Increasing power to coach/inverters/wiring/solar

[Collyn down-under]

Sent: 5/4/2003

Faderz

Hang on to the concept that the watt is the unit of energy. One amp times one volt equals one watt.

If you connect two 6-volt 100 amp hour batteries in series the result is a 12-volt 100 amp hour battery.
The wattage is thus 12 X 100 = 1200 watts.

If you connect two 6-volt 100 amp hour batteries in parallel you now have 200 amp hours at 6 volts.

The wattage is thus 6 X 200 amp hours = 1200 watts.

It really is easy much much easier to think in watts - because otherwise you have to constantly specify voltage.

Appreciate your comments re Iraq. We have only a very small army but those SAS boys of ours are extraordinary!

Collyn down-under

[Faderz]

Sent: 5/5/2003

Collyn,

Aha! It's suddenly clicked in -- thanks for the double effort . It's still a 225 amp hour battery BUT it's now at 12volts rather than 6. Makes perfect sense.

I've taken the RV out a couple of times now and the batteries haven't gone below 12.47 volts. According to Trojan, this is just below 80% - so nowhere near a deep cycle. This was definitely a really good upgrade!

[Collyn down-under]

Sent: 5/5/2003

Yes - no matter how connected (series or parallel) the batteries will give you the same amount of electrical energy - you are simply changing the voltage.

Just a brief note re measuring battery voltage.

Batteries work by storing energy as an electro-chemical reaction between the lead plates and the liquid in the battery (called electrolyte).

Particularly in cold places, this reaction has quite a time lag - in the case of deep-cycle batteries this is about a day. Thus an instantaneous meaurement tells you the meter's working but little else.

To have an accurate reading, let the batteries stand for 24 hours off-load and then check again.

Starter batteries have a larger number of thinner plates. This gives hugely more plate surface area, so the chemical reactions are much faster. An accurate reading is obtainable within a few minutes.
Incidentally our Prime Minister is reported as having a great time with George Bush - apparantly they did not even need a translator!
Collyn down-under