The Hawkers I have are industrial quality deep cycle which are WAY more expensive than RV batteries and even these cannot withstand many cycles.
If you go to the Hawker website you will find there is an 80 page manual (PDF) on these batteries and the technology involved. They are used by companies like Telus for phone system backup. When we realise the level of engineering involved and the expense the phone industry goes to in order to provide backup then we know this is a very difficult way to do things. In general it doesn't make any sense. On Fri, Jul 22, 2011 at 09:53:15PM -0600, Darcy Brodie wrote: > > Hello, > > A standard automotive 12 volt battery will only withstand a very limited > number of discharges before becoming no good. However, RV batteries > (they are still 12 volt DC) are more designed for the cycling of the > power, and will generally withstand more discharge / charge cycles > before giving up. The down side, is that the RV batteries are > considerably more costly than a standard automotive battery. > > > Darcy > > > > On 7/22/2011 9:03 PM, [email protected] wrote: > > The wikipedia artical actually states that many switching power supplies > > can be plugged directly into a DC power source. This happens because the > > rectifiers turn the AC into DC as the first stage and after that it is all > > DC anyways. > > > > So the thing is in this mode one would need likely more than 100V DC _or_ > > the power draw would have to be less than 1/2 of what the supply is rated > > for _or_ one would have to modify it and double the capacity of the input > > side by putting two (2) rectifiers in parallel. > > > > The problem with 24V is that its so low the amperage the thing will try to > > draw will overload it (unless the draw is very low). > > > > > > > > I think in general none of these ideas are practical - I'd just go get an > > inverter and swap the 24V DC back into AC. Talk to Staples. Any cast out > > UPS does this. The APC model I have here is 24V internal (I think) and its > > rated for 450 watts. > > > > NOTE. > > > > Every UPS I have seen is terribly underpowered on the battery side. Even a > > deep cycle battery cannot handle more than a few deep discharge cycles or > > it will die! > > > > There are things like battery desulphonators which are little circuits > > designed to counter the effects of deep discharge and they are reported to > > bring back dead car batteries as well. I've looked at building some and > > would be interested to work with a small team because why should each of us > > re-invent the wheel. > > > > --------------- > > > > The problem however is that other than in very specialised applications, a > > battery power source is just not suitable. > > > > I'd like to know more about the application. > > > > > > > > > > > > > _______________________________________________ > clug-talk mailing list > [email protected] > http://clug.ca/mailman/listinfo/clug-talk_clug.ca > Mailing List Guidelines (http://clug.ca/ml_guidelines.php) > **Please remove these lines when replying _______________________________________________ clug-talk mailing list [email protected] http://clug.ca/mailman/listinfo/clug-talk_clug.ca Mailing List Guidelines (http://clug.ca/ml_guidelines.php) **Please remove these lines when replying
