I'm searching through the forum for help on a major problem I'm experiencing... I'm so confused with all the mysterious things I'm seeing. I really hope you can shed light on my problem - would appreciate it so very much.
A summary of my situation:
I'm running a 24V solar system using this regulator http://www.stecasolar.com/index.php?Steca_Solsum_F_en
- 10A version. My batteries NEVER goes below 12.0V during night time or cloudy periods. I check their voltages monthly, always reading 13.5+V. Thus, batteries I believe are very healthy. Average age of each battery is 10 months.
In the beginning, I had stability problems at this specific site (running RB600's). Its a 15m tower, with the solar panels, batteries and regulator at the bottom of the tower. The output of the regulator went up the tower to the RB's. The symptoms was that the router will just die. I'll drive out to the tower, find that the board was dead (no lights burning, nothing), pull out and push in DC jack, all fine again. Then after a few days, same problem.
I've tried 10 000uf 35V caps between the RB's and regulator output - no luck. Then, eventually I moved the regulator up the tower to the router boards and changed the gauge of the wire to a nice thick rip cord. Thus, the solar panel and battery wires now ran up the tower to the regulator. Note: I draw my power for the RB's from the output of the regulator, not directly from the batteries.
Anyway, suddenly my tower became stable, for 120+ days... this took me through the dry cold season. Then the humid, wet, and thunder stormy season started... this was about 2 months ago. All suddenly became unstable again, but with different symptoms.
The board will do random reboots and it will sometimes hang. When inspecting the board, its seem to be running, lights are burning etc, but the board is hanged (I'm running ROS 4.13). Have to pull and push the DC jack to reboot, all is fine for a while again. Note: All the equipment is in weather proof boxes. They are perfectly dry inside. All my RB's and antennas are properly grounded to the tower. Eventually I've also fitted a GSM module to remote reset the routers.
First I thought the solar regulator became faulty. Changed the regulator, no difference. Somebody mentioned that the diodes on the solar panels might be damaged. I've tested my solar panels individually, each giving an open circuit voltage of +-21.5V. Believe the solar panels are fine.
Then I replaced the router boards (did not replace wireless cards). No difference. I've also changed the system to 12V - no difference.
What is causing the instability? I've spend hundreds of hours trying to solve this problem and lots of money with no luck.
Today, the following started to happen: The board will reboot every 15min (with log entry, 'Probable Power Outage') - a clear symptom of a power supply issue?! I drove up to the tower, disconnected the solar panels, took the battery voltage (bank of 4 x 102AH deep cycle batteries) - all read 13.0V (cloudy day). Thus, batteries are fine... I then decided to take the regulator out of the equation. I'm now running this tower straight from the batteries, not solar panels connected. I want to see if the board can last for more than 2 days. If so, then I believe the solar regulator is the problem (but, remember this site was stable for 120+ days on this same make/type of regulator?!).
A friend of mine also recommended putting another regulator between the output of the solar regulator and the RB's. He recommended building it myself using a LM7818 with 10000uf 35V caps on the input and output.
Tanker, can you give advice? I see you are recommending the SD-150B-24 from Mean Well. I can get this device here in South Africa. Do you think this is my problem, that the output of the solar regulator is not nice and clean?
Would really appreciate any advice.