17

A 240 volt motor will only be connected to the two live wires, not to neutral, so your example draws 6.6 amps at 240 volts. If it is connected to operate at 120 volts, it will be connected between one live wire and neutral, and will draw 13.2 amps at 120 volts. I think it is misleading to say that, in the 240 volt case, the motor draws 6.6 amps from each ...


14

"THIS MACHINE KILLS" WHAT YOU ARE TRYING TO DO HAS "ISSUES" EVEN WHEN DONE "PROPERLY. Here I've copied material from two comments by J: From the manual : For your safety, your log splitter is equipped with a “ZHB” control system that requires both hands of the operator. The left hand controls the hydraulic control lever while the right hand controls the ...


9

I needed a 6 uF replacement and only found a used 5 uF and a used 1.25 uF. With the help of several answers, I decided to only install the 5 uF capacitor. The motor started fine on its own. Having assembled the pump with its pumping "blades" (extra mass) and the outer case it still started fine in my workshop. Then I re-installed the 1-inch hose and the ...


9

"out of your element" .. okay. Heating elements are most of your power and 30A at 240VAC is 7.2kW. I think 240VAC/60Hz is what you want. Three phase power is going to restrict you to industrial units in many cases, and is very expensive to get installed if it does not already exist. Some commercial buildings use 208 3-phase, which yields 120VAC naturally, ...


7

An AC motor which uses a start capacitor will exhibit this behavior if the capacitor is not connected; it is possible that this motor has a centrifugal switch, which should start the motor by connecting the capacitor until spinup is achieved; dirty contacts on such a switch will make it hard to start, and sometimes just hum. The centrifugal switch will be ...


6

I think a Half-Wave Rectifier is what you mean.


5

After more research was done I confirmed my initial doubts of the statement quoted from the Microchip Application Note which states that a direction of motor rotation at startup can be set by the direction of the current produced by the phase-generating H-bridge (or in other words by the polarity of the energized stator coils). Simple answer is - it is not ...


5

how do the home appliances (using AC) and electronics (using AC as rectified to DC) continuously function (inspite of periodically recieving 0 current)? A full wave rectifier and reservoir (smoothing) capacitor are used to "hold-up" the voltage during the time that the AC is close to zero volts: - It acts like a water tank - if the main water feed into ...


4

There is NO problem with the neutral conductor remaining connected. Most electrical codes REQUIRE the neutral to remain connected between the main (grid) supply and the backup supply. Also note that the neutral conductor is bonded to earth ground, usually at the meter socket. Be aware that most electrical codes require the use of a transfer switch between ...


4

This is assuming North American 120:120 wiring. Suppose you plug an extension cord into the outlet, then run it back to the spot in the house. Also suppose you have a voltmeter rated for safe mains operation and know how to use it (if that's not true, get assistance from someone (friend, neighbor, licensed electrician, whatever) who does know how to do ...


4

This site is not meant to be for appliance repair. However - things re motor design and operation may be able to be learned from this. Understanding what is being tried here and what may be wrong and how to try to be sure can be an immensely valuable learning exercise. "Just doing it" without understanding misses a major learning experience. The following ...


4

You have to stop the motor before you can reverse it. That lets the starter winding establish the new direction (and if the starter winding is disconnected by a centrifugal switch, it lets the switch turn on again.


4

If you have a single-phase three speed split capacitor motor, the following will explain your readings: simulate this circuit – Schematic created using CircuitLab Numbers in Green are calculations, which correspond to your measurements.


4

I believe that @StainlessSteelRat has presented a pretty likely configuration for the "Run" coil and the speed selections. I suspect that the white wire is connected to an internal capacitor that is connected in series with the "Auxiliary" coil. That would be one explanation for infinite resistance between the white wire and the other wires. If all that is ...


4

If you need 3-phase, 208V for just one 3-phase motor, you can buy a variable frequency drive (VFD) that will accept 120 V, 1-phase input and provide 208V, 3-phase output and control the output voltage and frequency to provide variable speed. It is simple in the sense that you just buy a single product and connect it. You should be able to easily select a VFD ...


4

how do the home appliances (using AC) ... Because motors have inertia: When you spin a motor using single-phase AC, the torque goes to zero when current goes to zero. The actual torque being transmitted from the windings to the armature is roughly sinusoidal at twice the line frequency (so, 120Hz for a 60Hz line frequency). The motor spins because the ...


4

Thermal overload relays are sensitive to the heating due to current flowing in the heater elements. The thermal sensing element in a three-phase overload is calibrated to trip based on the current flowing in all three heaters. If only two heaters are used, the overload will have a lower temperature for a given current, so the trip level will be higher than ...


4

If safety is of any concern, than NO you cannot use a single pole switch. Your current switch is a four-connection AC switch. This datasheets has a wiring diagram for a similar switch I used in a recent project: http://cdn0.grizzly.com/manuals/h8243_m.pdf The AC source is likely connected to a driver board or internal rectification inside your motor, if ...


3

Most single-phase equipment will work fine on three-phase, assuming all other necessary specs are met. You just connect two of the three legs. The load doesn't know there's a third leg and two more phases running around the universe somewhere, any more than your 110V blender knows there's a 220V outlet that your dryer is plugged into. (If you're not in the ...


3

If you have access to internal connections between the coils, you can reverse the motor by reversing the connection of one coil with respect to the other one.


3

Place a high resistance (perhaps 1M ohm) from your + to - output. Now there is a closed circuit which includes 2 diodes and a resistor. Where is the source in that loop ? (You didn't say you wanted voltage to GND) Then you edited in a capacitor, which is ok. LT Spice simulator might or might not be trusted. Along with seeing no source in your loop, ...


3

A single line to ground fault on a three phase supply causes the phase-to-neutral voltage on the un-faulted phases to rise. The voltage rise depends on how your three-phase system is earthed. Unearthed systems will have high voltage rise under fault; effectively earthed systems have lower voltage rise under earth fault. Let's say that you live in Australia, ...


3

It is written in a confusing way, but well. The one phase motor has only one phase from which something is drawn, the other one is bound to ground. You use a one phase motor because you don't have three phases. That means using phase-phase voltage on it wouldn't make sense, you should be using a three phase motor instead. The 120V vs. 240V is not related to ...


3

You can think of it this way: the motor is using the same amount of power regardless of the voltage. From your formula, you know that since the voltage doubled, the amount of current flowing through the wires and motor must have halved, since the power is the same. This is also the reason devices that are switchable for 120/240 volts use a fuse with half ...


3

Two capacitors in series is half the capacitance. Try three in series or one 0.5 uF capacitor. Reducing the capacitance reduces the available torque and allows the load to slow the motor down. At some point, the motor may not have enough torque to start reliably or may vary a lot in speed while running. At that point, you will know you are trying to reduce ...


3

The resistive component of a generator output impedance comes largely from the physical resistance of the windings. How you model this is up to you. Usually we deal with systems intended to have a fixed voltage. In that case, it is useful to model the generator as a voltage source with the inductance and the DC resistance in series. That's the Thevenin ...


3

A reverse phase dimmer does not have a triac but an IGBT or MOSFET. Such a dimmer contains also the electronics needed to modulate this device. These electronics can be simple or very complex. The principle is simple. The mains AC is fed into a bridge rectifier with in the centre the IGBT or MOSFET. The IGBT or MOSFET can be switched on and off at any ...


3

The portable generator is designed primerally to provide a 110V center-tapped earth supply as is normally used on UK construction sites. The 230V output is something of an afterthought which is why you end up with it referenced to earth in a weird way. In the standards for modern appliances in Europe there is no expectation that the "neutral" pin is at ...


3

First I must repeat that I know nothing about motors! However, knowing that most capacitors like that have a tolerance larger than 17%, I would just use the 5 µF. When they originally selected a capacitor with 6 µF of capacitance they knew that it could have a large manufacturing spread. Of course, maybe the original one had more than 6 µF, and maybe the ...


3

There isn't enough information to figure out exact AC voltage or current. You will have to assume a value for V or I. You could graph I for a range of V=100-120. That will give you a reasonable range of possible values for I taking possible voltage sag into account.


Only top voted, non community-wiki answers of a minimum length are eligible