On Mon, 27 Mar 2017 10:23:44 -0700, Sister Ray wrote:

On Mon, 27 Mar 2017 10:39:22 -0500, "David R. Birch"
wrote:

And yet, nobody offered a way to convert a solar gate opener, or
suggested you change your door to suit one of those. Not enough
retired guys looking to share their thoughts I guess.

Or more likely semi-retired guys like me who have had or do own solar
gate openers and choose not to recommend such wimpy little devices for
the application. Mine isn't strong enough to break one new shoot of
kudzu that grew around the gate while it was open for a day.


From what I can find, many garage door openers use 12v or 24v motors
with a step down transformer. Bypassing that transformer seems the way
to go.

That certainly sounds like an uneconomical way to go unless they use
speed/acceleration control on the motor. I'll be paying attention the
next time I visit a big box store.


A small inverter can do the job, which is easier than reinventing the
wheel. You'll need a PV module, charge controller and battery either
way. Those things will be cheaper to buy separately than built into a
niche product.

Then you're right back to the constant standby losses of the idling
inverter running 24/7. One could, of course, do the switching at the
inverter but that would mean opening up the inverter and doing
something "electronic" which apparently this guy doesn't want to do.


Much talk about how to construct a system that I've seen elsewhere,
nothing from any who have actually done it.

You call it a garage door opener. I call it, for example, a
horizontal sheet mover in a cardboard box builder. Motion control is
motion control. I've designed dozens.

I described an optimized system that would open the door as fast as
possible consistent with not overstressing the door. If he wants a
low performance system built from off-the-shelf parts then he should
have asked for that.

I don't see any reason why the concept is flawed, so why isn't there a
complete system on the market already?

Practically no market for a stand-alone solar door opener. Most
people want other things like oh, let's say lights to also operate in
the garage. If on-grid, the cheapest solution is simply to bury some
NM cable from the house to the garage. Off-grid, either tap off the
existing solar/hydro system if it has the excess capacity with a stock
opener or do a custom one if the capacity is lacking.

The OP got a variety of answers to a very generalized question. If he
wanted a particular type of solution, he should have said so.

John
John DeArmond
http://www.neon-john.com
http://www.tnduction.com
Tellico Plains, Occupied TN
See website for email address