The switch-board is designed to handle these various voltages and to communicate them to the apparatus under test in Building No.
Our terrestrialvoltages are baffled by an air-gap of a few inches, but lightning springs across a gap miles wide.
It is usual to consider that the phenomena of residual charge and heating in condensers, to which alternating voltages are applied, are closely allied.
If we are determining the voltages of various cells by a comparison of the respective currents produced, the result will be true only on condition that the resistances in the various circuits are equal.
But two voltages of equal value do not give equal currents unless the resistances met by the currents are equal.
The primary wires of the transformer are attached to the service wires in the house and from the secondary wires voltages are taken to suit the desired purposes.
The miniature lamps are similar in action to other incandescent electric lamps except that they are operated on voltages lower than is used on commercial circuits.
Different classes of work require different amounts of current at different voltages and by choosing the proper combination of series, multiple, or series-multiple connections practically every requirement can be fulfilled.
These transformers are also used to supply current for lighting low-power tungsten lamps that cannot be used with the ordinary voltages employed in house lighting.
Still lowervoltages may be used with filaments suited to the quantity of light desired.
The coils between contact 1 and the others 2, 3 and 4, represent different number of turns of wire and in them is induced voltages corresponding with the number of turns of wire in each.
Sometimes household voltages are more hazardous because people underestimate the dangers involved.
You can get these low voltages by using one or more batteries, or by using a transformer connected to your house current.
Diagram of single phase transformer having primary and secondary windings in two sections, showing voltages per section with series connections.
The relation between the alternating and direct current voltages varies slightly in different machines, due to differences in design.
The change in commutator voltage for constant collector ring voltage is in virtue of the property of rotary converters that the ratio of these two voltages is a function of the width of the pole arc.
Several taps are provided to take care of different voltages and wave forms.
Diagram of single phase transformer with primary and secondary windings of two sections each, showingvoltages per section with parallel connection.
These outdoor transformers are of the oil immersed, self-cooling type and have been developed to meet the requirements for transformers of capacities greater or of voltages higher than are usually found in distribution work.
The various relations that could exist between thevoltages and currents of the grid of a vacuum tube, and the values which do exist between them when the tube is in operation.
How the Positive and Negative Voltages of the Oscillations Act on the Electrons (C) Fig.
Inductance coils or condensers or both which (1) prevent troublesome voltages from acting on the different circuits, and (2) smooth out alternating currents after they have been rectified.
In wireless it is used for changing commercial direct current into direct current of higher voltages for energizing the plate of a vacuum tube oscillator.
How the Positive and Negative Voltagesof Oscillations Act on the Electrons.
The meters usually are voltmeters and ammeters, the former being adapted to read the several voltages of direct currents in the power plant.
When higher voltages are required in order successfully to operate the circuit, it is generally customary to install a telegraph repeater circuit at the center of the line, in order to keep the voltage within safe limits.
Taps for different high and low pressure voltages can be readily provided at the time the transformer is being built.
At still higher voltages corona spreads to further distances from the conductor and a greater volume of air becomes luminous.
This method gives correct results even with considerable unbalancing in the voltages of the three phases.
This method is of service, only, provided the voltages of the three phases are the same.
When the voltages are equal and the machines in phase, the difference of pressure between a and a given point is the same as that between a' and the same point; this obtains for b and b'.
In the manufacture of most measuring instruments, the graduations of the scale are made at the factory, by comparing the deflections of the pointer with voltages as measured on standard apparatus.
The engineers to whom the operations of the cable had been intrusted had decided that very high voltages were necessary to its successful operation.
He also calculated that very high voltages would be necessary, and the practical difficulties involved made it seem certain that such a system would cost far too much to construct and to operate to be profitable.
For similar separations, the ratio of striking voltages between carbon blocks and metal blocks respectively is as 7 to 16.
Where power is valuable and the distance over which it is to be transmitted is great, such high voltages are justified by the economics of the power problem.
With care not to use them at voltages beyond their ratings, lamps will last for years.
There are a number of portable batteries on the market suitable for such service, at voltages ranging from 6 to 32 volts.
When one goes into higher voltages, it is necessary to change the type of dynamo to alternating current, so that the current can be transformed to safe voltages at the point where it is used.
Then I'd run various voltages and varying frequencies through the plastic.
Voltages higher than 550 are not considered in theater work.
They can be obtained in voltages ranging from 2 to 250 and may be operated in series or in multiple.
The auto-transformer is a very useful device but on account of the fact that the high voltage exists in all of its parts, it is not safe to use with the high commercial voltages outside.
The National Electrical Code classifies all voltagesbelow 550 as low.
The nearer equal the primary and secondary voltages are, the greater the saving in copper in the secondary coil.
Nevertheless voltages above 220 should not be considered in the auditorium, stage, or dressing rooms of any theater.
The traveling show must also be prepared for different voltages and a suitably arranged group of resistances is very convenient in this respect.
In the case of direct current the only method available for working such low voltage lamps off higher supply voltages is to arrange the lamps in series.
Accordingly, connections are provided to the voltmeter switch such that the attendant can compare the voltages at the dynamo terminals and bus bars before closing the dynamo switch.
When sounds vibrate the ribbon extremely low alternating voltages are developed at the ends of the ribbon, which has a very low impedance of only 0.
The difficulty experienced with bipolar machines is that, with a dynamo of large output, the speed at which its armature would have to rotate to generate commercial voltages would be excessive.
How then can commercialvoltages such as 100 or more volts be obtained with a self-exciting dynamo?
And recently, as a further refinement, we have been able to capture internal brain voltages and use them to reproduce thoughtlike sensations.
Now, it is this combination of physical sensation voltages and internal brain voltages, when fed into your brain from a simple tape like this, that produces what we call Electronic Living.
When but one of the machines is running, the idle machine is brought up to speed with the main switch open, and the voltage regulated by means of the rheostat and voltmeter until the voltages of the machines are the same.
The result gives the ratio between the voltages of the testing set battery and cell being tested respectively.
To measure high voltages it is necessary to connect the voltage across high resistance and to measure on the potentiometer a definite fraction of the total drop.
An arrangement of carefully standardized resistances for measuring voltagesin comparison with a standard cell.
This operation repeated with any number of different cells, will give their voltages in terms of the voltage of the testing set battery, and from these ratios their relative values may be readily obtained.
When the machine is started, the combined voltageswill probably be able to send sufficient current through the shunt to excite the machine.
Polyphase meters indicate the average angle between the currents and voltages and are superior for polyphase service to meters having only one current coil.
For voltages below this the horn gaps cannot, with safety, be set close enough together, out of doors, to take advantage of the freedom of discharge of the electrolytic element.
Single phase motors may be connected to either or both phases, but in such cases, no load should be connected between the outer wires otherwise the voltages on the different phases will be badly unbalanced.
What voltages are ordinarily used on two phase lines of more than moderate length?
This device may be connected in series with the motor leads for voltages up to 2,500; it is designed with an inverse time limit device which may be adjusted to give the desired protection.
To prevent serious unbalancing of voltages in Edison three-wire systems causing trouble, differential balance relays are used to trip the circuit breakers on a small percentage of unbalancing.
It is well known that with transformers, operating on high voltage lines and having large ratios of transformation, there may occur, on the low tension side, momentary voltages to ground greatly in excess of the normal.
This problem is entirely separate and distinct from that of eliminating the tendency toward short circuit, incident to the high voltages now common in transmission lines.
Each coil is provided with several taps so located that a number of sub-voltages may be obtained.
These relays operate with a low current reversal at full pressure and conversely with a proportionally greater current at voltages less than normal.
The generation of the radio-frequency current is by large-powered tubes which are operated with high voltages in their plate circuits.
It all depends on the characteristic of the tube as we are operating it, and that depends not only upon the type and design of tube but also upon what voltages we are using in our batteries.
Illustration: Fig 123] The highvoltages which are used in the plate circuits of these high-powered audions are obtained from generators instead of batteries.
With a view to this, it has become increasingly common of late years to publish not the voltages actually observed, but values deduced from them for the potential gradient in the open in volts per metre.
It is thus futile to compare the absolute voltages met with at two stations, unless allowance can be made for the influence of the environment.
The first method limits the possibilities of the homopolar machine so greatly when large currents and high voltages are required that it is now only used in rare instances, as e.
These cables form independent circuits and enable the voltages at the distant end of the feeder to be read at the central station.
This is the reason why considerations of economy dictate the use of the highest voltages possible in long distance transmissions.
Since the space AB includes the same number of armature coils as space FE and they are in fields of equal strength, the voltages across the two spaces will be equal, and the voltage over AB equals that over FE.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "voltages" in a variety of sentences. We hope that you will now be able to make sentences using this word.
