Musings

Combating Ignorance (My Own)

A couple months ago I had a “crisis”(?) with the power system for the barn.  I made it through most of the winter just fine, invariably shutting down the system on my way down for supper and turning it back on in the morning to save the power that would have kept the system up overnight.  Suddenly the power accrual fell off the cliff and I really got concerned.  A day that should have been inputting 300-400 watts into the system was instead producing 70, or 50, or even 20.  Since I had a generator wired into the system last year I was not at risk of being without power while working but the dysfunction was not insignificant despite the fact that I seemingly had enough power to work in the shop all day.

I trouble shot every aspect of the system I knew, even getting so desperate as to READ THE INSTRUCTION MANUAL (even my pal BillR who is an EE and MS Robotics guy says the system product information is almost impenetrable).  In desperation I corresponded with Rich, the EE who sold me the system, and BillR, who installed the solar components.  They too were scratching their heads about the situation.

Then at about the same time they both had a suggestion: make sure the Dump Load switch is turned on.   The Dump Load is a resistance coil to “dump” any excess electrons once the batteries were charged to full capacity to prevent them from being damaged by over-charging.

Yup, that was the ticket.  Apparently during one of the evening shut-downs I absent-mindedly (or at least inadvertently) threw the Dump Load switch to “off” and left it there.  The Dump Load switch is right next to the switches for the inverters.  With the Dump Load off the system would literally only accept the trickle necessary to keep the batteries topped off.  So, when I saw the system first thing in the morning and last thing in the evening, where no meaningful consumption was ongoing, the system had told itself to choke off any wattage input from the solar panels to protect the batteries.  During the day when I was using electricity the system would have shown an input equal to my usage but I would not have seen that.

In the moments following my turning the Dump Load back on I literally let out a whoop as the input went from 20 watts to almost a kilowatt because throwing that switch told the system to go full bore.

So I didn’t really have any kind of crisis, other than the one in my own mind due to the fact that I did not understand fully the intricacies of the power system, even after all these years.

Good thing ignorance is curable.