Tuesday, September 19, 2023

Time for solar electric upgrades

Time marches on. So does technology. Old and new technologies don’t always work well together. 

My solar electric system was pretty cutting edge -over 20 years ago. There have been a few upgrades since. The first upgrade was more solar panels. Then I replaced the old electro-mechanical charge controller with an electronic one. It was expensive but made for a big jump in efficiency. 

One of the original parts still in service is a Trace 2425 modified sine wave inverter. That’s what turns the DC battery storage power into regular house AC. Modified sine wave has some downsides. One noticeable problem is a buzzing on audio equipment. There are a few electronics that don’t work at all. Electronic chips that use sine wave patterns as part of the timing really have a hard time. Some things just burn out. 

However, most things work just fine on modified sine wave power. Even compact florescent lights worked well. Those were bleeding edge technology when my system was first installed. 

The problem is those florescent lights have been replaced with LED lights. LEDs do not work well with modified sine wave. They are dim and tend to burn out -which isn’t great. 

Fortunately, true sine wave inverters have come a long way. Unlike in the old days, they are readily available and pretty cheap. 

I’ve got one on order and it should be here in a few days. I’ll let everyone know how that works out in the real world.



  1. Looking forward to the report.

    I still have a modified sine wave in the faraday can. Should just buy a sinewave for that backup.

    1. Modified works well enough for many things. Mine has been pretty much bullet proof, and that's not nothing.

  2. Mine's true sine wave and rock solid. Any electronics plugged in just work, period. Wasn't cheap per se, but that's a small price for ease of use. Can output 4KW continuous or burst up to 10kW (great for welding). Had a modified swine wave inverter before and it did screwy things with laptop and battery chargers. All my lights are 24VDC LED strips, straight off the DC buss, so no inverter involvement there.

  3. Dweeze, Model of your sine wave please?

    So many on the market, some with what seems bogus "reviews" others seem ok.

    Pricy thus the request for recommendation.

    BTW Open request to anybody who has real life experience with a current sine wave inverter.

  4. Selectronics SPMC241 - made here in Australia. Their hardware is pretty much bullet proof (company of old school engineers). Their software interfacing is rubbish (see above). This is an older model but, afaik, the hw in the newer ones is still chonky. Good luck.