Help me construct a 30 day timer!

[Boomyal]

As far as I can find, this does not exist amoung all the name brand timers. I need a timer that will turn on every 30 days for a several hour period. The most I can find are 7 day timers and they can be horribly expensive.

I am going to build a board of battery chargers for NickleMetalHydride tool batteries. Often times these batteries sit for long periods of time without use. When you put one of the batteries in the charger, the battery will take whatever it needs then the charger will virtually shut off. (in this case, a makita charger)

After a period of time you can pull the battery out of the charger (showing fully charged), reinsert it and the charger will show that it is charging again.

Experts tell me that you should charge an idle battery every 30 days. This is what I want to do. I have 4 chargers that I want to mount to a board and plug them all into a power strip. I want a timer that will supply power for several hours then shut off.

The object is to give these idle batteries a few hours of charge every 30 days. I have numerous tools that operate off the same battery but I don't use them every day.

A charging cycle like this will keep these batteries usefull for as long as it is possible.

I just have to figure out how to accomplish this.

 

[scoutabout]

Re: Help me construct a 30 day timer!

Intriguing idea. I wonder if you could code, buy, or modify some computer-driven application to suit your needs. This site has timer software that can be wired to relays via a printer port...It seems to be based on a 24 hour model but how hard could it be to extend that to count to 720 hours (30 days...) Maybe worth a call to them to see or ask a teenager...

Get an old computer up and running in your shop dedicated to running your chargers....and surfing iboats, of course...

http://www.hottimesoftware.com/

 

[Howard Sterndrive]

Re: Help me construct a 30 day timer!

thinking it would be a fairly easy mod to the gears in one of those old Intermatic rotary motor timers.

Or just put one seven day rotary timer powering on a second one...should be able to set as far as 49 days with that.......

first timer comes on every 7th day for 1hour (e.g. Saturday at noon - 1pm)
second timer set to turn on for 1 hour every 4th hour (1 hour at midnight, 1 hour at 4 am, 1 hour at 8 am etc)
plug the charger into the second timer in the chain
therefore every 4th week, it will turn on the charger for 1 hour

 

[Tim Frank]

Re: Help me construct a 30 day timer!

Before you sink a lot of time into trying to design this, try and simulate real time scheduling of the requirement just on paper. That should show you the problem.

I faced the same type of challenge with radio batteries that supply a dozen portable VHF sets...it is a logistic exercise that you won't solve with timers and chargers...too many variables and degrees of randomness.

Simplest solution if you really have batteries that can go a month between uses is to have peel-and-stick labels that you date and apply to a battery when it is fully charged and will be idle. Keep it in a separate box which you check regularly.
The 30 days is a guideline only, and +/- 5 days or so won't matter.

 

[tx1961whaler]

Re: Help me construct a 30 day timer!

You could see if the X-10 software has a 30 day event timer on it:
http://www.activehomepro.com/activehome-pro.html
Be warned; once you start playing around with X-10 gadgets, you might have your whole house computer controlled before you know it....

 

[bigdee]

Re: Help me construct a 30 day timer!

thinking it would be a fairly easy mod to the gears in one of those old Intermatic rotary motor timers.

Or just put one seven day rotary timer powering on a second one...should be able to set as far as 49 days with that.......

first timer comes on every 7th day for 1hour (e.g. Saturday at noon - 1pm)
second timer set to turn on for 1 hour every 4th hour (1 hour at midnight, 1 hour at 4 am, 1 hour at 8 am etc)
plug the charger into the second timer in the chain
therefore every 4th week, it will turn on the charger for 1 hour

for the same price as cascading two mechanical timers I would chose this option http://www.automationdirect.com/adc...tLogic_05_(Micro_Brick_PLC)/PLC_Units/D0-05AR of course you would have to be familiar with PLC programming

 

[MTboatguy]

Re: Help me construct a 30 day timer!

Have you checked with your local Radio Shack, they used to carry all kinds of timers for various types of applications and they also used to carry circuit boards that you can make your own with IC timer chips, in fact they used to have books with plans for this type of stuff, but your probably going to be better off with on the X10 set ups that are used for turning lights on and off while you are away..

 

[boaterinsd]

Re: Help me construct a 30 day timer!

You could see if the X-10 software has a 30 day event timer on it:
http://www.activehomepro.com/activehome-pro.html
Be warned; once you start playing around with X-10 gadgets, you might have your whole house computer controlled before you know it....

aint that cool, so do you have yours set up with this?

 

[boaterinsd]

Re: Help me construct a 30 day timer!

thinking it would be a fairly easy mod to the gears in one of those old Intermatic rotary motor timers.

Or just put one seven day rotary timer powering on a second one...should be able to set as far as 49 days with that.......

first timer comes on every 7th day for 1hour (e.g. Saturday at noon - 1pm)
second timer set to turn on for 1 hour every 4th hour (1 hour at midnight, 1 hour at 4 am, 1 hour at 8 am etc)
plug the charger into the second timer in the chain
therefore every 4th week, it will turn on the charger for 1 hour

Excellent option thats very low tech. I like it .

 

[Boomyal]

Re: Help me construct a 30 day timer!

thinking it would be a fairly easy mod to the gears in one of those old Intermatic rotary motor timers.

Or just put one seven day rotary timer powering on a second one...should be able to set as far as 49 days with that.......

first timer comes on every 7th day for 1hour (e.g. Saturday at noon - 1pm)
second timer set to turn on for 1 hour every 4th hour (1 hour at midnight, 1 hour at 4 am, 1 hour at 8 am etc)
plug the charger into the second timer in the chain
therefore every 4th week, it will turn on the charger for 1 hour

Hmmmm? I'd have to do that math on that one. I couldn't easily follow your idea HS. But it sounds like it might have some merit.

A combination of smaller cheaper electronic/digital ones certainly would not work because the second one would require power to keep it's setting.

 

[Howard Sterndrive]

Re: Help me construct a 30 day timer!

that's exactly why I spec'd the motorized ones...the first one could be digital, but the second one has to be rotary motorized type

saw a couple of the old intermatic units on ebay for $20-$30...still new ones for $100+

this guy shows a qty of them for $20 each or offers
http://cgi.ebay.ca/Timer-Intermatic...3?pt=LH_DefaultDomain_210&hash=item336717fc45

 

[I Fish]

Re: Help me construct a 30 day timer!

Couldn't you use a basic 24 hour timer like this : http://www.homedepot.com/Electrical...splay?langId=-1&storeId=10051&catalogId=10053 Use it in conjunction with a 7 day digital timer? Just plug the basic timer into the digital 7 day, set the 7 day digital to be "on" 6 hours every 7th day, set the basic timer to be on 4 hours at the end of the 4th cycle? This would advance your basic timer 6 hours at the end of each week, with it being "on" 4 hours of the 4th cycle.

 

[roscoe]

Re: Help me construct a 30 day timer!

I thought about this all day at work yesterday. It gave me a headache.

This is what I came up with.







How about you just plug the power strip in once a month.

 

[Navigator_Victory]

Re: Help me construct a 30 day timer!

+1 on this idea....

Blackboard idea seems like it should work although I think the 4%/ -8.5@ is slightly off....might kick off at twenty days.....

I thought about this all day at work yesterday. It gave me a headache.

This is what I came up with.

View attachment 90790





How about you just plug the power strip in once a month.

 

[tx1961whaler]

Re: Help me construct a 30 day timer!

Just some lights with an older X10 controller. I've switched over to mostly CF lights, and they don't get along with the dimmable X10 switches

 

[Boomyal]

Re: Help me construct a 30 day timer!

I thought about this all day at work yesterday. It gave me a headache.

This is what I came up with.

View attachment 90790




How about you just plug the power strip in once a month.

Quite apropos Roscoe. That is about what my mind went through trying to compute the setting of two piggybacked timers.

I just found some nifty little GE 7 day 1800w electromechanical timers for around $9.00 ea. I haven't entirely given up that idea yet.

As far as plugging the strip in once a month, that is what I am trying to avoid. You know it would never happen on a regular basis.

 

[Pacoson71]

Re: Help me construct a 30 day timer!

Use the 7 day timer to power a 12 hr timer. The 12 hr timer needs to be mechanical dial.

Set the 7 day to power the 12 hr for 2 hrs once every seven days at midnight.

Set the 12hr timer to power the strip for two hrs at midnight.

This will turn the strip on for two hrs every 42 days.

You could increase the frequency to 3 hrs every 7 days and 3 hrs on the second to power the strip every 28 days.

Either way the two dials need to be matched for timing and length of power supplied to keep in sync.

 

[BuzzStPoint]

Re: Help me construct a 30 day timer!

If you want to tinker, What about the sprinkler control timer? The one at work I purchased was about 50 bucks. Has 4 settings and can be programed daily, weekly or monthly.

Using that plus some relays/transformers you should be able to turn on devices to allow 30 day charging.

 

[Boomyal]

Re: Help me construct a 30 day timer!

If you want to tinker, What about the sprinkler control timer? The one at work I purchased was about 50 bucks. Has 4 settings and can be programed daily, weekly or monthly.

Using that plus some relays/transformers you should be able to turn on devices to allow 30 day charging.

That might be the best idea yet. Should be simple enough to have a 24v sprinkler timer power a 24v/115v relay.

Pacoson71, I'll graph out the math on your suggestion. Not sure where one might find a 12 hour timer though.

 

[Pacoson71]

Re: Help me construct a 30 day timer!

24 hr one would work just the same. just have noon and midnight match the 7 day time on.