Questions About Wind / Solar Controller

[Ex-Calif]

Originally Posted by goboatingnow

yes but these are available in some systems, but they are expert user stuff, setting overly high or low setpoints can have ramifications that lots of users dont understand, hence many manufacturers choose safe setpoints, that prevent tailoring. Given the tech level we are at, its strange that auto battery id systems havent arisen.

I guess the more basic question is which 12vdc in 240ac out X 3-4000 watt inverter to buy...

With all the charging options on this boat now I don't think an integrated inverter charger is in the cards. The primary purpose will be to run the 24v starter/gypsy charger and supply 240v to the boats ac outlets.

I have started internet searching and it is early days. Have also looked a couple of units in a chandlery in Thailand.

Sorry for the thread hijack...

[goboatingnow]

Originally Posted by noelex 77

The solar controllers simply drop the regulation voltage from say 14.5 to 13.8v easy



With respect I disagree. 99% of solar controllers do not use current at all to regulate. They regulate on voltage and time only.
Can you name some that use current to regulate ?

Victron Bluesolar
Xantrek XW
BlueSkies 1524 ( with IPN-proRemote)
Outback Flexmax

yes I know that the cheapo stuff uses timers, but its not the best way.

dave

[goboatingnow]

Originally Posted by noelex 77

The solar controllers simply drop the regulation voltage from say 14.5 to 13.8v easy

again a source with that typical output impedance, only can only reduce current flow, it cant influence a battery voltage unless the battery allows it. what happens is the charger reduces current until the battery naturally drops to its rest voltage , if there is another charger or source , then the voltage may not drop.

With respect I disagree. 99% of solar controllers do not use current at all to regulate. They regulate on voltage and time only.
Can you name some that use current to regulate ?

please review how power supply design works, ie look up series pass, shunt and PWM regulators. The battery state determines output voltage, I agree in bulk mode there is no regulation at all.

You are misunderstanding how solar controllers work. The timer is on voltage only. Not current. When the battery voltage is maintained at the absorption voltage for the absorption time. The solar controller will drop back to float.
Say 14.4V for 2hr would be typical. They work this way because the load current does not disturb the regulation
If the voltage drops below 14.4V the timer stops. The cumulative time at 14.4v must be 2hr.
Some solar controllers use a slightly more sophisticated timer sequence that will extend the absorb time depending on the time to reach bulk etc, but it is timer based not current based.
This is how solar controllers fundamentally work.

I have posted in another thread several controllers that use current as one of the factors to exit absorption mode. Cheapo controllers can use timers as the over all current is so low as to cause no harm anyway.

[Ex-Calif]

Another brief interlude from the debate at hand.

For us mere mortals I found this book at the Victron site. It was a great read and a very useful primer on managing batteries, charging and consumption. Real practical examples are containedd in later chapters.

Naturally there is a bit of sales pitch for Victron solutions but quite good overall.

http://www.victronenergy.com/orderbook/