New answers tagged

2

To charge a battery from a solar panel, you need a battery charger AND a regulator for the solar panel. Solar charge controllers that do both are available (make sure it works for li-ion. If you don't have a solar MPPT controller, the panel will not operate at the most efficient power point. Batteries require charging controllers to make sure they are ...


0

So I got a response from the manufacurer after sending this picture The response: "Dear, we do not recommend to connect the yellow wire with black one, it will make the inverter shell has the electricity. best regards"


1

Your diagram is wrong. Based on the labels on the photo-switch in this image. Connect battery negative, controller P- and photoswitch white wire together Connect Battery positive to photoswitch black wire Connect photoswitch red wire to controller P+ If that does not work the photoswitch may be dead.


0

Legally, Building Regulations Part P in most of the UK. Be aware that the regulations are different in each part of the UK (England, Scotland, Wales and NI). In terms of standards, BS7671 18th Edition, IEE Wiring regulations. That's not law, but it is the British Standard. BS7671 is a massive document.


1

GFCI trips are only relevant when your supply has normal Neutral-Ground bonding back at the service. So the normal way we do things, is, at precisely one point: the service point, there is an equipotential bond between neutral from supply/onward, and ground from the Grounding Electrode System/onward. The whole point of that exercise is to a) assure ...


1

Some (many?) small inverters (and Honda's "inverter" type generators) have a hot neutral. During one half-cycle, the Hot wire will go from zero to +170 V and back to zero. On the other half-cycle, the Neutral wire will go from zero to +170 V and back to zero. This arrangement avoids the need to make a negative high voltage supply, and normal loads can't ...


1

I get 120v from neutral to hot to neutral and 60v from neutral or hot to ground. The important thing to note here is that you \$\color{red}{\text{get 60v from neutral or hot to ground}}\$ This tells me that the output is likely floating BUT loosely coupled to ground with EMI capacitors of a few 100 nF. Something like this: - This means that a regular ...


0

GFCIs work by sensing the imbalance between line and neutral. If the supply is floating (like it would be with an inverter), making a path to earth wont change the line/neutral currents with respect to each other, it will only shift the floating voltage around. Tie inverter neutral to safety ground, before the GFCI, and test again. It should trip.


1

absorption coefficient is non-zero value, which implies that photons "below the bandgap" will be absorbed given enough thickness of material If the photon has less energy than the bandgap, it can't be directly absorbed. However, there are various other mechanisms by which electrons can combine a photon below the bandgap with another source of energy (a ...


0

That is a bad choice of battery. It's a starting battery, not a deep cycle battery. You'll destroy it lickety split. You may want to hang out with the off-grid homesteader / solar / wind crowd for awhile and learn how to set up systems like this. Also since you're willing to spend this kind of scratch on a battery, maybe evaluate some of those Tesla ...


0

Unfortunately your 80ms switchover time is far from "seamless" and is not likely to be sufficient in this instance, although without a specification for hold-up time for your server and switch power supplies it's impossible to say. However, for comparison, the ATX specification only says that a power supply should hold the PWR OK output to the motherboard up ...


0

That kind of "bootstrap diode and capacitor" gate driver uses a capacitor that gets floated up and connected between the gate-emitter of the high-side MOSFET/IGBT to provide the floating gate drive. But there is a catch... That bootstrap capacitor drains and need to be recharged periodically. It is normally used a half-bridge circuit where complimentary ...


1

Voltage is the difference in potential between TWO points. Any two points, not just a point and ground. You just drive the gate with a circuit that applies a gate voltage relative to the emitter, rather than ground. A so-called high-side gate drive, or floating gate-drive. Very commonly used in half-bridges. That way, you don't have to worry about the load ...


3

This is not a good idea. It may work OK if the capacitor is very small. But you will be operating the transistor in a pulse mode and you will have to refer to the peak pulse power allowable from the datasheet. It is always better to dissipate heat with a resistor rather than with silicon. Even a small resistor (a few ohms) will likely completely shift the ...


2

From offline computations, you'll have about 0.05 joules of heat storage in the silicon and the copper flag directly under the silicon, per degree C heating. If you want only 100 degree C temperature rise, then the capacitor can only store 5 joules of energy. ================================== here is the math Assume the FET is 5mm by 5mm, atop a copper ...


0

Sound like a sample and hold circuit. You can discharge the capacitor with a mosfet. Just be aware the heat will be split between the mosfet rds on and the capacitor esr. The amount of energy in a small capacitor should not be an issue. But things will get warm depending on how often. P = I2 x R, so for an accurate wattage if your conscerned you would ...


Top 50 recent answers are included