Timer for battery charger

ghostlymoron

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I have a couple of 24hr plug-in timers purchased recently for £1.99 ea from Dunelm. I was wondering whether I could plug one into the other and configure them so that I can charge my battery from the mains for say 1hr/week (or thereabouts). Still pondering but the general idea is to have the first one set for 3.5 hrs per day and the 'piggyback' one for 1hr per day. Will this do what I want?
 
They are mechanical rather than electronic so it'll work assuming you have done the arithmetic correctly.

But it would be far far simpler to use a single timer that can be programmed to just one hour in a week.

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At £1.99 you might even be lucky enough for them to work for a 2nd week

:)
 
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Thinking a bit more, the only "snag", which might not matter to you at all, is that because 3½ hours is not an exact fraction of 24 hours there will be a period during which the 1 hour charging period will be split. ... I think!!

If it matters you could reset the timers manually or you could avoid it by by opting for 4 hours on the first timer and getting a charge period every 6days or 3 hours and getting a charge period every 8 days
 
Vic, I think you are right. A whole number of hours would be better and the 7 day interval is not critical. I'll have to do a spreadsheet so can see it visually.
 
If you want to catch your boat on fire, yes. I used to use mechanical timers, until I discovered they can get really hot.

I don't imagine they are that dangerous considering the number that must be in service in homes. However I would always try to site anything like that including the charger itself on a metal or ceramic plate in an area where if it burns it hopefully won't set fire to anything else. Any sort of burn out usually fuses the wiring so disconnects from the power. good luck olewill
 
I don't imagine they are that dangerous considering the number that must be in service in homes. However I would always try to site anything like that including the charger itself on a metal or ceramic plate in an area where if it burns it hopefully won't set fire to anything else. Any sort of burn out usually fuses the wiring so disconnects from the power. good luck olewill

Four mechanical timers in constant use in my home. Two are central heating system timers one is an immersion heater timer and one has the dishwasher plugged into it. The latter is of course the only one that is a plug in timer.
I expect there will also be one controlling the Xmas tree lights soon!

There is no evidence of overheating of any of them.

The OP will only be switching a small load so that should not cause any problem. Because they are plug in types mounting on a heat resisting surface does not come into the equation.
 
I have a couple of 24hr plug-in timers purchased recently for £1.99 ea from Dunelm. I was wondering whether I could plug one into the other and configure them so that I can charge my battery from the mains for say 1hr/week (or thereabouts). Still pondering but the general idea is to have the first one set for 3.5 hrs per day and the 'piggyback' one for 1hr per day. Will this do what I want?


it has worked for us over the last 20 years.

just check the contacts can stand the initial surge , & that you can physically piggy back them, as on oneof our ancient smiths ones there is not the room to plug another clock into the socket as the socket is only wide enough for a conventional plug. incidentally I use a contactor to join the banks together while the charger is on.
 
I have a requirement for a timer which will turn on only for a 3 week period within an 8 week window. Exact on/off timings for the 3 week (aprox) window not critical.

This thread has got me thinking that it might be possible with 4 (or less) basic mechanical timers. Anyone got nothing better to do than work it out?

Vic
 
Vic, I have still not verified the timings for my 2hrs per week system using 2 24hr timers! It DOES work though you'll be glad to know. However, my gut feeling with your suggestion is that you may be pushing the technology too far.
What exactly are you hoping to achieve.
 
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