Tuesday, November 5, 2024

Changes done

The changes mentioned in the last post have been completed. 

In addition, two three-to-one solar cable splitters have been replaced.

The new relay card will arrive mid-November.


I'm looking for software scripts to SSH into the RPi and program the Triron. I found some but the Boost Duration and Equalize Duration registers cannot be read or written to correctly.

UPDATE:

The relay card has arrived.

The LiTime LiFePO4 12V/100Ah battery has replaced the 12V lead-acid battery. More on the lithium battery, later.


Monday, November 4, 2024

Mechanical and Electrical update with possible future software updates

Two basic mechanical changes will have been made:

1. replacing the temporary round aluminum tube with Superstru half channel.

2. lift the array several feet off the ground.


Two electrical changes:

1. replacing the existing, underrated card with a more suitable card.

2. The duracel batteries are being replaced by LiTime 12V/100Ah LiFePO4 batteries. Communications over a couple of weeks with agents of LiTime and Epever plus extensive online searches, has resulted in a usable set of parameters for the Triron-LiTime pairing.

Future software change: The Dygraph software may replaqce the existing hml graph.

 The array framework has long needed some modifications. Some of the originlal work was haphazard and only temporary in intent. Yesterday and today and tommorrow will have been spent making the needed changes. The array is also being raised higher off the ground. There have problems with the lawn grass wilting under the lower end of the array. The new arrangement will leave the bottom of the array several feet off the ground. A five foot section of pipe was attached to the existing pipe using a junction/coupler. The most needed change is the replacement of temporary round aluminum tubing as a base for one of the panels. Superstrut half channel is the replacement and matches the rest of the framework.

The wench used to raise the array onto the pipe, originally, is being used to lift the array several more feet. The wench had to liberally oiled to overcome friction. The pipe clamps on the pipe were also oiled to make the lift easier. One additional benefit of the lift is the full west facing tilt available to catch late afternoon sun.

A new relay card is on the way. The recent card worked when underated. That was good luck. The replacement did not last so long.  The reason turned out to be the ratings of the relays used. The ads stated 12V, 24V which I assumed was the working load voltage. I was wrong. The relays are marked 14V, which is why they failed with a 24V/13A load.


Tuesday, July 23, 2024

Programming the RPi

 Each time I've had to start programming a Pi from scratch, there've been two ordeals to overcome:

1.) Compile the driver for the charge controller and

2.) Program the Pi for WiFi Access Point operation.


Variables:

1.) The model: 3b+, 4b

2.) The opsys: Jessie, Buster, Stretch, Bullseye, Bookworm

3.) The program code source

All can effect the result. As time passes inevitable incompatibilities arise and have to be reconciled. Thus, I am attempting a period setup. The term 'period' is borrowed from the world of entertainment media, e.g., period clothes, period furniture, etc.. I attempt to match the software with the operating system that I have been successful with. The model may have less impact. The installation software, Raspberry Pi Imager, automates some of the work.

Currently, I have the system up and running except for a csv to image script. I'm looking at alternatives like gnuplot and matlibplot.

I expect a motor control module in a few days. The unit seems perfect, except for the use of relays in place of MOSFETs.


Friday, July 5, 2024

RPi and obsolescence

 Attempts to get my system up and running have failed, so far.

The software has changed with each update, from Jessie to Buster to Stretch to Bullseye to Bookworm. The Exar driver has always been difficult to install, but now the driver will not compile.

I have two options. Wait till someone solves the problem or revert to an earlier version of the opsys, namely, Stretch or Buster.


Friday, June 14, 2024

Inverter/generator disaster.

 A couple of months ago, I was using the generator alone, with some electrical tools and disconnected from the house. The Predator 2000 was running as usual when I heard a loud slapping-banging noise.

I ran as fast as I could to turn the thing off. By the time I reached the generator, the noise had gotten louder and a thrashing noise had started. I turned off the machine and the engine chugged to a slow stop.

The coiled spring-loaded strap in the recoil starter assembly had come loose and damaged the motor and surrounding space. I ordered a new rope starter assembly and a new ignitor. I installed the parts and decided to adjust the valves while I was at it.

The unit did not start. The compression has improved but there's no spark getting to the cylinder as far as I can tell. There is one other part that may solve the problem: the ignition coil.

Now, Harbor Freight calls an 'ignitor', what most would call the 'ignition coil'. And calls an 'ignition coil' what most might call a 'pick-up coil' or 'sensor coil' mounted deep inside the generator. Their 'ignitor' is mounted outside and on the motor housing and plugs onto the spark plug electrode, as in a car.

My guess is the machine will run if I replace that part they refewr to as the 'ingnition coil.'

I've been in no hurry since, as quiet as the generator is, I enjoy the silence and zero gasoliine costs I save by not running the thing daily. But, I will evetually need to get the unit running for Winter.

Lightning strike!

 Several months ago, a lightning storm occurred. During that storm, a bolt struck my solar array framework. The array was not adequately grounded. A steel cable connects the array to the house, outside, and is used to support the electrical wiring that runs from the array to the control center inside the house.

Subsequently, when the bolt struck the frame, the cable acted as an electrical conductor. The lightning jumped from the outside metal wall fastener to the system iniside. There was a flash of light from the storm's bolt and a smaller flash inside the house along with a loud pop sound.

The lightning blew out the charge controller and damaged the inverter. The batteries, two, did not last long after that.

The charge controller was replaced by a better version from the same company, used but cheaper. 

The inverter was a stroke of luck purchase on eBay. The unit has an automatic sitch inside that detects an existing line voltage. This makes transistioning from generator to invereter/batteries easy and automatic. Prior to that, I had to manually connect and disconnect power cables.

I added a bolt and washers to connect the cable to the array frame. This creates a direct path to ground for lighning.


Wednesday, October 25, 2023

Battery charger damage and repair

  An old Schumacher automobile battery charger has been used to charge the system auto batteries , for several years. One day, a couple of weeks ago, the charge went pffft. When I tried to plug the unit into the wall a grinding noise was heard. I took the thing apart. The construction was surprising. There are two button diodes used as rectifiers. One had shorted. I replaced both with standard through-hole tech diodes and reassembled the unit. Functional status restored.