Friday, March 31, 2017

2016 MacBook Pro

I'm in the process of transferring data from a MacBook (MB) (early 2015) to a late 2016 MacBook Pro (MBP). The two machines are directly connected using gigabit Ethernet adaptors plugged into USB-C ports. And I'm getting about 400 Mb/s. I guess that's about ⅔ of the read speed of the MB SSD. I initially tried to do the transfer using WiFi and after about 3% completion, the status said 2 minutes until completion. And it sat there for two hours before I cancelled it and dug out the Ethernet dongles.

Quite a performance difference between the two laptops. The MB is a 1.3 GHz Core M with 8GB of memory. The MBP is a 3.3 GHz Core I7 with 16GB of memory. Both have SSD drives though the MBP has double the capacity and at least 3x the read and 10x the write speed. The read speed pegged the scale on the Blackmagic speed test at 2 GB/sec and the write speed was 1.8 GB/sec. The MB is a very light 2.03 lbs with the MBP weighing in at 3.02 lbs. It feels much heavier. The picture shows a comparison of the 15" 2012 MBP, the 13" 2016 MBP and the 12" MB. I have been using the 15" Apple laptops since the 2001 PowerBook G4 Ti. For travel, I've used the 11" MB Air and the 12" MB but both seemed pretty underpowered compared to the MBP but the SSDs kind of compensated for the lackluster performance making them both great travel laptops.

There has been a lot of discussion about the touchbar on the new MBP. When I saw the demo videos I wasn't really sure what value it adds. But I don't hate it either. The fingerprint reader to log in is incredibly fast and easy to use. It is also is a physical power button. So far, no complaints. Another complaint seen on the Internet was the keyboard. It is a similar design to the MB but feels much better and is much more positive. And a bit noisier. It has a huge trackpad with the same device to simulate a physical "cick" even though it doesn't move at all. It feels convincing enough to me. Plus, I set the preferences to just tap and not press anyway.

For the MB, I had already accumulated some dongles as it only had a single USB-C port. Fortunately, the new MBP has four of the type C ports.

BTW, it snowed several more inches today but warmed up to around freezing by mid-afternoon. I didn't ride today but have been for most of the week. Just too lazy to take any pictures...

Saturday, March 25, 2017

Beautiful Day

-4°F (-20°C) this morning turned into +23°F (-5°C) by 5 pm! Not too shabby. After riding to College Coffeehouse this morning, I stopped by the Harley/BMW/Honda dealer for a BMW open house which translates to "free lunch". There were brats, sauerkraut and pretzels. Quite a few airheads at the free lunch none of whom were probably in the market for a new bike. I was hoping that they would have one of the new 300cc singles but was told that there was a possibility that they wouldn't even be imported due to some flack over beef. I hate politics…

Later in the afternoon, I went to the church to run sound for a youth fundraiser. It was a dessert auction and my contribution was dark chocolate chip cookies with pecans and dark chocolate brownies. The trick is not to leave with any of the delicious looking treats… 

Wednesday, March 22, 2017

Something Different


How about a non-solar post. Not bike related though I did go for a short ride earlier this week. No photos so maybe it really didn't happen…

I'm not sure why so many riders want to get here but this is the wonderful view of Deadhorse. The flight to Utqiaġvik stops here to add/remove passengers. It's usually a pretty full flight but wasn't too bad this morning. The worst part is the 6 am flight to Anchorage before switching planes to head north. I guess there isn't enough traffic in/out of Fairbanks any more. 

This is a very short trip as I'm just dragging a couple of technicians up from Fairbanks to familiarize them with the installed infrastructure that they will be supporting this summer during our road trip. 

Monday, March 20, 2017

EezTire T515 Review

The TPMS system is finally installed. It is an EezTire T515 made by Eez RV Products. It has the capacity to monitor 22 tires but I only plan on monitoring eight tires. Four on the truck and four on the trailer. I may start monitoring the spare tires later as additional/replacement sensors are available from Amazon. It came with a windshield suction cup mount and a permanent screw mount. I opted to mount it high in the cab on the overhead console so the radio signal from the sensors mounted on the trailer tires to be "seen" by the receiver.

The box included both a fused power cable that could be permanently wired in as well as one that uses the cigarette lighter socket. The challenge with the overhead console location was finding a 12 volt switched power. I ended up tapping into the power for the clearance lights on top of the cab. To get to those wires, I needed to remove the overhead console, the passenger sun visor, passenger grab handle and then partially lower the headliner. A little more than I wanted to do when the truck was parked outside. The wires powering the clearance lights are running along the passenger side "A" pillar and were easy to cut and tap into. Now the TPMS system charges whenever I turn on the parking lights, which, for me, is usually right after the engine starts.

The TPMS display unit has an internal, rechargeable battery and can be powered on using a slide switch on the side. The battery will power the display unit for up to 60 hours according to the documentation and the manufacturer recommends not leaving it plugged in all the time to extend the life of the battery. It has a motion sensor and an ambient light sensor so the unit goes into sleep mode when the vehicle stops moving and the backlight shuts off during the day. The pressure and tire readings seemed a little erratic during our cold spell and I wasn't sure if that was due to the sensors or whether the tire pressure really did change by 8 psi from just driving around town.

The sensors include these anti-theft covers. Their use is optional though the manual suggests coating the seam on the sensors with silicone if you opt not to use the covers. The "T" handles wrench is used to tighten the sensors if you use the covers. I installed the sensors without the covers but will probably put them on when the weather warms up and the roads get sloppier. The wrench is kind of a hassle as you tend to lose air while trying to install the sensors as quickly as possible. The manual also recommends a tiny bit of anti-sieze on the valve stem which I did use when installing the sensors.

I've heard too many stories of trailer tire blowouts caused by low quality trailer tires. What makes it worse is that you can't really feel or hear the blowout and when the tire starts to shred, it can cause a lot of damage. A common cause of blowouts could be under inflation or overheating. The EezTire 515 monitors temperature as well as pressure. It would still be prudent to check the tire and brake temperatures every time you stop. These days, radiant thermometers are readily available for a reasonable price.

Friday, March 17, 2017

Geeky Graph

Please excuse the geekiness of this post but I think that this is kind of interesting. Since I've had the test solar panel up, there has not really been a stretch of clear, sunny days like we've had over the last week. Whenever I checked the status of the Tristar solar controller, I never saw it go into "float", i.e. very low current and a maintenance voltage to keep the battery charged. For the temperature of the battery bank (8°C), the controller was varying the current to maintain the battery bank voltage at 13.93 volts using the "sense" wire that I had installed earlier this week. The sense wire is a 22 awg pair that go from the "sense" terminals to the main positive and negative terminals of the bank so the controller can get an accurate voltage of the battery bank unaffected by current that may be running through the cables. Another great feature of the TS-45 charge controller.

This graph is still from the data logged through the serial connection to the Windows 10 tablet as I hadn't even started messing with the Raspberry Pi to log the data. On the graph I labeled the absorption and float portions of the graph. The array voltage is orange and that is what drops to almost zero at night and goes up over 20 volts when the controller isn't needing all of the power that could be produced. The lower grey line is the current going to the battery bank and the blue line is the battery bank voltage measured on the "sense" wire.

In this annotated graph from last Sunday, we can see the bulk charging where the the controller never leaves the bulk charging mode. You can tell as the array voltage and the battery voltage track each other. The peak current from this panel is almost 8 amps. Pretty impressive performance as the panel is rated at Isc (short circuit current) of 8.02 amps. 

Thursday, March 16, 2017

Solar Omelette Take 2

The "Stone Earth Pan" (non-stick, induction ready, 12" frying pan) arrived from Amazon today. And it looks like we have a week of completely clear skies so the batteries can recharge. Almost the same ingredients except for olive oil instead of butter and I added some cherry tomatoes. The pan seemed to take longer to heat up but that could be due to its larger size. Before starting, the Trimetric monitor read -10.2 amp-hours meaning that the battery bank was still not completely charged from the crock pot test.

The ham, onions and mushrooms were partially cooked and removed from the pan. The scrambled eggs (with a little cream added) were put into the pan. After they set, the filling and some colby jack cheese was added. heat distribution wasn't even as the edges were cooking slower than the center. The completed omelette was rolled out of the pan onto a plate. No sticking at all. The stone-derived non-PFOA coated pan was non-stick as advertised and the claim is that no harmful substances are ever released.

Here is the completed omelette. It more closely resembles an omelette and I remembered to take a picture. The Trimetric read -20.3 amp-hours indicating that I had consumed 10.1 amp-hours to prepare the omelette. Peak current from the battery bank was ~74 amps when the induction burner was set to 1000 watts. I know some may not get too excited by a frying pan but the lack of a non-stick pan was preventing me from getting more use out of the induction burner.

It looks like the panel is putting out 7.4 amps on this nice sunny day. Maybe the bank will finally be back up to 100% in a couple of days.

Tuesday, March 14, 2017

Back Inside...

The Ural made it back into the garage after about ten days of being banished to the snow bank outside to make room for the truck. No issues starting up after cranking for around five seconds or so. Kind of like the carb bowls were empty and I didn't give them time to fill up while on the prime position. I should be able to start riding again on a regular basis by the end of the month.

Below zero (°F) are still being forecast for at least the next ten days so not a lot of chance of getting out much until after the first official day of "spring". Today is another clear and sunny day but the -22°F temperature still says winter though it had warmed up to 7°F by mid-day.

Sunday, March 12, 2017

More Solar Cooking

As it was still -33°F this morning (Wednesday March 8th), but not a cloud in the sky, it must be time for another cooking appliance test. The next candidate for the trip is a crockpot. In this case with a pot roast along with onions, celery, carrots, potatoes, mushrooms and a few green olives for flavor. Seasoned with garlic, thyme, rosemary, salt and pepper. The roast was browned in a frying pan so the crock pot started out warm and that may partly compensate for the 57°F garage. I started it out on "high" which pulled 170 watts according to the display on the inverter. "Low" is 130 watts according to the inverter display. Total cooking time will be about 8½ hours. Even on low it is well more than I'll get out of the one solar panel so don't expect the battery bank to be fully charged tonight. But this is something that I expect to be able to do with the four 100 watt panels on a nice day.

After almost 9 hours of cooking, the Trimetric meter showed the battery bank at 69%. It'll be interesting to see how long it takes to recharge with the single 130 watt panel. I don't think the crockpot makes the cut for use on battery power. Faster cooking even at higher power seems to be more efficient when on battery power. Plugged in at an RV park, no problem.

Thursday - Very hazy day. Not very sunny. Only 3.3 amps at solar noon and recovered to only 73% by the end of the day. Tomorrow is probably more of the same…

Friday - Overcast and light snow. Very little sun through the clouds at all but apparently there was a little bit. 74% by the end of the day.

Saturday - Sunny and visibility unlimited! No, not really unlimited but it feels that way after the last couple days of overcast. By noon, the output of the charge controller into the battery bank was 7.4 amps (98 watts!). Isc (short circuit current) for this panel is 8.2 amps. By 6 pm, the bank was up to 82%. The single panel is  able to provide about 25 amp-hours to the battery on a clear day. At this rate it'll probably take about 3 more days like today to bring the battery bank back up to 100%.

Sunday - A hazy day. Only about 3 amps from the panel.

Friday, March 10, 2017

Tonneau Cover and EB Repair

Kind of hard to take a picture of it but the tonneau cover arrived several days earlier than Amazon predicted. It is a TruXedo Truxport and it took, literally, 15 minutes to install. The intent for the tonneau is "keep honest people honest" as it is just a vinyl coated fabric. But if the tailgate is locked, you can't reach the release levers for the cover. There are four bows to provide support for the fabric evenly spaced along the length of the bed.

I had looked for one of these locally but the shops only carry the trifold variety or the aluminum or fiberglass hard covers. I was looking for a roll-up one as I would be able to simply roll it to the front of the bed when towing. I didn't want to order one until the toolbox was installed so I knew how much space was available between the sides of the bed and the toolbox lid. I also attempted to order a tailgate lock but was notified by Amazon that this item "only ships within the United States". I ended up stopping at a local vendor today and though they didn't have one in stock they could order it (free shipping). It was only $2 more but it'll be several weeks before it gets here.

Another needed repair turned out to be fairly minor. The exhaust brake (EB) had stopped working sometime in January but since I generally don't use it when it's really cold out, it didn't really matter. I figured that the air compressor had bit the dust as it has been installed for almost 11 years. The oilless compressor also didn't like running when it's cold so I had installed a relay, a switch and a dashboard LED indicator to let me know when the compressor was running. It is installed on top of the engine and you can't hear it when the engine is running. It turned out that the connectors to the air pressure switch (upper right in the picture) had simply come off.

The EB works by closing of most of the exhaust pipe using a pneumatic cylinder to close a flap inside of the exhaust pipe to create back pressure in the engine. The engine has to work against the back pressure and this slows the truck down. I have an older model and it is supposed to generate 60 bhp of braking force. It works really well as the regular service brakes are rarely used if you plan ahead (down shift when approaching a stop). The brake pads were checked last fall and the front pads are 75% of their service life left and the rear are 90%. Not too shabby for over 50k miles.

The EB is really useful when towing as you can safely descend most grades without having to touch the service brakes which prevents them from overheating. To keep the compressor from cycling every time you slow down, I installed a small (1½ gallon) air tank to the frame. Back in 2005, there were two dominant vendors of EBs one used an engine driven vacuum pump and the other an electric compressor. I figured that compressed air was more useful than vacuum. I am thinking of adding a quick release air hose connection as the pressure switch is set to turn the compressor on at around 80 psi as that is the minimum air pressure for this model of EB. They also have a 100 psi pressure switch available as an option.

I had to remove the front bumper today as the snowplow installer had pinched the winter front between the bumper brackets. A "winter front" is vinyl coated fabric that restricts air from reaching the radiator. This helps the engine warm up faster. It is usually held in place with snaps and straps. I know that this summer, I'll need to remove the winter front and replace it with the bug screen. Only one more project while the truck is in the garage. Finding power in overhead console for the TPMS system. 

Wednesday, March 8, 2017

Solar Omelette

What is to do when it's -32°F. Out of curiosity, I plugged the induction tabletop cooktop into the inverter and proceeded to make a ham, mushroom, onion and cheese omelette as that's what I found in the refrigerator. I am thinking of taking this burner on our trip this summer for use in hot weather. It doesn't generate waste heat like a regular cooktop. In the picture, the display is showing 1100 watts. Once things were cooking, it was turned down to 800 watts then 600 watts. As an example of the efficiency, the burner has been on for maybe 10 seconds at this point and the butter is already melting in the pan. Incredibly fast, convenient cooking.

The Trimetric monitor is showing that I am pulling 84.8 amps from the battery bank. I took two readings of amp-hours immediately before I started and just after I finished. At this time of the morning, there was only about 2 amps from the solar panel so minimal contribution. One three egg omelette used about 7.3 amp-hours from the battery bank including cooking the onions, mushroom and ham. This is only about 1.7% of the total capacity of the battery bank. At this point, I think that the induction burner is definitely going and is useable on battery power. Sorry, no completed omelette food pic. It stuck to the pan so it didn't look very photogenic but tasted good...

Since I like non-stick pans (less water needed for cleaning), I just ordered a non-stick frying pan that works with an induction cooktop. Any cookware used on an induction burner needs a bottom that a magnet will stick to. Most of my pans are Calphalon anodized aluminum and won't work on an induction stove. This portable cooktop included three pans as a set from Sam's Club. I don't remember the brand but it works well. A convenient mode is being able to set a temperature and the cooktop will automatically adjust to maintain that temperature on the bottom of the pan.

Here are the two readings from the Trimetric monitor. The before reading of -13.6 amp-hours and the after of -20.9. There was plenty of sun today and the single 130 watt panel brought the battery bank back up to 100% by mid afternoon.


Monday, March 6, 2017

Truck Box

This in-bed toolbox has been sitting in the garage for a couple of months. You may recognize the diamond plate as the box has been serving as my workbench. Now that the snow has melted out of the bed of the truck, I'm finally able to get it installed. Step 1 was modifying the all weather wood rack holding the 540 lbs of gravel that I have been using as snow plow ballast towards the tailgate end of the bed. These 2x4s were just braced against the front of the bed. Now they are braced against the tool box. I have some SS hardware, fender washers and lock nuts to firmly attach the box into the bed. I had ordered this toolbox through Lowe's around the end of August. Near the end of October, the store discovered that it was never really ordered. It finally arrived around the end of November. I'm glad I wasn't in a hurry.

This toolbox will be the home for the two 2000 watt Champion inverter generators when they are not in use. The two generators can be paralleled to put out 3600 watts continuous. This is enough to run the RV air conditioner if we are somewhere without electricity. And the 2000 watt generators will fit easily into the toolbox and at under 50 lbs, be somewhat manageable by myself. A single 3500 watt generator is taller than the tool box and weighs around 100 lbs. Not manageable at all. I'm estimating that the two Champions will take up about ⅔ of the toolbox. A gas container for the generators may take up the remaining space along with spare engine fluids. The toolbox is resting directly on the bed of the truck and not hanging on the bed rails like many truck tool boxes so the weight is not an issue. There is still about 1½' of space between the toolbox and the fifth wheel hitch for other storage as long as it is below the level of the bed rails.

Around the beginning of February, I ordered a roll up tonneau cover from Amazon. It was labeled Prime and I chose the free shipping option. After three weeks of the shipping status never progressed beyond "We received your order", I cancelled and re-ordered the exact same item (same vendor - Amazon) but selected expedited shipping. It was shipped the next day. What a racket...  By the way, in Alaska, Amazon two-day shipping translates to just under a week. The tonneau cover is just a way to keep honest people honest. When not pulling the trailer, I think that it might be a good idea to cover up whatever is in the bed of the truck.

BTW, winter is still hanging around. Not much else to do but wait it out. 

Saturday, March 4, 2017

More Solar Graphs

Thursday and Friday were mostly clear and sunny days. And it appears that the solar charge controller had not finished with the equalization charge that I had manually started a couple of weeks ago. I'm guessing that since the array voltage wasn't above the equalization voltage as there just hasn't been a whole lot of sun for the last couple of weeks.

This is the output from the log file from Thursday showing the battery voltage (blue), array voltage (grey) and charge current (orange). Once the array voltage got high enough for equalization to occur, current was "pushed" into the battery until the battery voltage was high enough for equalization. Most of the morning and afternoon, the charge state was either at bulk charge or absorption. The log file shows that at a battery temperature of 7°C, the target voltage for equalization was 15.83 volts and the absorption voltage was 15.30 volts.

This is the output for Friday. It looks similar at first but since the charge controller is no longer in equalization mode, the current doesn't increase beyond about 2 amps after the charger drops into absorption mode. The array voltage is just allowed to rise up to it's maximum.

What have I learned from this? I never realized how much impact temperature has on battery charging. The upper limit of the input voltage for most 12 VDC devices is 15.5 VDC. An example being the Xantrex 2000 watt inverter that I am using. I ran into a lot of comments about the Xantrex inverters when they dropped their maximum input voltage from over 16 volts to 15.5 volts. At the time I didn't know why folks were complaining. When using flooded lead acid batteries like I am, the lower battery temperature limit would be a bit above 0°F. The temperature compensated absorption charge voltage at 0°F is 14.8 + 0.75 = 15.55 volts. The equalization voltage at 0°C is 16.05 volts, well above the upper limit for many DC devices.

In other words, be sure to disconnect all DC loads when doing a manual equalization if the temperature is near freezing. Also, don't start a manual equalization unless there is enough sun for it to complete. It just means a little more thought on my part.

It's still too cold (-32°F on Friday) to do much of anything. I did drive the Ural but it was just out of the garage. The truck is in the garage so I can get some stuff taken care of.

Thursday, March 2, 2017

The Rest of the Solar Stuff

Another very long RV solar post with way more than most would care about. And another post with zero motorcycle content originally written on Sunday 02-27-2017. With the overcast, snow and cold, you can tell that I must've been bored given the length of this post. 

It has been overcast and/or snowing for the last 8 days and, not surprisingly, there was little charge to the battery bank. I checked the Trimetric monitor on Monday evening and it was reading -21.5 amp-hours and a constant draw of 100 ma. The draw was the Trimetric monitor and the Tristar charge controller. (I wonder why thing are "Tri..."?) Probably mostly the controller since I had the laptop connected to it collecting log data. The default was every 5 seconds and I just changed it to once per minute. The next week is supposed to be mostly sunny so I'll be anxious to get back to testing.

I finally finished assembling my home made combiner box and I'm pretty happy with how it turned out. In the picture, it is sitting on the 4 awg welding cable that will be running from the bus bars to the 60 amp circuit breaker to the charge controller. I picked up some flat head stainless steel screws that I could recess into the bottom of the junction box. Recessed so there would be no contact with the roofing material when the box is fastened to the roof of the trailer. I decided not to put in a ground bus bar as I may need the box space on the opposite side if I decide to install some additional panels.

I'm not positive on what the roofing material is but plan to use pieces of Eternabond tape under the combiner box and the solar panel "Z" brackets. The Eternabond tape is compatible with both TPO and EPDM flexible roofs. Dicor lap sealant will also be used to seal all of the screw holes and the 1⅛" hole under the combiner box. Actually finding the right location for that hole is the only task that has me worried. Granted, any small "test hole" can be easily sealed but I would rather just do it once. The roof cavity near the center is on the order of 8" and there is wiring and an air conditioning duct running in approximately the same area. I'm considering removing the wood panelling on a section of that wall just to see what is back there. I may be able to remove the shower faucet and see inside the wall cavity. This is something that needs to wait until I get down there.

I finally ordered most of the rest of the solar stuff for the RV. I have been tracking the Renogy 100 watt monocrystalline 12 volt panels on Amazon since November and noticed that the price had dropped in the beginning of January but was starting to creep up. There was a modest price break for a set of four panels and four was my starting point. The Tristar TS-45 PWM charge controller can handle approximately eight of these panels. (5.25 amps x 8 = 42 amps). The Renogy panels are slightly more than $1/watt and their snow load rating seems to be as good as other more expensive panels. The panels have a weatherproof junction box and come pre-wired with 10 awg wire and MC4 connectors. All of the panels will be wired in parallel to minimize shading issues.

To mount the panels, I picked up four sets of Renogy specific aluminum "Z" brackets and mounting hardware. I am not planning on making the panels tiltable but simply screwed onto the roof sealing everything with a combination of Eternabond tape and Dicor self leveling sealant. There is a measureable increase in efficiency at low sun angles but the tradeoff is simplicity. Instead of putting up with the hassle of tilting the panels, I could just add more panels.

I'm planning to run a pair of 10 awg wires to each pair of panels so I need to splice the MC4 connectors from the each pair of panels together. They make MC4 branch connectors to make the connection. Note that the connectors are different to avoid confusing the positive and negative connections. So two sets. 10 awg is rated at 0.999 ohms/1000 ft so the voltage drop with 10.5 amps (two panels in parallel at 5.25 amps) is 0.17 volts assuming 16 feet of cable (positive and negative). About 1% of the panel voltage, more than adequate.

Since I am unsure of the exact placement of the panels, I am not able to simply order a premade extension cable for each pair of panels and cut it in half. This would yield two cables each having the appropriate MC4 connectors on one end. So I ordered a 50' roll of 10 awg wire designed for outdoor use on photovoltaic systems. And a package of five pairs of MC4 connectors and an MC4 crimp tool. The MC4 connectors are designed to be "tamper proof" meaning that you need a special tool (pictured) to disconnect and disassemble the connectors. I believe that the only item left to get is the Dicor lap sealant. There was one new tube in one of the storage compartments probably left over from the roof installation.

All of this was delivered to Oregon as Amazon Prime wouldn't ship these and many other things to Alaska. But that works since the fifth wheel trailer is still in Vancouver, WA. For me, this whole process is a great opportunity to learn about solar and low voltage systems.

What did surprise me is that the crimp tools, connectors and special tool plus the 50' of cable were less than the cost of two extension cables. This way I can make them the exact length that I need plus have enough cable, connectors and tools if/when I add additional panels. For anyone considering adding solar to their RV, the total for this 400 watt system is $865.71 including the panels, charge controller w/temperature compensation, two circuit breakers, MC4 tools and connectors, combiner box, 4 awg and 10 awg wire, heavy connectors and heat shrink tubing. This total does not include the batteries, battery box, inverter, automatic transfer switch, catastrophic fuse, Trimetric monitor and shunt, crimp tool, or 2/0 awg welding cable. I would have needed those even without the addition of the solar panels. And everything is sized so I can add up to 4 more 100 watt panels. The rough "rule of thumb" is panel wattage roughly equal to battery bank amp-hour capacity. 400 watts of solar panels and 430 amp-hours of battery capacity. This "rule" is a generalization and is based on flooded lead acid batteries.

Not much else to do except start installing this stuff... That'll be in May and I can hardly wait. BTW, all of the product links are using my Amazon Affiliate link which I'm not sure even does anything.

Updated Tuesday - Today was mostly sunny and the battery bank charged back up to 100% (the Trimetric was showing +2.5 amp-hours). The specific gravity of the cells were checked and in the picture, the hydrometer shows about 1.280. To correct for the 55°F temperature in the garage I need to subtract 0.004 for ever 10°F below 80°F or 1.270 and this corresponds to an almost fully charged battery according to the chart shown below. I did check the specific gravity in all of the cells and they were all between 1.270 and 1.280 but I'm not sure how much of the variation was due to my inconsistent testing technique. There is a line near the top of the clear plastic housing and if the battery fluid was above or below the line it seemed to affect the reading. I probably should've just ordered the glass version with a float but was concerned about breakage. The forecast for tomorrow through Friday is clear and cold.

I'm logging the data to the Windows 10 laptop and it stores the data as a comma-separated text file which easily imports into Excel. The problem from my point of view is too much data. In these 820 rows you can see the sun coming up and a combination of partial clouds and the occasional tree blocking the sun. From the battery voltage, you can tell that it never made it out of bulk charge to absorption charge and eventually to float. The raw data supports that as one of the columns is control state and the entire column is "bulk". This is but a small fraction of the data as the default log frequency is every 5 seconds.