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What else can I help you with?
When checking resistance does the power have to be off?
Short answer: yes. Most modern multimeters will not be damaged by external power when measuring resistance. But they will give erroneous readings. It is best to remove the power and disconnect the measured resistance from the larger circuit. A multimeter determines resistance by applying a small voltage, and measuring the resulting current. If the resistor has an external voltage source, then it will interfere with the measurement. Furthermore, if the resistance is connected to a larger circuit, then the resistance of this larger circuit will also be involved.
Why it is advisable to remove the source and complete the circuit by internal resistance or by a link instead of short circuiting the terminals of the supply?
Because many electronics, like power supplies, have internal energy storage in the form of capacitors. If you were to short the terminals, you would be shorting out the internal capacitors and thus creating a potentially hazardous situation. "Completing the circuit by internal resistance" allows the energy stored in the internal capacitors to bleed off slowly because the internal resistance is larger than a short.
What voltage would you expect to measure across closed switch?
Original Correct Answer:The voltage across an open switch should equal the supply voltage.More Detailed Answer:The above answer is basically correct. However, it may not be EXACTLY the supply voltage.This is counter-intuitive at first glance and confuses a lot of people, including electrical engineers. The reason is this. Voltage, Current and Resistance are all interrelated by Ohms Law. Voltage equals Current multiplied by Resistance.It is easy to think that since a switch is open, then you do not have current flow through the circuit. Thus, current times any Resistance is equal to zero volts because the current is equal to zero. Thus, by this logic, you would expect to find zero volts across the switch. In actuality this is true.But, when you insert you meter, you change the conditions of the circuit, and the following is the result.Let's say that you have a circuit with a resistance load like a heater, and a inductive load like a motor. The switch that powers these devices is open, thus their is no current flowing through the resistance or inductive loads.Now you put the meter across the open switch. When you do, you insert a very large resistance in parallel to the open switch. Why? Because to get volts, the meter measures current flow through a known resistance, and then calculates voltage. To keep the resistance from impacting the circuit performance, the resistance is very large. Therefore, when you insert the meter, you will get a flow of current through the meter.Because of this large resistance, the current trough the resistance load, inductive load, and wires is very small. Thus, the voltage drop across the loads and wiring is very small. Therefore, it appears that the entire voltage in the circuit is across the huge resistance in the meter. The result is a voltage reading that is very near the source voltage.Let's do the math. Let's assume you have 120 volts. You also have a resistance of 500 ohms, and a motor winding that has 0 ohms resistance when DC is applied (This is true for motors). The meter has a 10 million ohm resistance.If these loads are in series, the total resistance is 10Million 500 ohms. The 11.9 microamps. By multiplying the current flow to each resistance, you get 6 millivolts across the resistance, no voltage across the motor winding, and 119.994 across the open switch or meter. Since a meter rounds it reading, you would get 120.If the loads are in parellel, you would get the same thing, becuase the switch is in series with both loads. In this example, the motor winding would have all the current flow through it since it is zero ohms, and the parallel resitance load is 500 ohms. Thus, the total resistance is the 10 million of the meter, and this resistance drive the current, and thus the largest voltage drop is at the swtich/meter. You could decide to remove the motor from this parellel circuit. If you did then the then the result is the series circuit above.
Susan remove the motor in circuit which increase the current how it affects bulb?
lol
We have a problem with induced voltage. We measure 220 VAC in the L and 45 to 60 VAC in the N. There is no chance of changing the cable. How to avoid this?
Normally the neutral wire of every circuit is connected to the neutral bus bar in the main breaker panel. Because the neutral bus bar is always connected to ground you should never be able to measure any voltage between the neutral wire and ground.So, if you are measuring 45 to 60 VAC between the neutral and the ground it could be that the neutral wire has become disconnected at the breaker panel or somewhere in between the panel and the point where you are measuring that voltage.Assuming the load equipment - an appliance, a motor or whatever - is still connected to the hot and neutral wires, then, if there is no connection to the neutral going back to the power station, in effect you are measuring the line voltage from the hot feed as reduced by the resistance and/or reactive impedance (total reactance) of the load. That could be making 45 to 60 VAC, as read by your meter, appear on the neutral wire coming back from the load.A simple way to prove if that is the case is to unplug or disconnect all loads - appliances, light fixtures, motors, etc. - from the circuit in question. If you cannot then measure any voltage between the neutral wire and ground the next thing to check is the resistance between the neutral and ground.First of all switch off the circuit by switching off the breaker at the main panel - or remove the circuit's fuse if it has a fuse and no breaker - and then use the resistance range on a multimeter to measure the resistance between the neutral wire and ground. If it is a very low resistance then an open neutral is not the cause of your problem. If it measures as a very high resistance or an open circuit then your problem is an open neutral.The reason for the open neutral must be found and that fault must then be corrected urgently.In the Discussion page to this question please let us know what you found when you did the tests suggested above, and whether or not this advice helped you to locate and fix this problem.To be able to help you better it is important to know exactly here this circuit is located geographically in the world and to have confirmation whether - as inferred from your question - it is a 50Hz system with one 230V live and one neutral or whether it is actually a 60 Hz system having two 120V hots (+120V and -120V) balanced around neutral.Then, if necessary we shall have to consider what other reasons could cause the fault you have described but to be able to do so it would help to know exactly what you found when you did the tests described above.As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.Before you do any work yourself,on electrical circuits, equipment or appliances,always use a test meter to ensure the circuit is, in fact, de-energized.IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
How do you change the blower motor resistor in a 2001 Chevy prism?
Remove the glove compartment. Its behind it just to the left of the Blower. Disconnect the connector with four wires on the bottom. Remove two hex head screws, also from the bottom. I used a 7/32 socket to remove them. Remove resister. The resister looks like a small circuit board with printed circuit traces on it. Install new resister in reverse order.
When the resistor removed from a parallel connection of the circuit whether the resistance increase or decrease?
if we remove a resistor from the parallel connection the effective resistance value will be increased.
How do you calculate thevenis resistance in thevenis ckt?
First,remove all current and voltage sources ie replace voltage source with a short and keep current source open.Now draw the equivalent resistance-only circuit and find the equivalent resistance as viewed from the terminals of the circuit.
How do you change the blower resistor on 99 CHEVY S-10?
Open hood, locate resister on passenger side of firewall, unplug the electrical connection, remove the three screws and remove resister.
When checking resistance does the power have to be off?
Short answer: yes. Most modern multimeters will not be damaged by external power when measuring resistance. But they will give erroneous readings. It is best to remove the power and disconnect the measured resistance from the larger circuit. A multimeter determines resistance by applying a small voltage, and measuring the resulting current. If the resistor has an external voltage source, then it will interfere with the measurement. Furthermore, if the resistance is connected to a larger circuit, then the resistance of this larger circuit will also be involved.
When determining the thevenin equivalent circuit Resistance?
To determine the Thevenin equivalent resistance (Rth) of a circuit, first, you need to remove the load resistor from the circuit. Next, you can deactivate all independent sources: replace voltage sources with short circuits and current sources with open circuits. Finally, calculate the equivalent resistance seen from the terminals where the load was connected, which may involve combining resistances in series and parallel as necessary. This value represents the Thevenin resistance of the circuit.
What is common to both thevenin and norton theorem?
To solve any D.C. circuit by using Thevenin Theorem,First of all load resistance RL is disconnected from the circuit and open circuit voltage across the circuit is calculated (known as Thevenin equivalent voltage)Secondly, the battery is removed by leaving behind its internal resistance. Now we calculate equivqlent resistance of the circuit ( called Thevenin equivalent resistance).Now we connect Thevenin Voltage in series with Equivalent resistance of the circuit and now connect load resistance across this circuit to calculate current flowing through the load resistance.Whereas in the case of using Norton theorem, we again remove the load resistance if any, and then short circuit these open terminals and calculate short circuit current Isc.Second step is same as in Thevenin theorem i.e. remove all sources of emf by replacing their internal resistances and calculate equivqalent resistance of the circuit.Lastly, join short circuit current source in parallel with equivalent resistance of the circuit. Now, we can calculate votage across the resistance which was connected in parallel with Isc.So, by knowing the open circuit voltage, we can calculate current flowing the resistance and on the other hand , by knowing the short curcuit current , we can calculate voltage across the resistance.
Where is the blower resistor located on this vehicle?
There is an upper footwell panel on the front passenger side of the car. Remove the trim panel. This exposes the blower motor assembly. Find the electrical plug on the unit and unplug it. This will expose the resister screw and by removing the screw, you will be able to remove the resister for the blower. If the resister does not show continuity when tested with an ohm meter the resister needs to be replaced. If the resister shows continuity the problem may be the blower motor relay. Hope this helps on your 1998 Mystique.
How do you remove a defroster resister in a 02 Chevy s-10 rear wheel drive pickup truck?
Not sure what a defroster resister is, need more info please.
Where is the blower motor resister located on a 1996 Chevrolet 2500?
The blower motor resister block is located in the center of the dash. Remove the complete glovebox and look to the left and you will see it...............
How do you change a blower resister on a 2000 Chrysler Sebring JXI?
Behind the glovebox there is one panel to remove, then use a small socket to remove the two screws holding in the fan resister card and connector. You will need to lay on your back to do this using a light source.
How do you replace the rear blower motor resistor on a 2002 Chevy Trailblazer?
Remove the HVAC rear module auxiliary assembly.Disconnect the electrical connectors from the rear blower resister auxiliary.Remove the air outlet duct from the rear blower motor controller auxiliary.Remove the screws from the blower motor rear resister auxiliary.Remove the rear blower motor resister auxiliary.Replace the resister and install new thermal gasket.................
