Inside A Circuit Breaker With MikesElectricStuff | 220v Contactor Relay

With the start capacitor out of the circuit, the motor becomes a permanent split capacitance (PSC) motor in the running mode only.

Once upon a long ago I was tuning a Tesla coil I’ve built with a friend. The coil was driven by a dirty cheap spark gap made with a screw that had to be rotated to change the distance between electrodes. I had to switch off the 6kV primary transformer, ground the terminals and rotate the spark gap, repeating this procedure until the biggest possible spark jumped out of the coil. After repeating it many times, I accidentally forgot one step. I’ll never forget that moment. My arm was thrown in the direction of the wall as if it had its own will and wanted to get through. Not good. Very painful.

Optoisolators are designed so that even in failure they are capable of holding back thousands of volts. UL registration demands no less. The same is true of isolated power supplies.

The triac can handle 8 amp continuously and upwards to 60 amps in surges. But the 8 amp is if heatsinked enough. If you insist on a 15 amp capability replace the triac with a 25-30 amp model instead. But will *still* need heatsinking. I triac usually drops upwards to 1 volt, so pushing 15 amps in a triac regardless of size will generate up to 15 watts, and that will generate a *lot* of head in a hurry.

Ahh, my late, late night read of the datasheet for the MOC3041M, which the schematic initially? called out but then was changed to a MOC3041 had the mains load being carried by the MOC3041/M triac, not the BT137 triac. Good catch. The triac should still be able to handle 15 amps, not just 8. And I agree, I don’t see any heatsinking.

The one thing some users might find distracting about the Sony A33′s EVF is the RGB "rainbows" you can see when either your eye, the subject, or the camera is moving rapidly. Each pixel of the display shows its red, green, and blue information sequentially, so if the viewfinder image is moving rapidly relative to your eye, you’ll see red, green, and blue ghosts or trails around bright objects. I didn’t notice this at all until someone pointed it out to me, but after they did, it became unreasonably annoying for a while. After a couple of days of shooting with the camera, though, I again became largely unaware of it and now have to deliberately look for it to be aware of the effect.

The operation of the potential relay is based on the increase in back-electro-motive force (back-EMF) or a bucking voltage that is generated across the start winding as the motor increases in speed. The large metal mass of the motor’s rotor turning at high speeds with motor windings in close proximity has a voltage-generating effect.

The Sony Alpha A33 uses a 7.2V, 1020mAh InfoLITHIUM battery pack, with part number NP-FW50. Tested to the CIPA standard, the Sony Alpha A33 is rated at the lowest battery life among its SLT-series siblings, with 340 LCD shots, or 270 shots with the EVF. That’s perhaps a little surprising, given that it lacks the built-in GPS receiver of the A55V, has a lower-resolution image sensor yielding less data to process, a reduced shooting speed, and less buffer memory. By way of comparison, the A55V captures 380 shots with the LCD, or 330 shots with the EVF, while the A55 can manage 390 shots on the LCD, or 350 with the EVF.

That said. We routinely use run of the mill power resistors in the aluminum heatsinked package, you know the ones, they start with the letter “D”, as heaters. Ohms law doesn’t fucking care if it’s DC or AC, but a little RMS will explain that DC will do the same amount of work at a lower voltage. It doesn’t fucking matter because you can choose another resistor value and get the same thing with AC. A cheap temperature controller and a relay will suffice if you have enough thermal mass to average the temperature.

Also power the unit directly from the mains ( http://ww1.microchip.com/downloads/en/appnotes/00954a.pdf ) with the ability to power the unit directly with DC when (re)programming the ESP8266

But it’s not clear just how aggressive Flake is willing to be. On Thursday, he withdrew his opposition to a judicial nominee for the Eighth Circuit, a move he said was to balance out the absence of Sen. James Inhofe (R-OK), who was called away for family reasons, according to the Washington Post. Senators sometimes do this, as Sen. Lisa Murkowski famously did during Brett Kavanaugh’s confirmation when she withdrew her vote and was marked as “present.”

And here I am telling the tale, one reason I snort whenever the momma’s kiddies post their “safety warning” comments on HaD.