The Chinese Connection

It’s been a while since I reported on the Solar Powered Rainwater Project. Since that early-April post, I’ve been gathering the rest of the parts, and we took our annual trip to the Red Power Roundup — this year at the Iowa State Fair in Des Moines. The biggest part of the delay was waiting for the solar inverter charge controller. I wasn’t thrilled with the delivery delay on the device, but it turned out well in the end.

Choosing the right solar inverter charge controller is one of the most important decisions in an off-grid system.

The Ideal Thing

Anyone who has used Amazon or eBay to order product from China has probably experienced the longer shipping times these Chinese products frequently have. Air shipping is expensive, and if you can wait for container shipping, the cost is small and often zero. The inverter/charge controller was ordered from Sun Gold Power in Shenzhen, China through Amazon. As I mentioned in an earlier post, The device combines a 4000 watt inverter, 40 amp MPPT charge controller, battery charger and A/C transfer switch in one package. It can be used off-grid, grid-assist or as a uninterruptible power supply (UPS). It even has provision for a backup generator. This is a very convenient product, and I was unable to find anything else like it in American product offerings. Unfortunately, there was very little information online and no product reviews in the Amazon store. I contacted the company directly through their Web site, and they responded quickly to my request for a manual. A good sign.

Ordering the Solar Inverter Charge Controller

The product manual is reasonably good and answered many of my questions regarding how it would work in my application. After sizing the system and deciding on an off-grid approach, I was ready to order.

The 4000-watt inverter was capable of producing a 12,000 watt surge for 20 milliseconds — hopefully enough to get the 2000-watt inductive load of the well pump started. In spite of sparse information from other customers, I decided to order one.

After placing the order with Amazon, I quickly got an email from the company. They wanted to confirm the choices I had made, and I was glad they did. I needed 240 VAC, split-phase output, and had inadvertently ordered 120 VAC instead. That would have been disappointing! They didn’t have the specific model in stock but would be making them in about two weeks. Would that be Ok? One more thing: the next production run would be for orange cases instead of blue. Was that a problem? That was fine with me, but perhaps they could speed up the shipping? Yes, and for a little extra cost ($55) they could ship 3-day by air with DHL. I paid the extra shipping and the deal was done. In about three weeks I would have a shiny new device.

This may take a while . . .

I got a product shipping notice from Amazon and the arrival date was more like six weeks in the future. Well, I had experience with variable arrival dates of Chinese product before, so I didn’t pay much attention. I was busy with other projects and didn’t need it right away.

Three weeks passed with no delivery. Checking the Amazon site, it showed my product in transit, but the shipper could not provide detailed information on the product location. Again, I had experienced this before, so no problem. Four weeks passed and then five, and I was starting to be concerned. I emailed the company again, and was relieved to get a quick response. Yes, they had shipped the inverter, unfortunately they had shipped it to the wrong customer. No wonder it wasn’t here! It was time to think about cancelling the order. Through emails to the company, it became clear that a mistake had been made, but they intended to make it right. If I could wait just a little longer, I would get the product. I gave them two weeks to get it here, or I would cancel the order. They said they would, and would sweeten the deal with the free addition of a battery temperature sensor (BTS, a $40 value).

All’s Well That Ends Well

Well, to my surprise and relief, the inverter/charge controller arrived two weeks later. It was carefully packed inside of wooden panels as advertised on their site, appeared to be in perfect condition and included the BTS. I wouldn’t be able to test it until we got back from the Red Power Roundup, but I now had the most important piece of the system.

If you’re sourcing a solar inverter charge controller, confirm specifications carefully and be prepared for delays when ordering overseas.

Next:batteries and putting it all together!