Sunday, August 20, 2017

I'll have to do better than this rat's nest!

Today and yesterday I worked on my wiring for the magic box. Yesterday though I didn't blog about it, I did test my magic box and wiring before I fastened the wiring to the wall. A good job too because one connection had come undone. I also had an interesting issue with a crimp connector that absolutely refused to crimp. I've never seen anything like it. In the end I resorted to using a vice but got it so tight that the wires simply snapped off.

Currently I'm charging my phone via my magic box. That's running off my 5AH Radio Shack battery which in turn is being charged via my 15W Harbor Freight solar panel. I think I've proved my system works. The voltage dropped quickly from an initial 13V before I connected the phone to 12.5V which is where it's staying. My meter connected directly to the battery is reading 12.7V so I can see my charge controller seems to be maintaining 12.5V as a norm.
 I can say I'm very happy with the initial few minutes of my test. Everything seems to be working within predicted parameters. Ignore the adjustable spanner in the photo above. That's just there to hold the rubber flaps away from the USB charging ports in order that the blue LEDs show nicely. My USB charges came with detachable rubber flaps but I left them in place.
Wiring in the control area is a bit of a rat's nest. I'll have to sort that out. At the moment everything is running off a pair of Radio Shack lead acid batteries. One is 10AH and the other is 5AH. I have a brand new Harbor Freight 35AH battery waiting for fall to be installed underneath the bus.

The plan is to remove the charge controller at the rear of the bus and to use solely one charge controller - the one in the picture directly above. One cable pair will head out from there to the battery. That cable will probably be fairly hefty. I have two 0.5A fans, a 2.5A fan and a magic box with two 3.1A sockets and a pair of meters at say 0.5A each. That all totals 10.7A. Add in the timer that I have yet to install and I'll say a good safety margin is 20A. I can therefore use a 20A cable. That's actually rather good because the controller purportedly is 20A. Solar input is 35W or about 3A maximum. I can't honestly see any need for any more than that but I will add a supplementary input for supplemental solar or wind power.

I had a go at reversing the ventilation fan simply by switching the leads. While the breeze from the intake was impressive right by the intake, I didn't find it that great to be honest. I'm not sure whether that means I need to double up on bilge blowers and change the air ducting or whether I shall just stick with what I have. Needless to say, I've come to the point with ventilation where the thing that works best seems to be to open a window and put a screen in place.

I looked around at portable air conditioning units and found several interesting candidates. I looked into mounting a window unit under the bus and it just ended up looking like an awful lot of work. Looking at the dryer section in the local hardware store I found there are detachable drier connections. Those combined with draft excluding flappers and perhaps some marine vent covers look like being a good solution. I can put air outlet plugins for AC in the bedroom and the galley. Clearly they'd need caps but that looks like one way forward. Of course, that would work only while plugged in. For travel, it seems the only solution is to simply not be inside when it's ludicrously hot.

In terms of cost, portable AC units do run more expensive. I don't think there's a great deal of difference between them though. The case sizes range tremendously with none actually matching my ideal dimensions of 10" by 15" by 26". Now those dimensions would fit quite well in through the door of a spare cupboard on the bus. That's 10" wide by 15" deep by 26" high.

I did consider making an AC unit. Initially I considered a Peltier unit but when I tried Peltier stuff it turned out not to be that great and costwise it worked out too expensive. All an AC unit really is, is a loop of tubing with a reduced tube in the middle of one side and a pump in the middle of the other side. The pump expands the gas on one side and compresses it on the other. The compressed gas radiates heat and a fan blows the heat away. The expanded gas absorbs heat and a fan blows air over the tubes, causing heat to transfer from the room to the expanded gas from which it is lost when the gas enters the compression cycle. Even ordinary air can be used as a refrigerant though the water vapor in it will freeze at low temperatures.

The problem with self build is that it takes time and experimentation when usable units just aren't outrageously expensive. Looking online they seem to go for between $200 and $400. Quite pricey but not outrageously. Recommended solutions such as mini-split and rooftop units have other issues. Cost is the main for mini-split and rooftop would raise the height of the vehicle unacceptably.

I've come to the point where everything extra that I want to add or do involves a trip underneath the bus. The only thing that does not is reconfiguring my rats nest. For that I might just get a piece of plywood, paint it the same color as the wall and lay everything out tidily then just come in and make the connections. Speaking of that, I found my Radio Shack glass filter holder has a problem. It seems to want to let go of my spade connectors. It's supposed to attach via spande connectors but they slip off rather too easily. Despite not wanting to go to blade fuses, it looks like I might just as well switch over to blade and replace the few glass fuses in my control panel with blade.

Just as I wrote that, my extraction fan cut in and I could been a really strong breeze from the window with the mesh over it. The temperature dropped a couple of degrees. It looks like the mesh in combination with my extraction fan might well be doing what's needed.

I saw online some screens with built-in fans. Those ran of 120v which made them interesting. I'd rather have some that would run off lower voltages though. I did build a window unit that runs off D batteries but it wasn't a great success in that it was very hard to mount securely in place. It worked really well though the batteries drained quickly. What I might need to do is to try to get one of the ready-built units to try. Although I've considered AC units, I really don't want to have to use AC units.

Maybe... I should just become a snowbird... Drive to Canada in summer and the Mexico in winter? That would be the best of both worlds. I'd get the good, low-priced and free social healthcare in Canada and the great food in Mexico.

Saturday, August 19, 2017

What's the difference between LED lanterns?

Two very different LED lanterns at very different price points. The lantern on the left was marked as having been made by or for GE (and bought in Walmart) while the one on the left is some no-name Chinese junk picked up from a Chinese junk retailer (in this instance Big Lots).

The similarities - both run off D cells, both had the handles snap off very soon after purchase. Both produce laughably inadequate amounts of light. As can be seen - the light produced between the two barely illuminates the little corner they're sitting in.

The differences - the GE lantern cost me $40 while the Chinese junk cost me $10. The Chinese lantern has an indeterminate lumen level. The GE claims 350 lumens. The GE had a very nice handle that could be opened and passed through a loop. The Chinese version had a pop-up hook. The GE loop simply snapped under the weight of the lantern. The Chinese loop just fell off and disappeared somewhere.

Which lantern is brighter? It looks like the Chinese lantern is brighter but this is an illusion. The LEDs are dazzling and aimed directly at the eye in such a manner as to make the lighting deeply unpleasant. In terms of usability the Chinese lantern is hopeless. It produces dazzling light that's of very low quality. I can no more read by the light of the Chinese lantern than I can dance the Polka clad in a tutu.

The GE lantern produces a better quality light that's not dazzling to look at due to the diffuser and because of the lack of bars around the glass, produces a more even light that it's actually possible though not easy to read by.

The quantity of light produced by both lanterns is by no stretch of the imagination worthwhile. They're the manufacturers having a laugh at the expense of the hapless customer. Reading what somebody else said about portable lighting, their claim was that if it wasn't a gas lantern then it didn't produce light. That's pretty close to the truth. There's a Coleman gas lantern that produces 1540 lumens. My calculation using a 100W light bulb is that 1200 lumens is the minimum needed for adequate illumination.

So, where do these lanterns stand (aside from where they should stand - inside the dumpster)? A whole bunch of lanterns must surely be as good as a single decent light? No - afraid not. Lumens do not add up like eggs. Two 20 lumen lamps does not equal 40 lumens in the way two boxes of 20 eggs equals 40 eggs. Stand two lanterns side by side and the brightness does not get greater between them. This is demonstrated adequately with this photo. No point is doubly bright! The blueness of the light has been corrected by the camera.
If lumens added then the area in the center would be twice as bright as the areas on the sides and it's not. All multiple lanterns does is to distribute poor quality lighting throughout an area. It also eggs on the scammers to produce yet more garbage for the low end of the market. Let's face it, Walmart is definitely not the upper end of the market. It's not quite as downmarket as the area taken by Big Lots and the dollar stores but it's not that far above.

So, what's the answer with lanterns and how do they compare to real lighting? At the moment there just aren't that many diffused 1200 lumen lanterns around. I've seen maybe one 1,000 lumen lantern on offer for some stupendously ludicrous price. Given that an LED lantern is dead simple to make, I'm gobsmacked by the prices.
Right there is what could be an LED lantern - a bunch of cheap LEDs and a pair of batteries. People making lanterns can get components way cheaper than people normally pay retail. I think I paid $2 for that pile of 100 LEDs a year or two back. My worthless LED lantern has just 18 LEDs. How many 18s go into 100 and how much do they cost in total? My reckoning is they have (at the price I paid), about 36 cents worth of LEDs plus pressed plastic (which is dirt cheap). If that lantern cost more than 25 cents to make, I'd be amazed. Look at it - it was sold in Big Lots for $10. Big Lots will have a huge markup on it and they paid probably only $2 for it after it had been shipped all the way from China.

What we need is for stores that import garbage from China to pay a shade more - $4 say and sell the lanterns for say $12 and have something that actually produces worthwhile light. I don't want to be sitting in the gloom of the lantern, looking at an unwrapped Mars bar wondering whether it's really a Mars bar or a freshly laid turd...

Wednesday, August 16, 2017

And on the 12th day the Lord spake and said

Let there be a kitchen so the womenfolk may cook and serve their men. And lo, a kitchen was born and women did love this kitchen and their newfound ability to serve their men.

Well, today after having my freshly painted fridge bouncing around in the back of my car for the last week or so while the paint thoroughly baked itself dry, I lifted the fridge out and installed it in my bus. I must say it looks pretty good there. I'll have to install a flat batton to stop it sliding and rig some kind of closure to keep the door shut in transit but I think you'll agree it looks pretty good.
My little kitchen is shaping up nicely with the microwave and fridge visible. The microwave probably won't last too long. It was one of the cheapie $30 microwaves from Walmart bought during their back to school sales gimmick. The fridge came with the bus. It has a 2003 date on the back and I see them on sale in Walmart for $60. Not too bad - a $90 kitchen!

The fridge protrudes a little but more by miscalculation than any other reason. Behind it is my electrical breaker box. Were it not for that, I'm sure the fridge would sit square with the countertop. Having said that, it's not a problem and all looks pretty good. Of course, when the microwave makes its way out of the box, it'll look even better!

And thus draws to a close a summer that was less devoted to bus conversion than I would have liked. As far as retitling is concerned, all the elements are there. It just needs the application to be sent off and then later the improvements start. First comes the underbus battery then comes the air conditioner and then the cold water inlet then the hot water then perhaps a flush toilet. Sometime down the line new tyres and getting the brake pedal adjusted.

Tuesday, August 15, 2017

That's a bit small!

Indeed, as the vicars wife once famously remarked to an eager young milkman, it is very small! My timer that is - get your minds out of that gutter!
According to eBay my timer had been dispatched a week ago. According to the tracking number it was two days ago that it finally hit the postbox. The important thing is it has arrived even though I probably need a magnifying glass to see it and a microscope to see the display.

It's a 16 event, 7 day timer. The way charge controllers are set up, they provide power continuously until they switch off to recharge the battery. My extraction fan can easily outpace my solar panels, a bit like the famed American motorist of the 30s who had to turn the engine of his automobile off when refueling as it used fuel faster than the pump could supply it. The purpose of the timer is to ensure the fan is operational only for as long as required rather than continuing until the battery is empty.

Thus, I've preprogrammed the timer for 15 minute operations every hour. According to my calculations, my fan should evacuate all the air in the bus every 10-12 minutes. 15 minutes should see that done and it commences operation at 10am, running hourly until 7pm. By then, summer or winter, the heat should be gone from the day. They could easily have left off their silly keyboard lock and the 7 day part of the timer.

Ominously the instructions say the timer has a 3 year lithium battery. Does that mean I'll be looking for a new timer in 3 years? Actually, I suspect all the electronics in use will die by the end of 3 years. This is largely why I don't load myself down with electronic junk. It barely lasts out of the reasonable use period.

Today was to have been a day spent working on wiring from my magic box to the battery. With my timer having arrived, I would have probably had a go at installing it. Connection is straightforward as it's just four spade connectors. Two go to the power and two are the switch. It seems polarity is unimportant.

I've been researching air conditioners, particularly the small portable variety. On my blog (which had a random advert via Adsense), I spotted an advert for a marine air conditioner. That looked interesting and I followed it. It seems though that marine air conditioners use seawater to cool the air conditioner high pressure coil. They're also ludicrously expensive!

Meanwhile, I've seen a couple of interesting portable air conditioners. It seems the exhaust vent gets really hot. Having said that, it's something that will be easy to vent through a hole in the bus floor with a duct leading out of the bus skirt with a mesh over it. The key is finding one that not only furs the space but also permits use of the exhaust hose in the same space.

Another alternative exists. I did see a portable unit that was just ten inches wide by eighteen long and about thirty six high that had the exhaust hose coming out of the top. That brings to mind all kinds of interesting ideas based on a unit that can be moved into a storage location. The downside is, according to a tradesman that used one in her grooming van, that the exhaust pipe gets very hot. It's all food for thought and various alternatives exist. I just have to keep investigating until I find an acceptable solution.

Tomorrow is another of my free days. Work starts properly on Thursday but even so, I have work related tasks that will take me to work for a couple of hours - stuff I probably won't even get paid for. That's all part and parcel of committing to an employer and doing one's best. The reality is that being exceptional is unrewarded. Being mediocre is accepted. It's all part of job satisfaction to do one's best, however. I always say, if you're not working on being brilliant then don't bother. I think Lincoln said something similar - whatever you are, be a good one.

Sunday, August 13, 2017

The strange world of the Peltier dehumidifier

Sitting in my bus today, I was dripping with sweat. It wasn't particularly hot - it was about 90F which is pretty OK. The problem was the 74% humidity. My mind turned to air conditioning and to dehumidification. The ventilation fan seems not to have cut on in forever so I'm assuming either the battery or that particular charge controller is at fault. I would have connected my latest charge controller and my latest battery but since my timer has not arrived, it's not practical.

My clothes were drenched in sweat with obvious sweat marks. Clearly not a situation that's welcome. The solution will probably be to get the ventilation working. Needless to say that's not an option right now. Remembering I have a Peltier unit that I put together out of curiosity, I decided to try it with a 12V battery. The temperature of both sides was 92F when I connected the power. I left the power connected for exactly one minute at which point the high-temperature side was over the point at which my thermometer could measure (about 200F). The lowest point I measured on the cold side was 86F. On a subsequent test, the hot side rose to over 200F again and the cold side kept climbing. When I gave up trying it was at 126F.
Previously when I used a 9V battery, I could feel a warm, cool difference. I have no idea what's going on now. It's allegedly a 12v unit so it should be doing more than that. There should have been a bigger difference. The only thing I can think of is the heat from the hot side was making the cold side warmer and that while there was a 70+ degree difference between the sides, the unit was just working as a heater rather than anything else. Quite disappointing really.

That puts me in mind of somebody else's blog entry in which they blogged about "The useless world of the Peltier effect dehumidifier". It's a very enticing technology but all the reviews I read so far are very mixed. People either rave about expensive Peltier dehumidifier or condemn them soundly. I would imagine there's a tendency for those that spend silly money on things to praise them in order to defend the fact they spent silly money. I would tend to question the bad reviews as to whether they operated the things correctly. Based on the conflicting evidence from my tests - one in which the one side was actually cold and one in which the cold side was quite hot I'm going to declare this to be yet another one of those dubious bits of electronics.

I moved on and added side brackets to my aluminum box. One didn't go quite square but what's new. That whole construction has been a fight with holes going where they wanted to go rather than where I wanted them. I'd start a hole and drill straight yet somehow the hole would end up way off where it was marked, even though when the cut started, it was spot on. Somehow the drill is drifting through the material. I'm guessing it's not a good quality of aluminum. I've had strange spots in metals before. I recall drilling some steel with a drill press when all of a sudden the drill stopped cutting. I changed drills several times and oiled the work to no avail. I ended up with a carborundum bit getting nowhere before finally cutting with a diamond tip drill. That went through like a hot knife through butter. Just because it's steel or aluminum doesn't mean it's the same all the way through - especially these days when almost all steel or aluminum is recycled and there's no telling what grades are mixed in.

It's still 66% humidity but only 91F so I'm still drenched with sweat. The humidity is more of a killer here than the heat. I'm positive that when I can finally connect my solar arrays and run everything off a single battery with a timer on my extraction fan that things will be a lot less humid and probably a lot cooler.

After the riveting, I pondered how to put my cables in and decided in the end to put them in a cable sleeve then to cut a notch in the side of the unit with my trusty angle grinder large enough to accommodate the sleeve. Then when everything is wired and the sleeve is poking out, the back can be slid into place and the whole lot screwed to the wall - wiring to be completed whenever. That's not a major task. It's fiddly but not major. Obviously 66% humidity and 91F is not conducive to doing much aside from sitting still and blogging.
The problem with blogging is while I'm blogging, I'm not doing anything toward construction. The other problem is that where I am, the wifi doesn't quite reach. I think it has to do with being in a steel bus. It's a bit of a Faraday shield. My MiFi pad is just plain uneconomical to use and the next step is a smartphone and that's more more than I want to be bothered with. It would be ideal if my flip phone offered a wifi hotspot. Sadly I don't know of any that do and I'm pretty well positive only a few of us would buy such a thing.

So why not buy a smartphone? Well, Walmart's $35 a month for a smartphone with 2GB of data would fit the bill nicely but for two things. First I don't want to have to have a monthly bill that's $20 over what I pay now. Secondly I don't want a smartphone. They're expensive to buy, have rotten battery life and take up too much pocket space. That's without mentioning that nobody calls me anyway!

So, I wired everything together with my magic box, including some nifty soldering of Radio Shack's pain in the rear non-standard pushbutton switch. Finally I put the back on the unit and touched up some of the paint.
In my construction work today I decided to do it the easy way and mount the unit on the front of the horizontal beam with a little protruding below the beam. The wires will run in my cable sleeving along the beam and into the cockpit via a small hole in the partition wall. I'll secure everything with my remaining cable clamps and drywall screws.

Earlier today I connected the bank of fuses using my piggyback connectors. It doesn't look pretty but it is functional. It's now possible to use the entire bank of 4 fuses. Tuesday being my next available day, I should be able to complete the wiring. Today there's just not enough time to do anything other than install the basic unit.

How far am I toward completing the motorhome? Well, aside from getting it retitled and getting the new magic box wired it, it's done for the moment. The 12v system needs an upgrade - it needs the new battery installed and the rear charge controller replaced by a timer that runs off the front charge controller. The two solar arrays need to be linked and I need to think about installing a cold water inlet and possibly putting in a 120v instant water heater so I can have hot water at the handbasin. As far as hot water for the shower goes, that's possible though I have not really got a foolproof method of doing it yet. Air conditioning might not be needed if i can get the ventilation working properly.

All day I've been having difficulty in trying to post photos. I've got three ready to post but whether they'll be attached by the time I publish is unknown. Blogger lets me select the images then just farts around showing me a silly little ball that keeps changing color while progressing no further despite heading off for a cup of tea while I waiting. I'm not 100% sure that it's purely a blogger problem or whether the unreliable HighesNet satellite connection could be also causing problems.

Today has been a series of problems. One of the first was that I put my freshly painted magic box back out to dry and the sky was gloriously sunny. Ten minutes later, it was pouring with rain so the paint now has poc marks. It's not as bad though as when I painted V1 of my toilet. It began to rain and washed all the paint off. Speaking about V1, I'm on V2 now and there might be a V3 after the plumbing I'm toying with comes to pass. I left space under the toilet area for a black tank. Fresh water currently goes in jerry cans but there is space behind the fuel tank for a 15 gallon water tank. There's also plenty real estate behind the rear wheels. I've shied away from that though as I figure for dry camping then jerry cans are best and for hookup, there's no need. With a flush toilet, disposal at a hookup site is easy. With a dry toilet, disposal while dry camping is easy.

While I waited for the paint to dry, I pulled out my trusty 10AA battery pack and tested my magic box. Everything worked as it should. The next stage - putting it on the wall and securing the cable using a cable clamp. That bit was surprisingly easy although I could not locate a suitable cable clamp. That's probably a trip to Harbor Freight sometime.

Illuminating the magic box should have been straightforward but for the fact the handle has fallen off yet another of my LED lanterns. It doesn't matter how much I pay for LED lanterns - they just seem to be absolute junk. On the other hand, that's pretty much my experience of all LED products. Nevertheless, I did manage to light it up and can see that my spray can of metal paint is a few shades darker than my wall paint but not obnoxiously so. My magic box is mounted on the wall, has been fully tested and is in working condition for whenever I complete the operation by installing the cables.
I can honestly say I'm glad to have completed my magic box and that it came out looking so good. I know all the minor imperfections but it's safe and it works. Wiring as I said, will have to be completed on Tuesday. That will give me a fully working battery monitoring, charger monitoring charging station for electronics. If nothing else, that makes the motorhome viable for today's technology.

Meanwhile I mentioned my battery drain issue and somebody suggested taking all the fuses out then replacing them one by one with a bulb attached between the ground of the battery and the bus ground to see which fuse lights the lamp. That sounds an excellent idea!

I can honestly say working in the heat on my motorhome is the kind of sauna that most people would pay good money for. My skin must look 20 years younger by now. Any younger and I'll be carded at the bars!

Saturday, August 12, 2017

Naked in my motorhome

It's currently 86F in the bedroom of my motorhome. Stripping off naked and just being there in my birthday suit seems like a very good idea. I don't want to shock the lampshade though! I think I've probably gone as far as I can for the moment with cooling without investing in an AC unit.

In Walmart, there was a very nice AC unit. It was a window unit that measured about 13 inches high. That would fit quite nicely under the bus. I have heard these Arctic King units just aren't very powerful. That's fine because as far as I can tell, I don't need anything particularly powerful. If I can keep the summer temperature down to say 78 that should be fine. It would need some inventive ducting and an equally inventive bay to fit it into and there's no guarantee that I'd be able to get another similarly sized unit should it fail - which the naysayers keep telling me it will. For the moment then I shall stay with ventilation and removing excess clothing.
Over the last few days I've taken delivery of an aluminum box and have mounted the two plastic panel mount holders for my Chinese USB sockets. I've also added a voltmeter. There's a 12v cigarette lighter socket included also. Now, on order I have another Chinese USB socket. I will probably replace that 12v cigarette lighter socket with a USB socket. There's also a very nice green illuminated toggle switch that lights up green when it's switched on. That should provide a color clash enough to render even the hardiest soul violently ill. The sockets have blue lights, the switch is green and the voltmeter is red.

Looking at my cigarette lighter to 120v inverter I noticed that it's both 8.8A and only produces 120v at 0.75A. That would have a struggle to power a 100W light bulb! I have not checked the power requirement of my Maha battery charger but I would imagine it would be in excess of that even used straight off 12v.

The plan was to wire all the sockets and the voltmeter together under a single fuse on my distribution panel. That plan has changed several times. Adding up the maximum power, the dual USB sockets are 3.3A each. I have two which is 6.6A. Add a 3rd and I'd have 9.9A which would work well off a 10A fuse.

The voltmeter applied to the line coming in from the charge controller should always read 12v. Not much point in measuring that. The line coming in straight from the battery is the one to measure. That should tell me when the charge controller is about to kill the power. It might even be worth putting a second voltmeter just to measure the power from the inverter and measure both. That would bring me down to four USB sockets, two of which are 1.1A and two of which are 2.2A.
I have to thank EngineeringToolbox.Com for the table above. Normally I just use "wire" for 12v applications and never have a problem. On the other hand I'm usually using very low amperages. I'll be putting a 30A cable to my big battery despite the fact my draw will be minimal. So, what will my draw be?

  • 2.5A extraction fan
  • 2 x 0.5A CPU fans.
  • 2 x 3.3A USB sockets
That's a grand total of under 11A. Assuming I add two more CPU fans and two more USB sockets (the car store has better looking USB sockets) that's an extra 7.6A or if both sockets are USB 2 then 5.4A. So I'm looking at under 20A maximum draw.

Yes, you are correct - I do have a 12V socket. That's going bye bye though for this particular project. It will be returning as an inlet for extra solar or wind power where it'll be mounted straight onto the side of the bus. 

Switching down to two dual USB sockets and two voltmeters was the work of a few seconds. It had the effect of reducing current draw to a maximum of under 7A. That still means 14ga wiring for the positive side of the two USB hosts and one voltmeter. The other voltmeter will be powered directly from the battery. That way I get to see the voltage on both sides of the charge controller. The power switch will have to be changed to a straightforward plain switch but be on the common ground side. 

With that all sorted out, I have a delay in waiting for my piggyback spade connectors to arrive and because I need to buy some 12 - 14 gauge wire. Testing the connection of the battery ground to the charge controller supply ground produced no immediate ill effects. Nothing went boom and nothing went up in smoke. That was when I tried it on one charge controller. The other was a different story.

The extraction fan was off due to low voltage. I connected the negative to the negative and the fan roared into life. That's not what I expected and isn't desirable either. Clearly I'm going to have to work this differently. As I've already drilled my holes in the aluminum box, it's hard to undrill them. Fortunately socket blanks exist for this purpose.

Hunting though my parts supply I found loads of on-off-on switches that were of no particular use for this project. I found a few lighted on-off switches that again were of no particular interest. A double pole single throw or double pole double throw would have been advantageous but none were in my supplies. I did, however, find a make contact pushbutton switch and a straightforward on-off single pole toggle switch. Now I can put the switches on the positive side where they should be.

Well, I went shopping and bought some 12 gauge wire only to find it's about the same size as some cable I already have that's not labelled. That's fine - at least I know what I have. I didn't find any replacement switches but decided in the end to go ahead with a pushbutton switch for the battery monitoring on the basis that monitoring will be fairly inaccurate on the battery anyway. Lead-acid batteries need to rest for 30 minutes before the voltage and hence charge level can be correctly assessed. 

In vain I hunted for some piggyback connectors. Those I ordered I figured would not arrive today and yet they did. Thus I was lucky not to have paid through the nose for a second set. I'm determined to complete my USB power block installation today! 

Today's massive shopping expedition included two kinds of bracket to hold my USB power block in place, two colors of 12 awg cable, a can of liquid insulation and a can of paint. My blue piggyback connectors also arrived in the post. Thus, I'm all set for this project.

While I was in Walmart I saw a $10 faucet that would fit my handbasin. I didn't buy it because that's not a project due to be undertaken until winter. Winter has two projects or perhaps three. I need to put cold water plumbing in from a hose connection. That will feed to the cold of my faucet. The other project is to put in two 120v lines. One will go to the inside of my cupboard (if I really can fit a portable AC unit in there) and the other will go to under the handbasin where there will be an instant hot water heater. I had thought about plumbing from the heater to the shower but decided the easiest way is just to put an extra faucet under the sink with a connection to the hot water so that I can fill the cooler that i use with my shower pump. There's less construction involved.

On my return from the store, I'd disconnected the batteries from my charge controllers but the lights on one were flashing away. It seems it still puts solar power through. One of my fans was spinning lazily. Clearly I've got to put a solar disconnect in as well as a battery disconnect. Just think... when the aliens invade, they won't be able to pick me up because I can turn all of my electrical devices off. The only other thing I'll need is a tinfoil hat to stop them picking up my brainwaves. I believe they're sold alongside the August 21st 2017 USA Eclipse glasses.

The first thing I did was to put the pushbutton switch in place. That had to be shaved down on one side to make it fit. Now that is a Radio Shack switch and shame on Radio Shack, it isn't a standard spade connection. In fact, after trying it with midget-sized spade connectors, I can rule those out too. Radio Shack has just forced me to solder that connection though why, I don't know as it would have taken barely a fraction of a fraction of a fraction of a cent to make the tags big enough to offer the choice of solder or midget spade. 

Next came the delay. Looking at my brackets, they were shiny metal - possibly tin plated. That meant I had to use a self-etching primer before painting them. They're what's going to hold my box in place. I'll rivet them to the sides of the box and screw the box to a cross beam. I'll have to sit what I'm charging on top of the counter or perhaps on top of the microwave. I'm assuming that if I'm solar charging things then the microwave is packed away because I'm dry camping. 

The piggyback connectors are definitely the business. They make connecting my USB ports in parallel, a real breeze. I think I always underorder connectors. I've had to reorder several times. I seem to be on the right track. Since I'd got this far, I connected the unit to a battery and it worked well. Both USB chargers lit and the voltmeter lit. There was a heck of a crackle as I connected to the electricity but that's only to be expected. The switch currently is upside down and will have to be removed and rotated. That's a matter of seconds work at this stage though.
As can be seen, it's looking pretty good. The goal is to have solar charged USB devices. While I work in the bus, I can charge my phone or my tablet or my MiFi pad (should Straight Talk MiFi ever become a viable option again). I heartily wish somebody would produce a straightforward flip phone that could be turned into a hotspot. I don't want a clunky great big smartphone. I want something with decent battery life. 

That was pretty much it for the day. By the time I'd done all that, dusk was falling. That brings me to two questions people keep asking me:
1. Why is the bus taking so long? Simply because I have a life to live around doing it and I want to get things right.
2. Why are you spending so much time on the bus. The answer to that is more complicated. I need to get it done and done as quickly as I can. My mother never lived to see its completion and always considered it to be some kind of hobby anyway. My dad's not quite sure that it's not a hobby but I want to show him it's completed, titled as a motorhome and that I've used it for a trip or two. Concurrent with that, a friend who's on his last legs is going to Canada in a few weeks and will spend 3 months there, during which time I hope to be able to drive somewhere in my motorhome to meet him.

Wednesday, August 9, 2017

New math

I decided in the end to mount the USB and 12V connectors on the galley-driving compartment partition and to have solely the CPU fan in the bedroom. This makes connections a lot simpler though when I run my cables under the bus I might well add extras in case I change my mind later (a possibility).

Looking at my two Chinese connector panels, I removed 3 of the voltmeters and replaced two with Chinese USB connectors and one 12V connector. That should fit nicely on the aluminum box that'll soon be arriving.
Now the maths works out something like this. There are two 2.1A USB sockets plus two 5v 1.2A sockets. Add to that a 2.5A fan and two 0.5A fans. That all comes to 11.1A. The cigarette lighter socket is nominally rated at 12A and the documentation on my combination dual USB and cigarette lighter socket recommends a 14A fuse. That adds up to 23.1A. Add in the one piece unit I purchased the other day and we're up to 27.1A.
If you turn your head upside down, you'll notice my charge controller tops out at 20A. That doesn't overly worry me because I'm highly unlikely to have all the devices running at the same time. Having said that, there's a big case there for putting in a resettable breaker just to make sure I don't go over 20A. Of course I could spend a ton of money on buying a massive new charge controller but until my existing 5 charge controllers, each of which can handle 20A die then there's just zero point in bothering. I cannot possibly imagine any circumstances in which I would use such a massive amount of power.

My fuse array is set up for four fuses. Those will be fan 1, fan2, fan3 and sockets. The sockets need a 6.6v fuse for the USB, an unknown quantity for the voltage meter and something for the 12v socket. I only have two devices that run off a 12V socket and to be honest I do not know their amperage. One is a battery charger for AA batteries (it also runs off 120V) and the other is a 120v inverter that produces 200W. Neither of those, I actually use.

Thus, replacing the 12V cigarette lighter socket with another USB charger socket sounds much more practical. That'll have to be ordered but I think it'll work out far better value. That would take the total power from the USB cluster to 9.9A plus say 0.1A for the voltage meter or a 10A fuse. Combined with the fans totaling 3.5A, I'm now under the maximum limit of the charge controller.
Another issue is that my 4 fuse holders have no interconnection. It seems for that I need something called a piggyback spade connector. I went to one of the multitude of car spares shops. I think it was Advance Auto and could find no piggyback connectors. In the end I hunted online and found a pack of 3 for some awful price then Walmart had a pack of 25 for some ludicrous price. Finally, eBay had a pack of 25 for under $5 including shipping. Though it'll take a few days, they should be here next week. I hate all these delays in my plans.

As far as the other USB connector is concerned, I'll have to order it and wait - that's coming from China. Eventually I might use the dual connector I purchased the other day but not in the currrent iteration.

By the time I want a 12v cigarette lighter socket, I'll probably have upgraded my battery from 35AH and will probably have added extra power input. I did email somebody the other day that makes tiny gas engines for bicycles. They're quite inexpensive and at about 45cc would do well turning a car or motorbike alternation to develop power for a 12v battery independent of solar power. Solar is fine for a wide variety of things but the power produced while it will handle my small demands, won't handle much more. I certainly doubt all the online claims I've seen of being able to run air conditioning and fridges off solar.

Meanwhile, the subject of my mysterious battery drain came up at work and one old fellow that used to work as a bus mechanic then as a driver but who now works solely as an aide piped up saying that he would suspect the alternator. I tend to agree. Reading up on alternators online, it seems this kind of thing happens when the bridge rectifier built in begins to fail. There could be other reasons too but if I can get somebody to test the alternator then I might be closer to a solution. Otherwise I'll have to wait until I can get underneath the bus again.