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Check with Locke Supply. They have a website, They have conversion charts.
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AO Smith elec water heater model EES 52 930 is this water heater glass lined?
Yes. That model has a glasslined tank.
What aspect of your performance are the most pleased with if you are elec tech?
I suppose you could answer that it was the occasion when you blew all the fuses, but then again I would expect YOUR views about what YOU did would make a better answer.
What is the difference between electrical and mechanical devices?
Electrical degrees and mechanical degrees in dc motors are related by the equation: Deg(elec) = (Number of Poles/2) *(Deg(mech))
How does an electric doorbell work?
when the doorbell button is pressed it closes a circuit and energizes the coil of a solenoid. The solenoid coil then causes a hammer to shoot out from the coil and strike a the doorbell chime.
What is the re-model of npn common base transistor?
Thus if we go back to the circuit model for the common emitter transistor, and re-draw it as a small signal model it would look something like Figure 1. Here we have replaced the diode with a linear element (a resistor, called rπ) and we have changed the notation for the currents from IB and IC to ib and ic respectively, to remind us that we are now talking about small signal ac quantities, not large signal ones. The bias currents IB and IC are still flowing through the device (and we will leave it to ELEC 342 to discuss how these are generated and set up) but they do not appear in the small signal model. This model is only used to figure out how the transistor behaves for the ac signal going through it, not have it responds to large DC values. Figure 1: Small signal linear model for the common emitter transistor Figure 1 (3.16.png) Now rπ the equivalent small signal resistance of the base-emitter diode is given simply by the inverse of the conductance of the equivalent diode. Remember, we found rπ===1qkTIB1qkTICββ40IC (1) where we have used the fact that IC=βIB and qkT=40V-1. As we said earlier, typical values for βin a standard bipolar transistor will be around 100. Thus, for a typical collector bias current of IC=1mA, rπ will be about 2.5 kΩ. There is one more item we should consider in putting together our model for the bipolar transistor. We did not get things completely right when we drew the common emitter characteristic curves for the transistor. There is a somewhat subtle effect going on when VCE is increased. Remember, we said that the current coming out of the collector is not effected by how big the drop was in the reverse biased base-collector junction. The collector current just depends on how many electrons are injected into the base by the emitter, and how many of them make it across the base to the base-collector junction. As the base-collector reverse bias is increased (by increasing VCE the depletion width of the base-collector junction increases as well. This has the effect of making the base region somewhat shorter. This means that a few more electrons are able to make it across the base region without recombining and as a result α and hence β increase somewhat. This then means that IC goes up slightly with increasing VCE. The effect is called base width modulation. Let us now include that effect in the common emitter characteristic curves. As you can see in Figure 3, there is now a slope to the IC(VCE) curve, with IC increasing somewhat as VCE increases. The effect has been somewhat exaggerated in Figure 2, and I will now make the slope even bigger so that we may define a new quantity, called the Early Voltage. Figure 2: Common emitter response with base-width modulation effectFigure 2 (3.17b.png) Figure 3: Finding the Early VoltageFigure 3 (3.18b.png) Back in the very beginning of the transistor era, an engineer at Bell Labs, Jim Early, predicted that there would be a slope to the IC curves, and that they would all project back to the same intersection point on the horizontal axis. Having made that prediction, Jim went down into the lab, made the measurement, and confirmed his prediction, thus showing that the theory of transistor behavior was being properly understood. The point of intersection of the VCE axis is known as the Early Voltage. Since the symbol VE, for the emitter voltage was already taken, they had to label the Early Voltage VA instead. (Even though the intersection point in on the negative half of the VCE axis, VA is universally quoted as a positive number.) How can we model the sloping I-V curve? We can do almost the same thing as we did with the solar cell. The horizontal part of the curve is still a current source, and the sloped part is simply a resistor in parallel with it. Here is a graphical explanation in Figure 4. Figure 4: Combining a current course and a resistor in parallelFigure 4 (3.19.png) Usually, the slope is much less than we have shown here, and so for any given value of IC, we can just take the slope of the line as ICVA, and hence the resistance, which is usually called ro is just VAIc. Thus, we add ro to the small signal model for the bipolar transistor. This is shown in Figure 5. In a good quality modern transistor, the Early Voltage, VA will be on the order of 150-250 Volts. So if we let VA=200, and we imagine that we have our transistor biased at 1 mA, then ro==200V1mA200kΩ (2) which is usually much larger than most of the other resistors you will encounter in a typical circuit. In most instances, ro can be ignored with no problem. If you get into high impedance circuits however, as you might find in a instrumentation amplifier, then vbe has to be taken into account. Figure 5: Including ro in the small signal linear modelFigure 5 (3.20.png) Sometimes it is advantageous to use a mutual transconductance model instead of a current gain model for the transistor. If we call the input small signal voltage vbe, then obviously ib==vberπvbeβ40IC (3) But ic=βib=βvbeβ40IC=40ICvbe≡gmvbe (4) Where gm is called the mutual transconductance of the transistor. Notice that β has completely cancelled out in the expression for gm and that gm depends only upon the bias current, IC, flowing through the collector and not on any of the physical properties of the transistor itself! Figure 6: Transconductance small signal linear modelFigure 6 (3.21.png) Finally, there is one last physical consideration we should make concerning the operation of the bipolar transistor. The base-collector junction is reverse biased. We know that if we apply too much reverse bias to a pn junction, it can breakdown through avalanche multiplication. Breakdown in a transistor is somewhat "softer" than for a simple diode, because once a small amount of avalanche multiplication starts, extra holes are generated within the base-collector junction. These holes fall up, into the base, where they act as additional base current, which, in turn, causes IC to increase. This is shown in Figure 7. Figure 7: Ionization at the base-collector junction causes additional base currentFigure 7 (3.22.png) A set of characteristic curves for a transistor going into breakdown is also shown in Figure 8. Figure 8: Bipolar Transistor going into breakdownFigure 8 (3.23b.png) Well, we have learned quite a bit about bipolar transistors in a very short space. Go back over this chapter and see if you can pick out the two or three most important ideas of equations which would make up a set of "facts" that you could stick away in you head someplace. Do this so you will always have them to refer to when the subject of bipolars comes up (In say, a job interview or something!).
How do you save on elec and gas without changing surplyers?
Turn things off when not using them. Get solar panels
When did Elec Ní hUicinn die?
Elec Ní hUicinn died in 1471.
Can you put an overdrive transmission in a 1981 Chevy truck that has a 3 speed automatic in it now Do you have to change rear end?
yes some trans are electronic, this could give you a problem with your computer or harness in the truck do your research .You can get elec. or none elec. I have a 4l60e there are two elec. or no elec. as far as the rear end your good to go.
Do all computers support dane elec 4gb flash drive?
The Dane-Elec Flash Drive is compatible with Windows and Mac.
What is the conductor of elec tricity?
Pure silver
Who is the finder of elec light?
Thomas Edison
What causes static elec in your hair?
friction.
1986 Mercedes 190E - both front windows and both front elec seat adjustment panels all stopped working at the same moment- the fuses are ok - what otherwise might be the cause?
Check that the wire that controls the seat adjustment has not been cut through.
Is the Frigidaire Elec. Commercial oven rated for residential use or can it only be used commercially?
Frigidaire Elec. commercial ovens are being used residentially and commercially.
What does com stand for in electrical automotive?
elec. auto
What is the best conductor of elec tricity?
Pure silver
How many valence elec trons does nitrogn have?
5
