The other is a shunt across the terminals of the armature.
The magnetic shunt (which is connected Magnetic across the receiving instrument) consists of a low resist- shunt.
It is also necessary to notice that shunt instruments cannot be used for high frequencies, as then the relative inductance of the shunt and wire becomes important and affects the ratio in which the current is divided, whereas for low frequency currents the inductance is unimportant.
In the case of ammeters intended for very small currents, the whole current can be sent through the coil, but for larger currents it is necessary to provide in the instrument a shunt which carries the main current, the movable coil being connected to the ends of this shunt so that it takes a definite small fraction of the current passed through the instrument.
This shunt is generally a strip of platinoid or constantin, and the working wire itself is of the same metal.
The shunt coil Sh and the series coil Se are connected together at one point, and the remaining terminals of the dynamo and shunt coil must be connected to a " good earth," which is generally the gas or water pipes w of the building.
In instruments for larger currents the main current passes through a metallic strip acting as a bye-pass or shunt, and to the ends of this shunt are attached the ends of the working wire.
There is therefore a certain ratio in which any current passing through the ammeter is divided between the shunt and the working wire.
It consisted of a glass vessel, containing a solution of sulphate of zinc, in which were placed two plates of pure amalgamated zinc. These plates were connected by means of a german-silver shunt, their size and the distance between them being so adjusted that about ii 0 - 0 - part of the current passing through the meter travelled through the electrolytic cell and -j o i j of the current passed through the shunt.
In proximity to the upper side of the disk is placed a coil of wire having an iron core, which is a shunt coil, the ends of the coil being connected to the terminals of the supply mains.
The current in the shunt coil lags 90 degrees behind the impressed electromotive force of the circuit to be measured; hence if the main current is in step with the potential difference of the terminals of the supply mains, which is the case when the supply is given wholly to electric lamps, then the field due to the main coil differs from that due to the shunt coil by 90 degrees.
The meaning of this deflection can be interpreted as follows: If a galvanometer has a resistance R and is shunted by a shunt of resistance S, and the shunted galvanometer is placed in series with a large resistance R' of the order of a megohm, and if the same w w Se J FIG.
Since the eddy currents induced in the disk are 90 degrees in phase behind the inducing field, the eddy currents produced by the main coil are in step with the magnetic field due to the shunt coil, and hence the disk is driven round by the revolution due to the action of the shunt coil upon the induced currents in the disk.
The two coils, the shunt and the series coil, then produce two magnetic fields, with their lines of force at right angles to one another.
On setting the dynamo in operation, a current passes through the shunt coil of the ohmmeter proportional to the voltage of the dynamo, and, if there is any sensible leakage through the insulator to earth, at the same time another current passes through the series coil proportional to the conductivity of the insulation of the wiring under the electromotive force used.
The action of this bridge resembles the magnetic shunt in its effect on the received signals, as the direction of the winding is the same throughout its length, and thus the full inductive action is produced for curbing purposes.
This consists of a low resistance coil of copper wire enclosed in a laminated iron circuit similar to the magnetic shunt already de Magnetic scribed.
Any change in the resistance of the arc, either by lengthening, due to the sinking of the charge in the crucible, or by the burning of the carbon, affected the proportion of current flowing in the two shunt circuits, and so altered the position of the iron cylinder in the solenoid that the length of arc was, within limits, automatically regulated.
The tangent of the angle of deflection 0 of this needle measured from its position, when the shunt coil is disconnected, is equal to the ratio of the voltage of the dynamo to the current through the insulator.
By the use of a permanent magnet instead of a shunt coil as the bob of one pendulum, the meter can be made up as an ampere-hour meter.
a signal to take more, and at the end of the element less of the total arrival current from the cable than would traverse it if the shunt were non-inductive.
In this last case the shunt need not be contained in the instrument itself but may be at a considerable distance, wires being brought from the shunt which carries the main current to the movable coil ammeter itself, which performs the function simply of an indicator, 3.
To prevent temperature from affecting the shunt ratio, Edison joined in series with the electrolytic cell a copper coil the resistance of which increased with a rise of temperature by the same amount that the electrolyte decreased.
It is possible so to arrange the value of the shunt and of the high resistance R' that the same or nearly the same deflection of the galvanometer is obtained as when it is used in series with the battery and the insulation-resistance.
The current to be measured passes through the fixed field-coils, whilst through the armature passes a shunt current obtained by connecting the brushes across the supply mains through a constant resistance.
On the other hand the resistance of the shunt coil absorbs energy which generally varies from i to 3 watts and is a loss either to the consumer or to the supply company, according to the manner in which the shunt coil is connected.
A common source of trouble is the short circuiting of the shunt coils owing to the shellaced cotton covering of the wire becoming moist.
This rod was connected with the negative pole of the generator, and was suspended from one arm of a balance-beam, while from the other end of the beam was suspended a vertical hollow iron cylinder, which could be moved into or out of a wire coil or solenoid joined as a shunt across the two carbon rods of the furnace.
In the MIST Trial 60.2% of migraine patients had a right-to-left shunt (16.7% small shunts, 5.1% large pulmonary shunts.
In order to overcome the friction of the train the field-coils are wound with an auxiliary shunt coil which supplies a driving force sufficient to overcome the friction of the counting train.
The Ritschl school, and others too, have made an earnest effort to incorporate Christ's words in Dogmatic and no longer shunt them into systems of " Christian Ethics."
This action completed the furnace-circuit, and current passed freely from the positive carbon through the fragments of metal to the negative carbon, thereby reducing the current through the shunt.
An ohmmeter in one form consists of two pairs of coils, one pair called the series coil and the other called the shunt coil.
Its principle is as follows: Suppose there are two pendulum clocks, one having an ordinary pendulum and the other having a pendulum consisting of a fine coil of wire through which a current is passed proportional to the potential difference of the supply mains - in other words, a shunt current.
alveolustasis (collapsed alveoli) also develops rapidly in the dependant lung regions and results in true shunt.
I had the ammeter made up with a 200 amp shunt, by the helpful people at Adverc Ltd.
A shunt is resistive device used to generate a small signal voltage to display current on a moving coil ammeter.
antibiotic prophylaxis has no clear benefit in CSF shunt surgery.
The circuit model for the loop wire is therefore best seen as series resistance and inductance, and shunt capacitance.
Grease applicator: - Waiting for further information from Rutherford plus info on cooling block and shunt shield - in relation to grease applicator: - Waiting for further information from Rutherford plus info on cooling block and shunt shield - in relation to grease application.
harmonic voltage distortions at points remote from the active shunt filter itself.
hexose monophosphate shunt.
Why not shunt him into that pillar, or an oncoming lorry?
The shunt resistor is always an unusual low value, and needs to be hand-made from resistance wire.
Patel N H, Chalasani N, Jindal R M. Current status of transjugular intrahepatic portosystemic shunt.
In late 2000 he was involved in a rear end shunt on a motorway, which left him with a whiplash type injury.
shunt back into the sidings.
shunt resistor is always an unusual low value, and needs to be hand-made from resistance wire.
CSF shunt surgery Antibiotic prophylaxis has no clear benefit in CSF shunt surgery Antibiotic prophylaxis has no clear benefit in CSF shunt surgery.
shunt in the yard or see the mountain railroad in action.
waggons thought she was delivered new to Meaford Power Station to shunt coal wagons.
The amplitude of the signals can be varied in several ways, either by a shunt across the electromagnet, or by altering the tension of the controlling springs or by altering the air gap between electromagnets and armatures.
By means of a " magnetic shunt " Brown succeeded in increasing the working speed of long submarine cables to the extent of To to 15 per cent.
The use of the iron core renders it possible to produce a high inductive effect with a low resistance coil, and thus obtain the necessary slow time constant to which is due the success of this type of magnetic shunt on cable signals.
The explanation of the action of the shunt is that all slowly varying currents affect the coil of the receiving instrument and its shunt in inverse proportion to their respective resistances; whereas with the comparatively rapid variations of current used in signalling the coil is forced at the beginning of each element of A v
In those meters which are compounded - that is, have a shunt coil wound on the field magnets to compensate for the friction of the train - it is important to notice whether the meter will operate or continue operating when there is no current in the series coil, since a meter which "runs on the shunt" runs up a debt against the consumer for which it gives no corresponding advantage.
Again the shunt circuit must have practically zero inductance and the series or current coil must be wound or constructed with stranded copper wire, each strand being silk Covered, to prevent the production of eddy currents in the mass of the conductor.
On the 29th Sept 2005 I had surgery to have the VP shunt inserted.
On reaching the west end of the yard, it will then shunt back into the sidings.
Push the buttons to turn the turntable, shunt in the yard or see the mountain railroad in action.
It is thought she was delivered new to Meaford Power Station to shunt coal wagons.
Originally developed by "Roor", "shunt", and "Scar_T", PS2emu requires that you gain certain BIOS files in order to use it (SCPH10000.BIN and ROM1.BIN).
This duct or shunt normally closes at birth or shortly after.
This abnormal opening is called an atrial septal defect and causes blood from the left atrium to flow (or "shunt") across the hole into the right atrium.
For tetralogy of Fallot, tricuspid atresia, or pulmonary atresia, the shunt procedure creates a passage between blood vessels, sending blood into parts of the body that need it.
People who experience seizures, for example, may be given anticonvulsant drugs, and people who develop fluid on the brain (hydrocephalus) may have a shunt inserted to drain the fluid.
This is known as a left-to-right or aortic-pulmonary shunt.
This condition is called a shunt reversal.
Malformations associated with hydrocephalus (Dandy-Walker, Chiari II, and some cases of hydranencephaly) may be treated by installation of a drainage shunt for cerebrospinal fluid.
Although both the artery and the vein retain their normal connections, the new opening between the two causes some arterial blood to shunt (be diverted) into the vein because of the blood pressure difference.
The primary method of treatment for hydrocephalus is surgical installation of a shunt.
A shunt is a tube connecting the ventricles of the brain to an alternative drainage site, usually the abdominal cavity.
A shunt contains a one-way valve to prevent reverse flow of fluid.
In some cases of non-communicating hydrocephalus, a direct connection can be made between one of the ventricles and the subarachnoid space, allowing drainage without a shunt.
Installation of a shunt requires lifelong monitoring by the recipient or family members for signs of recurring hydrocephalus due to obstruction or failure of the shunt.
For individuals with normal pressure hydrocephalus, approximately half will benefit by the installation of a shunt.
The most common treatment for hydrocephalus is the surgical installation of a shunt.
If a child with a shunt has any of the following symptoms, parents should contact the child's doctor because the shunt may not be functioning properly.
Unfortunately, self-expression often gets the shunt when it comes to searching for something practical.
He has twice had emergency surgery and has a shunt to drain fluid from the brain.
Zach has also suffered complications from his dwarfism, and has had a shunt surgically inserted into his skull due to excess fluid.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.