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Under-voltage, PV safety and Tiger Woods in AEE Solar Dealer Conference

I spent the end of last week in sunny Phoenix Arizona at the 3rd Annual AEE Solar Dealer Conference. Emphasis on sunny, as I had to shed 3 layers of clothing upon arrival, after flying in from the freezing East coast.

AEE is one of the industry's largest distributors in the US and this conference is their way to strengthen their dealers’ network in an enjoyable setting. The objective is to give their customers an opportunity to get 3 days of valuable training on general subjects like safety, codes, and how to develop a solar business, in addition to training about specific products and advanced solutions to everyday problems faced by installers.

It is all nicely done in a relaxed atmosphere with plenty of socializing opportunities and fun activities in between. Although it is only the 3rd year running, it seems many of the participants come year after year, building a tight and loyal community.

One of the highlights was a full-day training on US coding by Bill Brooks. It was my second time attending Bill’s classes, which are always both very educational and entertaining. The US is very unique compared to the rest of the world, in terms of heavily relying on building- and electric-codes to verify the safest PV installations. For example, much effort is made to ensure that all wires are properly protected with fuses against any over-currents and a 600VDC limit is strictly enforced. One of the things mentioned by Bill was that in the efforts to avoid OVER-voltages and passing the 600VDC limit, UNDER voltage conditions are overlooked, becoming “the endemic problem of PV installations in the US”. Installers and system owners tend to disregard the fact that voltages of DC modules are reduced over time due to aging and that performance of many inverters deteriorates over time, especially in hot days, due to this under-voltage phenomenon.  Following this, the SolarEdge booth was overloaded with installers asking how our fixed-string voltage mitigates this problem (since you asked… it solves this problem completely because the input voltage of the SolarEdge PV inverter is never dependent on the number of modules or temperature!)

Another interesting topic was the risk of fires due to arcing on DC wires. Arcs are created when DC current flows through broken or exposed wiring. The draft of the NEC2011 code has a section mandating that all new PV installation will have a mechanism to detect arcs and disconnect its flow. But it seems this amendment concerns many in the industry since not many solutions exist that meet its requirements at reasonable cost.

SolarEdge will present in the coming months its solution to the arcing problem, demonstrated in the following movie: when an arc is generated, the power optimizers which are embedded in each panel, automatically detect it and shut down. This stops the arc before it becomes hazardous and prevents it from re-occurring.

I was there to offer 2 training sessions on the SolarEdge products. It was a pleasure to see how the SolarEdge solar power harvesting solution fits so nicely to what affects and limits installers these days.  In the first session of training I was in a small class going head-to-head with Bill Brooks. In the following day I was going head-to-head with Tiger Woods speaking on TV. In both times I was happy for the many that chose to attend my class:)