Dodgerdoob
New Member
Hey everyone. I'm really glad I found this site, I have electrical questions fairly regularly and now I have a resource to answer these simple questions.
My current situation is that my wife and I have bought a small farm and have got a small flock of poultry. We both have variable schedules so it makes letting out and shutting up our birds on a schedule difficult. What I need is an automatic coop door opener. I've seen commercial models that seem to work ok, but they are fairly expensive. And, I don't buy anything I think I can make. After some internet research and study, I have what I feel is a pretty good plan. Solar panel to charge controller, to SLA battery. One pair of leads to 12V digital timer, one pair of leads to a DPDT relay. The timer is wired to the control pins. Then relay to car window motor. Some where on the door track there are limit switches that stop the motor. My theory is that the timer switches "on", raises the door, trips the limit switch and the door stays up through the day. Timer shuts "off" and the door lowers until the lower limit switch trips and the door is shut and locked. So now on to the questions. What size solar panel do I need? 1 watt, 5 watt, etc. Our shortest day in Central Indiana (winter solstice) still produces 10 hours of light, if that factors in. Do I need a controller for a small panel? I do a lot of ebay shopping, will one of the generic ones from Hong Kong for $5 work? Same for the relay and and timer. I figure since all the electronics are ultimately made there anyway, why not cut out the middle man and the markup? Will leaving the timer on draw much current and deplete my battery? I would guess not since I'm only powering the relay. And on that note, what size battery do I need? The actual full 12V draw (motor actuating) is probably only 5 seconds in a 24 hour period. 5 to 7 AH SLA batteries are cheap and plentiful, would one of those work? Those are the only things I can think of right now except for one side idea: some of the charge controllers have a PV cell for controlling outdoor lights. These have preset settings so you can vary the length that a light is on. Chickens require 14 hours of light to activate their egg laying cycle. If I used one of these charge controllers, could I connect an efficient LED 12V light on the "load" terminal that would be activated by the internal PV sensor and then run my door opening system directly of the battery terminals? The battery terminals would also be connected to the "battery" terminals of the controllers. Any issues with that? This is just an afterthought, I could use an independent system for light. Thanks in advance. I'm excited for the possibilities this project could start. Thanks also to Cowboybob for your encouragement.
My current situation is that my wife and I have bought a small farm and have got a small flock of poultry. We both have variable schedules so it makes letting out and shutting up our birds on a schedule difficult. What I need is an automatic coop door opener. I've seen commercial models that seem to work ok, but they are fairly expensive. And, I don't buy anything I think I can make. After some internet research and study, I have what I feel is a pretty good plan. Solar panel to charge controller, to SLA battery. One pair of leads to 12V digital timer, one pair of leads to a DPDT relay. The timer is wired to the control pins. Then relay to car window motor. Some where on the door track there are limit switches that stop the motor. My theory is that the timer switches "on", raises the door, trips the limit switch and the door stays up through the day. Timer shuts "off" and the door lowers until the lower limit switch trips and the door is shut and locked. So now on to the questions. What size solar panel do I need? 1 watt, 5 watt, etc. Our shortest day in Central Indiana (winter solstice) still produces 10 hours of light, if that factors in. Do I need a controller for a small panel? I do a lot of ebay shopping, will one of the generic ones from Hong Kong for $5 work? Same for the relay and and timer. I figure since all the electronics are ultimately made there anyway, why not cut out the middle man and the markup? Will leaving the timer on draw much current and deplete my battery? I would guess not since I'm only powering the relay. And on that note, what size battery do I need? The actual full 12V draw (motor actuating) is probably only 5 seconds in a 24 hour period. 5 to 7 AH SLA batteries are cheap and plentiful, would one of those work? Those are the only things I can think of right now except for one side idea: some of the charge controllers have a PV cell for controlling outdoor lights. These have preset settings so you can vary the length that a light is on. Chickens require 14 hours of light to activate their egg laying cycle. If I used one of these charge controllers, could I connect an efficient LED 12V light on the "load" terminal that would be activated by the internal PV sensor and then run my door opening system directly of the battery terminals? The battery terminals would also be connected to the "battery" terminals of the controllers. Any issues with that? This is just an afterthought, I could use an independent system for light. Thanks in advance. I'm excited for the possibilities this project could start. Thanks also to Cowboybob for your encouragement.
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