Most reacted posts

It's not the DC current up one and down another of the three lines of the three-phase transmission line that's an issue. The three lines run close together and pick up essentially the same voltage along their length, like a twisted pair (they are actually a twisted threesome, essentially the...

As to what happens to the "overflow": It heats the panels, but doesn't damage them. If the controller rejects the power by no longer loading the panel, the electron-hole pairs that would have provided current recombine in the semiconductor material, releasing the energy as heat and infrared...

The telephone company equipment standardized on 48V batteries back in the start-up days of telephony. The voltage was chosen because, up to a little over 48V, if you touch it you can usually let go and get away with maybe a tingle but no serious burn, internal damage, or heart rythm issues...

I'd run the wires under the trailer and supported periodically so they don't droop. But I wouldn't put the major lines - Solar to charge controller, charge controller to battery, battery to inverter (or charge controller and inverter to battery), in any kind of "protective" covering. (12V...

That's my understanding, yes. Typical transmission lines run AC currents per-phase-conductor in the 750A ballpark during normal operation and the largest ones are rated a bit over 4,000A. The DC drift to hysterical voltages of elevated wires with no DC path to ground due to the atmospheric...

As others have pointed out, you really need to precharge (for SECONDS) with the resistor to prevent catastrophic damage to the inverter's circuit boards, wiring, and the switch contacts from massive overcurrents as the giant capacitors are suddenly charged from giant batteries. When you connect...

Thanks. I stand corrected. (My post was from my light reading of the online manual when it was announced.) I've since found the diagram on one of Will Prowse's videos: about 4:48-4:52) It wasn't hooked up AT ALL like I thought. I thought the two supplies were fed 120V by being hooked from...

This isn't just about small units being less efficient than large (which they aren't to such a great extent.) This is an absorption refrigerator. That means it effectively acts as both a heat engine to convert heat flowing across a temperature difference into mechanical energy in the form of...

Propane tanks are normally installed with plastic pipe underground and the transition to metal pipe most of the way up the vertical run where it exits the ground. It will have a metal wire run along it but with the end hairpinned just before the end of the wire, with the loop several inches...

If you have two (or more) 18Ks in a parallel configuration, can you configure them for genny on one (some) 18Ks and Smart Load on (the)other(s)? Also: can you have different smart load setpoints on different 18Ks in a parallel configuration (with the smart load/genny ports not tied together...

Just cranked up the Harmon pellet stove a little farther at the townhouse on the east side of S.F. Bay. Not solar there and moving out soon anyhow so won't be. Place was 60F this morning and two minor bumps of the setting only brought it up to 70, so one more... Any more of this global warming...

Things I'd try at this point: 1) measure the voltage across the terminals of the cells them selves, both individually (no need to unhook them from the rest of the assembly) and as a group (from the most positive end to the most negative end of the string, "inside" any circuitry between them and...

Well... The conclusions are right but I'd phrase it differently. Confusion arises because the two lines are at opposite phase, so if power IN on L1 is current IN, power OUT on L2 is ALSO current IN. Total current on L1, L2, and N has to be zero, so the current contributions from...

Specfically: - MUTUAL inductance between the two halves forces the current from transferring power between L1 and L2 to be equal and both the same direction (and in N to be twice that and in the other direction), while: - TOTAL inductance forces magnetization current (the bulk of the current...

I'd bet that's a "yes". If so, I wonder if they'll apply (all or some of) the tariff to storage systems containing Chinese BMSes. If not, it's another strike to US domestic battery manufacturers vs. foreign competition.

It's an ordinary 3-phase panel fed from a 240V "high-leg delta" utility feed. The neutral is fed, not from the midpoint of the phase triangle, but from the center-tap of one (the "lighting") pair of phase legs. So while those two are at 120V from neutral, the third ("high") leg is at 208V. By...

I don't know about inspection requirements. But T-class fuses can be a source of fire, so I'd be inclined to put them in one or more metal boxes, with as little else in them as possible, to protect the house and as much equipment and wiring as you can. See above for fuses. I think it's not...

For a test - or a short-term emergency recharge from the line - you could pull the cover of your breaker panel, stuff in an extra 240V breaker pair (or substitute it for a temporarily unplugged load, such as a stove or an adjacent pair of 120V breakers for things you can spare temporarily), and...

Unless one of the others is MUCH closer to your solar panel site, or it doesn't have a good location for more boxes and a rack of batteries, convert the one with your most important, must-keep-them-up-in-a-grid-outage loads first. Preferably use a grid-interactive all-in-one such as the new EG4...

Also: it won't be a significant issue unless you ground those many miles away panels. The two wires for each string run close enough together that they might as well be a twisted pair as far as solar storm frequencies are concerned. If the miles of wire from your panels to the charge...

Or feed the pair 240V from your drier outlet. (Install another "drier outlet" for it, or a direct feed from a 240V dual-breaker of whatever capacity you want to provide, with suitable wiring, conduit, etc. later.)

Sorry, I typoed that. 3/4 kW is what I meant to type. (745.7 is within 0.58% of 750, so it's convenient for thinking about kW vs HP.) Thanks very much for catching it

Do you have enough room for two of 'em? If so, consider two 24V batteries in series for 48V. There's lots of 12 and 48 volt equipment available, as they're standards for automotive and telephony infrastructure respectyively. Also: EVs are switching to 48V for accessories in upcoming...

Note that the Chargeverter is only rated for altitudes up to 1500 m / 4921 ft (See the specs on the last page of the install/operating manual.) This may be important if you want your installation permitted or your fire insurance to remain valid.

Nah, they just made the sun arrive at work an hour late, moving that hour's production to the afternoon. You'll have it back by the sun's quitting time at sundown. B-)

Because one form of nerd humor is to take a joke literally and deadpan extend it one or a few steps further. Sometimes it gets progressively more hilarious the farther you go. Eentually it usually runs into the ground, so you have to pick a good stopping point. (Go short if you're working...

as I understand it, here are some things that might have affected it: - The low temperature already noted (higher panel output voltage and lower wiring resistance than standard conditions) - Extra light reflected in from around the direct path (from scattered clouds when your panels aren't...

Perhaps the Nest devices were dependent on house line power and that had failed when the flaw in the power system started, sufficiently before the devices could detect the fire that they were no longer operating, or no longer operating well enough to communicate and make alarm sounds.

Same here AND have a site a tad over 5,000 feet altitude. (5,020 feet / 1530 meters at the equipment location.) (One problem I have with the EG4 equipment is the max altitude specs onmost of it, which eliminate most of California starting just east of the Central Valley, along with nearly all...

Two or three decades ago, when solar panels cost an arm and a leg, adding a tracker to get a 40%ish boost from a couple panels was a reasonable deal. But solar panels are semiconductor electronic devices and their price/performance curve has followed a version of Moore's Law, dropping like a...