GSM

maybe a hydro one would be better in wales lol

Yes you could but as oxo says you will need a split charge system.

I would suggest the best way is to have the battery and solar cell working all the time and only connect it to the alarm system when the ac is off.

Technically IF the cell/cells can generate enough to recharge the nighttime losses and run the alarm then it would not need any ac at all.

The only thing I can suggest is expensive and is an auto start generator. What about the requirements for your supply authority?? there are set minimums have you looked into these?

A week? No power....in Wales is it?

Seriously, you would need a change over relay for a start. You cannot have two charging supplies on one battery.

If it is that isolated, how does the phone line stand up, or is it GSM?

Diode in series with each +ve , cathodes connected together little thought and ingenuity, much better than nothing & simpler than relays............Ok, so he loses 0.7V across each ........ just need to tweak the regulators to compensate. Not really for DIY or amateurs though.

Anyway, with a big enough battery, wouldnt need 2 charging supplies.

There is no real reason alarms cant run on a fraction of the power they currently do, apart from greed and incompetance from the manu's...

The tech is out there, pic chips run on micro amps, and are more powerfull than many older processors than ran alarms.

Things wont change though, its like cctv, corruption rules, money talks.

Come to think of it, anyone remember that old thread about PIRS, where I was told to email the manus about a risk, and I did...

Nothing happened. No reply.

The industry dont give a stuff about protecting, its about money.

Present company in general obviously are not being talked about, Im talking about manu's.

Edited May 20, 200916 yr by kensplace