# Digital timer for off-gridders and more



## bunkerbob (Sep 29, 2009)

Just a note concerning timers for anyone off the grid. I have been using a Intermatic SS 8 inwall digital timer to run my 220vac well pump, it switches the hot side of the 220 only, up to 15 amps, and times the pump to come on between 11:30am and 1pm every day during peak solar hours. It keeps the 2 - 5000 gallon water tanks full. It has been acting up as of late and I went to purchase another, discontinued by manufacturer!. Good news it has been replaced with the Intermatic STO1C with a lithium battery instead of the AAA alkaline. These do not require any external voltage to run, just the internal replaceable battery.
Intermatic Heavy Duty Digital Self-Adjusting Wall Switch Timer - White It looks like they are out of stock, but I bought one on EBAY.:2thumb:


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## NaeKid (Oct 17, 2008)

With the first one flaking out on you - do you think it would be a good idea to stash a couple of them for "just-in-case" scenerios ... it would really suck if the one you just got died on you and it took a couple weeks to get replacements .. 

Also - just wondering - is the battery in the unit rechargable and / or replaceable?


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## bunkerbob (Sep 29, 2009)

NaeKid said:


> With the first one flaking out on you - do you think it would be a good idea to stash a couple of them for "just-in-case" scenerios ... it would really suck if the one you just got died on you and it took a couple weeks to get replacements ..
> 
> Also - just wondering - is the battery in the unit rechargable and / or replaceable?


It took 3 years to start going bad, it still works on auto, but sometimes doesn't work on manual. Your right, that's why I just got another. I'm going to take the old one apart and look at the relay circuit to see if its repairable. The batteries are replaceable, no current to recharge internally. New one looks like a 6v lithium type, replacements will last a long time, old is typical AAA style.
This is to run the system automatically, I can still turn on the well pump without the timer.
I'm also working out a way through the inverters to limit the pump coming on when the system is low. The Xantrex inverters have 2 internal relays, one N.O. and the other N.C., that are controlled by hysteresis voltage control points, another words I can have them open up at a low volt setting and close when that voltage comes up. This way it won't drain the system batteries at a non-opportune time.


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