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.