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The voltage drop across a relay coil will be the same as the coil supply voltage. If you are trying to see if the coil is good or not, remove one of the voltage supply leads and check for continuity by using an ohm meter across the coil leads. A reading will tell you that the coil is intact and not open.
What else can I help you with?
How can you measure the power or voltage of a potato clock?
A voltmeter would measure the voltage. If you measure the voltage drop over a known low resistance you get a kinda-sorta idea of the power available.
Why should you be the internal resistance of the very few Amitr?
ammeter connect in series in circuit to measure the current, if the Ammeter have a high resistance it would effect the voltage value because there will be a drop voltage over the internal resistance of the Ammeter, so we desgin the ammeters with very low resistance...
What is the measure of how difficult it is for electrons to flow through a material?
You are probably looking for an answer like 'resistance' or 'resistivity', but these answers would be incorrect, because your supposition ('difficulty of flow') is incorrect .Resistance is the opposition to the drift of an electric current through a material. It's determined by the resistivity of that material, as well as by the length and cross-sectional area of that material.This opposition, however, is not a measure of the 'difficulty' of charge movement through the material. Rather, it is a measure of how well a material can support current due to the quantity of charge carriers available within the material.It's important to understand, for example, that insulators don't 'block' or 'make it difficult' for electric current, they simply don't have sufficient charge carriers available to supportelectric current.
Is there a minimum value of contact resistance of bus bar or value per joints?
You want that as low as possible. Make sure all contacts are clean and if there is high current involved I would suggest a transfer paste. Whatever you decide is the resistance is can help you calculate the voltage drop across the connection and therefore the heat that will be created. You want as little loss there as possible. The resistance will change under load. (increase)
How do you measure speaker impedance?
The real impedance is the resistance in ohms more 20%. A coil resistance of 6,7 ohms X 1.20 = an impedance of 8.04 ohms. If the voice-coil had exactly 8 ohms, the impedance would be 9.6 ohms and the sound would be unclear, tending to more basses.
Why would ignition switch relay on 2000 park avenue get hot?
Could be, Contacts have high resistance (dirty contacts), Overloaded circuit,
How might ambient temperature may affect the resistance values you would measure in a circuit?
Ambient temperature might affect the readings of the resistance value you would measure because the resistance of some materials changes with the temperature.
What would you measure to find out which wires have the higher resistance?
current
Will lower DC voltage or higher DC voltage burn out switch contacts faster if current and resistance stay the same?
if there is resistance in the contact surface , it would heat up more with higher voltage .
What is the use of resistance box?
The use of a resistance box or a "Decade Box" is to help calibrate instruments used to measure electrical values such as Voltage, Current, and Resistance. Without them you would not have a known value of resistance to use as a set point.
A measure of how strong a battery or power source is?
A good measure is its internal resistance. If the internal resistance was 1 ohm, the output voltage would fall by 1 volt for every amp of current taken. So - how low is the internal resistance? is a good question to find out how strong the source is.
How can you measure the power or voltage of a potato clock?
A voltmeter would measure the voltage. If you measure the voltage drop over a known low resistance you get a kinda-sorta idea of the power available.
How do you find specific resistance of a contact on semiconductor?
The problem that you face is that there is a resistance derived from the contact and a resistance derived from he semiconducting material itself. The trick is to separate the two resistance values. To do this you will need to set up a series of contacts. Each of the pairs of contacts will need to be separated by a different distance through the semiconducting material. I would suggest at least three pairs but the more you use the more accurate your contact measurement will be. Use a Kelvin, or 4-point measurement technique. This is done by using, as the name suggests, four probes. with two probes apply a small but known current through the contact pairs and semiconductor. Using the other probes measure the voltage difference from one contact to the other. The voltage drop, and current flow will give you the resistance across the contact pair (Resistance = Volts / Current). This gives you the resistance of two contacts and a resistance of a small amount of semiconductor. Now do this to all three different contact pairs with different spacings of semiconductor. Of course, the longer the semiconductor spacing the more the total resistance will be. If you plot these values as a line (using the spacings as an X-axis, resistance on the Y-axis), you will be able to extrapolate what the resistance would be if there were the theortical value of zero spacing, or no contribution from the semiconductor (the Y-intercept). Now this is the value of two contacts so you will have to divide this value by 2. And it is also the value of the specific area of the contact you used. The larger the area the less the contact resistance. So Divide the contact resisance by the area. The typical units to report this number is in Ohms/cm^2 (ohms per centimeter squared). By the way, this in theory could be done using less points, however you need to be aware that the linearity of your measurements is important. In practice the contacts (even good ones called 'Ohmic Contacts') are not perfect. Measuring at least three (I use five) pairs of contacts will give you a way to see if you are getting a good reading of the contact resistance. If you get a correlation coefficient, (R-squared available on an Excel spreadsheet), for your data to a best-fit line of 0.9 or better you are getting a 'reasonable' contact resistance measurement.
Why would never measure resistance in a circuit carrying a current?
If the circuit is carrying current then that means that the load (resistance) is in the circuit. if an ohm meter is connected in the live circuit then there would be some voltage drop at the ohm meter but as the meter has very less resistance, this would damage the instrument.
How can you find resistance of a component?
To measure the resistance of a component, you can use a multimeter set to the resistance (ohms) setting. Simply connect the two leads of the multimeter to the ends of the component, ensuring that there is no power running through the component. The multimeter will then display the resistance value of the component.
How test resistances?
we can measure the resistance if we know the voltage and current passing through a line (V=IR)AnswerYou can measure its approximate resistance using an ohmmeter, but ohmmeters aren't particularly accurate. A better way would be to use a Wheatstone Bridge, which is highly accurate.
Why relay contact haS two different ratings for AC VOLTAGE and DC VOLTAGE?
AnswerRelays rated for AC/DC use: the DC rating being lower than the AC, This is because DC can establish an arc across the contacts which cause the contacts to burn more,so they are rated lower.When I use relays on DC I will use double pole relays an put the contacts in series this gives a wider gap when the relay opens and helps exstinguish the arc quicker.Hope this helps. AC IS +/- WHILE DC IS JUST A LEVEL AC120 MUST WITHSTAND THE PEAK VOLTAGEReply: How is putting the two sets contacts in series going to help?The same potential is still being broken at the first set of contacts.>-------------0___0--------0___0---------->Parallel would make more sense to me, since then the current would be split between the two sets of contacts.
