Recent content by wheisenburg

This is a trace from this weekend's test. From 10:00 to 1:30 the graph shows string 3 running and string 2 cycling on and off to supply the load from my dryer and other heavy loads. Even with this 5000 watt load running, it can keep the battery between 94 and 100% SOC. The dryer is not a steady...

Well I did more testing today. Based on prior testing I adjusted the load shedding so that string 1 sheds at 92% SOC and reattaches at 90%. String 2 sheds at 97% and reattaches at 94%. String 3 is now always connected. The AC Coupled Frequency Shifting can manage the 3 KW output of string 3...

I know it is standard industry practice to use 12-2 nonmetallic cable (better known as romex) for 240 only circuits. So you get a white and a black. Using the "correct" color isn't really an option. Running 12-3 just to have the right color is not required by code. The code may require using...

I'm not sure it's code, but I consider it a good safety practice.

I was having issues with the battery voltage going to high and causing the micros to turn off. I probably should have 6 batteries rather than 3 with close to 10 KW of PV. Thats 190 charging amps. The system can handle this at 90% SOC. At 97% SOC the high voltage shuts theinverters off...

No, but you do need something to: Disconnect your microgrid from the grid. Act as the grid forming inverter. Capture the excess power coming from the micro inverters and send it to the batteries. Perform frequency shifting to lower the output of the micros to prevent over charging. A hybrid...

This is nit picky and you will find many panels where this is not done, but when using a 12-2 Romex cable for a 240 volt only circuit (no neutral needed), you really should "Redesignate" the white wires using red electrical tape. This makes clear in the panel (and even more important on the...

Mostly this is true so long as you do not have a current measuring device on the wires like a CT. In that case mixing up the polarity will cause the device to measure incorrectly. For example on the Enphase combiner box getting the polarity of the wires correct is very important. Multiple...

On the Schneider ALL the neutral lugs are internally tied together. Generally you would have a "First means of disconnect" upstream of the Schneider. In this case where you are feeding a panel from the Schneider the ground neutral bond should really be upstream from the Schneider not in the...

I need to know if there is a 200% / Hz profile that is IQ8 compatible. I found an "Off Grid" profile that is supposed to AC Couple with Schneider, but it says it is compatible with the IQ7 family only.

My Settings: Nothing Special here. AC Coupling On Recharge SOC 95 - Doesn't seem to make any difference Battery Type - Custom Charge Cycle - 2 SOC Control - Enabled works better with SOC Battery Bank Capacity - 300 Ah Maximum Charge Rate - 60% If the actual charge rate when AC coupling...

Thanks, I checked and I do have the latest firmware.

I think there are at least three reasons. It is higher voltage (up to 600 volts). DC tends to sustain arcs better than AC. A short in a PV circuit is less likely to trip a circuit breaker or blow a fuse. So if these wires arc and burn up, the metal conduit is more likely to contain the fire...

I sure seem to remember that the IQ8 inverters were ramping up slowly before the recent firmware upgrade. Possibly, the ramp up had been over ridden in the firmware. A part of the firmware "fix", may have been to remove the override and respect the ramp rate (or lack of one) in the grid profile.

I will do that. I will also go through any information I have on how some settings seem to affect the operation of AC coupling.