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10

As for the first article, although the date isn't clearly mentioned, it dates from 1911 apparently. Wordage has evolved since. As for the second article, it is written by a French person (Eric Brasseur). In French, especially in academics, voltage is most often referred to using the word "tension". "Voltage" in French sounds awkward, just ...


9

I'm going to refer to voltage as "tension" throughout this answer. The English word "tension" (in the electrical sense) is much older than "voltage," and it was probably used long before scientists were able to formulate a clear definition of tension. Alessandro Volta certainly had some idea of tension. A handful of sources on ...


5

The absolute maximum input voltage is min(VDD, VDDA, VDDIO2, VDDUSB) + 4.0 with some notes. It does not appear to me that it's safe to apply 5V to the pin if min(VDD, VDDA, VDDIO2, VDDUSB) < 1V. In other words, supply sequencing may be necessary to ensure that the 3.3V supply is not absent with the 5V supply present. (Or, you could just use a level ...


5

If your optical encoder has a pull-up resistor on the phototransistor collector, adding only one resistor can solve this issue. Here, we can calculate the R as, $$ \frac{R_c}{R + R_c} = \frac{3.3}{5} $$ $$ R = 0.52 \times R_c $$ If your device requires very low power consumption, the external resistor will draw some constant currents. In this case, ...


4

Your MCU has built-in ESD protection diodes on the pins, so you could just use those to clamp the voltage. Since they are designed to only protect the device during handling for assembly, you need to put high value resistors in series with the line to limit the current through those diodes and to not overload the driver. Sizing of resistor should be low ...


4

Typically Delta is used for 3 wire distribution and 4 wire Star is used for industrial to have both 120, 208V single and 3 phase power loads. Residential uses split phase 120/240V sometimes misnomer called dual-phase but more appropriately called dual-line L1, L2 and Neutral. Anything we can say is 0V and is low impedance is called "ground" which ...


4

Concepts The first thing you have to get used to is that GND/Vss doesn't exist. There's a completely unrelated thing called earthing or safety grounding which is (as best possible) referenced to the dirt around your structure. It is a safety shield and never, ever carries current (except during fault conditions obviously). Here are 2 more concepts: AC power ...


3

Your table seems to be mostly correct. The breaker requires one pole for every hot wire. The word "polarity" doesn't apply and is not used to describe the number of poles on a circuit breaker. Poles and polarity are two entirely different things. The word poles is used for the number of magnetic poles in a motor, but polarity is not. The word ...


3

Complementing other's answers, even the term "voltage" is used imprecisely. What we associate with that term is more precisely described as "voltage difference" or "electric potential difference". Since in most practical applications the voltage is measured against a local reference, the difference in usage of the terms is ...


2

Using : $$ \ RC\frac{\mathrm{d}i_2}{\mathrm{d}t} + i_2 = -i_1 $$ $$ RC\frac{\mathrm{d}i_1}{\mathrm{d}t} + i_1 = -i_2. $$ Add equations $$ RC\frac{\mathrm{d}(i_1+i_2)}{\mathrm{d}t} +(i_1+i_2) = -(i_1+i_2). $$ Or $$ RC\frac{\mathrm{d}(i_1+i_2)}{\mathrm{d}t} +2*(i_1+i_2) = 0. $$ One can solve vs (i1+i2) ... and then obtain separately i_1 and 1_2.


2

Shift encoder output to MCU input voltage range? Your encoder datasheet shows that the output of the encoder is CMOS compatible, so it will be active pullup and pulldown. The easiest way to level shift is to use an N-chan FET, though you must remember that this will invert your signal. Set your Launchpad input pullup resistor on. For the voltage translation ...


1

"connecting the load and the battery" ... uh ... usually the load determines the current. As long as the wire has much less resistance than the load, decreasing the wire's resistance any further has minimal effect. Now there's nothing wrong with your 2 ohm example as long as you understand that the wire itself IS the load ... as in an electric ...


1

Perhaps calibrating LDR light-versus-resistance is unnecessary... Think of maintaining a constant light level, be it from daylight or LED source. Thus, the LDR will be maintained at a fixed value of resistance. LED will provide all the light in darkness, and no light during daylight. LED provides some light during day/night transitions. This might be ...


1

Most N-Mos Mosfets need the gate voltage to be 10V higher than the source voltage to be turned on. If you want the source voltage to be 9.6V then the gate voltage must be 19.6V. But your Mosfet has no part number for us to see its Vgs specs.


1

I’m not sure what equipment you have available, but a sync-check relay (like this one) would only allow the generator breaker to be closed when the voltage magnitudes and phase positions on both sides of the open breaker are within narrow windows. Get somebody that knows what they’re doing to set it. By adding more complexity you can use a synchronizer. It ...


1

Here is a schematic for the case of sensor can't be floating. If input protection needed, see How to protect microcontroler analogue 0-5V input pins from high/negative voltage The voltage V5 (Vreference, offset) and resistor R4 can be changed if needed. Gain set with R2 = 1500 (Vinput V3 from -10V -> 10V, output full span (0 -> 3V).


1

Datasheet page 31, part 10.1.1. It says, The fully-differential voltage input of the ADS111x is ideal for connection to differential sources with moderately low source impedance, such as thermocouples and thermistors. Although the ADS111x can read bipolar differential signals, these devices cannot accept negative voltages on either input. And also as you can ...


1

The ADC is supplied with positive supply and ground, so it cannot be used to measure negative voltages below ADC ground. The ADC inputs have protection diodes to power supply pins, and as the current is limited by the resistors, the protection diode to ground starts to conduct and that is the reason you have only -0.7 V below ADC ground at the input pin.


1

The reason for this is that you can't apply negative voltages to this ADC. Its input voltage must always be 0V or larger. If you apply a negative voltage, the ADC's input protection diodes will start to conduct and clamp the input voltage to around -0.7V. You have to add an offset to the input voltage if you want to measure negative voltages, i.e. by adding ...


1

Your biggest concern when using a small motor as a generator won't be getting too much voltage or current. Your problem will be getting enough voltage and current. My son has a small steam engine. Not that model, but one like it. It produces more power than your home made steam turbine is likely to. We built a generator from a small motor and used it to ...


1

For just one LED, you can use a current limiter circuit built from 2 transistors. Here's an example (simulate it here): More here: Controlling High Current LEDs with an ATmega328


1

You can put two zeners back to back, in each direction the voltage will be the zener voltage of the reverse biased diode plus the forward drop of the forward biased diode. If you need to get zeners in LTSpice with different voltages you can make a new model using AKO (A Kind Of) to change a parameter of an existing zener model like this: .model zlowlimit ako:...


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