanks,
Extemp.

[richardhula]

The theory is good, but in practice I would rather have a short adequately sized cable going from the alternator to the starter connection and relying on the very thick battery cable and high current connections thereafter.

The volt drop you are trying to avoid is likely to be greater with a long cable run of lesser gauge direct from alternator to wherever.

I would suggest that with the split charge system that many boats will have, feeding starter and house batteries, the splitter should be located close to the alternator. Keep cable runs as short as possible with a heavier gauge cable run to the house bank, and the starter battery feed run to the positive battery connection on the starter motor as mentioned already.

Regards

[DeepFrz]

Extemp, the article has it right (IMHO). Run the cable from the alternator to the house bank, connect the house bank to the start battery with a device like the "Echo charger". Of course you need properly sized cables from the alternator to the house bank. The article explains why to do it this way pretty well.

[Celestialsailor]

Why not just run a hefty size cable from the Alt. to the common side of the battery selector switch. Also, use a "Zap stop" diode so the Alt. does not get fried when the switch is turned off accidentally while the engine is running.

[David M]

I think its a solution looking for a non-existent problem. There are benefits to keeping things simple. The more gizmos you have, the more likely one is to break putting you out of business.

Gauge your wires properly and keep your terminals tight and clean and you wont need to worry about it.

[Extemporaneous]

Very shortly I will be purchasing my House battery bank (800 to 1000 amp hrs). To date I've been thinking of getting Trojan 27-AGM Marine/RV AGM Dual Purpose Batteries. Their 20hr rating is 100 AH. This would mean 8 or 10 batteries. Hence the concern about resistance per connection.
I could go with larger batteries, but I've read some good things about the Trojan 27-AGM.

Extemp.

[DeepFrz]

Just to be clear about one thing. I don't have any experience with the products the site was selling. I was only commenting on how to connect the alternator to the house batteries and how to charge the start battery with the Echo charge. I believe that was what the question was about.