Solar tracker # 2

[Basil]

I built this solar tracker. Simply as can be. It's mostly relay logic.
 
I did use a SEC E13007F2 to switch a relay off and on. How I found this was testing scrap parts that would do what I needed.
I found a ton of things that worked with 1.5 volts and up. I was amazed when this worked the way it does.
I have goolged and could not find what it is and the spec's. I know it works good with only a photo resistor to cut it on.
That's what bothers me. I fill that the spike from the relay dropping out could damage it as time goes by.
I hope someone can let me know if they see a problem.

[Basil]

The back side is nothing but a lot of little wires. The way it works is the main erray pulls in 2 master relays.
Then the photo resistor as it sees light turns on another relay to mack it track. When the sun goes down and the master relays drop out it goes back to the east. This one will be used on an old c band unit that has travel stop relays built in.
One set of wires to the solar panels,( Turns on the 2 master relays ) one set to the batteries, other to the motor. The 2 master relays are wired to run the tracker one way or the other.

[ghurd]

To tame the coil spike, use a Schottky diode in reverse parallel with the coil.
Must be a Schottky.  Regular diodes are not fast enough.

In that configuration, it is called it a flyback or freewheel diode.
G-

[Basil]

Ghurd
Thank you.
I will add it as soon as I can.

[ghurd]

"that the spike from the relay dropping out could damage it as time goes by"
Usually it happens fast, but not always.
When it does happen, it happens FAST, as in instantly.

Do it now, or it'll maybe be too late.

Some small relays have them built into the housing.
"I think" they usually have the coil marked with polarity.
(often you can see a tiny diode connected over the coil through a clear housing)

The flyback Schottky does not need to be rated as much as the coil amps.
Usually a 5817 is good for a decent sized 12V coil, and a 5819 is good for a 24V coil.

For people using "solenoids", things change fast.
Faster if they call the thing a 'charge controller'.

Also... might check your spare parts box?
Seems like I sent you something suitable, but maybe it had "metric" part numbers on it, and short bent leads?
G-

[Basil]

Thanks agian.
I'll look for it.