December 5, 2013

           Who recalls the picture of the house up the road with the solar water heater? You do? Good, tell me where in the blog it is and I’ll put in a link. Y’day, as I was working on the carburetor, the neighbor came along. He’d noticed the solar panels and he has a similar arrangement to top off his RV battery. We chatted twenty minutes but I had to keep working. I need that scooter.

           Meanwhile, here is a picture of the reason very few people mistake me for one of the gang. This is a typical set of objects set on the counter in front of me when I stop in on the way home. This photo is titled “Random Bar Objects” but it is pretty obvious that means my random, not the other guy’s. Otherwise the photo is insignificant as I did not leave the yard today.
           Anyway, like many SP (solar panel) enthusiasts, he is not an engineer. When I explained the power curve and how adding more panels was only a partial solution, I lost him. You see, folks, this is the advantage of belonging to a formal club. It imposes a systematic response to problem-solving that you do not get from hanging out with the gang. In a real club before long, you really have learned a thing or two. That’s why so few onlookers can contribute anything on the level that the robotics club now takes for granted. Our club evolution would drown the average Joe with information.
           She’s a hot one out there today. I put all the batteries on the trickle charger and ran tests on the panels in their present configuration. It appears I’m going to have to buy or build some voltage regulators. I could program the Arduinos, but I’m out of practice and that is one expensive option. Efficiency? Not with SPs. It appears to be certain something will work as expected you take the stated performance values of the panels and then buy nine times as many.
           I’ll check other parameters, like the wire sizes and connections. But I would require 27 panels to charge the battery—and keep it charged while running anything more than one basic light. The club is going to buy me two strips of LED lighting that will light up the pod half the power drawn by the generic Chinese bulbs. Those are neon lights that require a ballast. Anything that requires a surge of power will probably not work well with the current generation of SPs.

           How about a shot of the broken windscreen on the batbike? This also shows the seat before it got irretrievably water-damaged. As with most classic vehicles, this motorcycle requires tinkering. But it also represents a major learning experience and for me that pretty much overrides other considerations. That voltage regulator item I mentioned a few days back is internal to the motor casing. I may simply add another home-built model in-line on the battery cable.
           We got another vagrant working the neighborhood. This guy has quite the act. He bought some crutches on sale and has started bothering customers at the bakery. I was on to him instantly but he started returning when I wasn’t there. Today I called the cops. He is not only begging for sandwiches and chocolates, he was getting picky and choosing only the best chocolates and special sandwiches. What a con artist. Sorry folks, he is a fake, right down to the phony mumble-talk.
           A week ago I warned him he was headed for a free ride in the police car. Today he got it. But the guy is street clever, he might talk his way out of trespassing charges. He says he’ll quit begging if we’ll pay his bills. Utt-tutt, don’t go there with me. When I don’t have money, I go without. No running up bills and expecting others to pay them because you got problems. I’ll say again I have seen starvation and there is no such thing in America.
           Another blast from the past. My best friend at the phone company was John. She worked in traffic. She? Yep, her code name was John so we wouldn’t stir up any gossip. You know about gossip and the phone company. Well, she still works there, a lifer. The company finally wised up about printing the directory, so I can only contact her indirectly. She now has my e-mail address, so let’s wait and see what transpires. Skinny Liz. I met her in 1984.
           Last, hello Malaysia. Yes, I notice the 1,839 visits this week. I think I was there once in the 80s, but nobody today remembers me. Hold on, didn’t Guy marry a gal from Singapore? Anyway, welcome and enjoy. Be warned however, this blog does not represent the life and times of your average American. For openers, I don’t own a television.

ADDENDUM

           Here is another picture for balance. The next pod will contain self-testing features for every important circuit. I was pondering how many switches this would take when it dawned on my where I had seen a good “six-position” switch practically for free. You don’t want to know the prices of buying these switches retail. IF it looks complicated, it is.
           The pod did not deliver electricity on the scale promised by the sales literature. I will do more research but next I have a treat for anyone who wants to learn more about solar power. Due to the amount of disinformation and underinformation available out there, I will outline the basic components of a simple solar powered system. This is not conjecture, but is the actual wiring diagram schematic used on the successful pod. I could be wrong on any number of technical points, but this will get you up and running. If you skimp on any of these components, you will wind up with a toy that does you no practical good.

First, the ground rules:
           1. The solar panels vary in output depending on around a dozen factors ranging from angle to sun, construction material, temperature, and the weather. You will always need more panels and you can probably never have enough.
           2. Never connect your solar panels directly to a battery, rather always use a voltage controller. A voltage regulator is not the same thing, you must have a controller to prevent overvoltage from boiling your battery acid and protect your panels from undervoltage backflow if they drop below the battery output.
           3. You should opt for both AC and DC output. DC is more efficient at low voltages, but AC appliances are much easier to find and much cheaper. The voltage controller only outputs DC, so you will require an inverter of at least 600W. Less than 600W and you are inviting other problems. Get a real 600W, don’t pay attention to maximum or peak output propaganda.
           4. Unless you only need power in the daylight, you will require a battery to store electricity for night use. Car batteries are not good enough, you will need a deep discharge cycle marine or RV battery. They are not cheap.

You need four major components for a system. They consist of
           A. Solar panels
           B. Voltage controller
           C. A battery
           D. An inverter for AC power

The good news is that these four pieces are easy to wire together. They work on DC and thus have two wires, a positive and a negative. Make sure you know the difference and do not rely on color codes. Test always before proceeding.
The inverter is very important, you cannot get by without it. Choose a model with
           a) 12 Volt main output,
           b) 6 and 9 Volt secondary output jacks (you will eventually need them)
           c) An inverter connection (the car cigarette lighter socket type are fine)

Hook the panels to the controller, hook the controller to the battery and the inverter. Here is a generic diagram. Note the inverter can be placed in more than one location, but I prefer the ones that connect to the controller, because it indicates the controller is designed to prevent power from flowing backward from the battery to the solar panels. If that happens, say on a really dark night, you will have to replace your panels.
           One thing you will quickly notice is that anything that requires a surge of power, such as a compressor, neon ballast, or electric motors (fans) will drastically reduce the life of a solar powered system and really task your battery.

Because it is important, I will also add some advice about lead-acid batteries.
           1. Avoid ever letting them get completely discharged, even in storage.
           2. Charge them with the correct charger, preferably outdoors. Too high a voltage will boil your battery acid, which is poisonous and explosive.
           3. Don’t leave your charger unattended overnight and if it gets hot, disconnect it in a hurry. It means the internal resistance of the battery too high and these things can catch fire. It’s rare, but why take chances.
           4. Only use a trickle charger a.k.a float charger on a fully charged battery that is placed in storage. Don’t try to use a trickle charger to recharge a dead battery, or connect a trickle charger to a battery reading less than 11.5 volts. You will wreck the charger and the battery. Note that the solar panels behave very similar to a trickle charger, but the voltage controller is designed to compensate for low or dead battery cells.

So that you’ll know, lead-acid batteries are sensitive to over and under charges. In the case of a 12 Volt battery, the charging voltage should be around 13.7 volts maximum, and the battery should not be allowed to ever get below 11.5 volts. Both conditions will cause the battery to retain a charge for shorter and shorter periods until it is effectively dead.
           Also, the marine batteries which are designed to fall below 11.5 volts and still take a recharge, are not that good at the job. Try not to completely discharge any lead-acid battery, but if you do, do not leave it discharged more than a few hours. My marine battery is never allowed to drop below 8.4 volts for this reason, and because these batteries can cost a fortune.
           If you are wise, you will keep a regular 120VAC battery charger handy and top off all your storage batteries when you get the opportunity. So you should know how to read the meter on the front of the charger. It looks like it is “backwards”, but that is what you want. When your battery is fully charged, you want it to read zero amps. Why? Because at that point, the battery is pushing back on the charger just as hard as the charger is pushing forward. That is the point of balance you are seeking and leaving the charger connected any longer after that serves no purpose.

           Finally, and I’m not going to elaborate here, when you walk into a house like this one full of scientific test gear, don’t assume that bottles with liquids such as peroxide, castor bean oil, ammonia, or alcohol are uncontaminated and suitable for medicinal use. If that kind of tips you off that an idiot has been on the premises, well yeah.