Topic :: Ohm
During the main stator winding insulation testing (phase to ground)of 11kv alternator (Lerysomer) i found 0 and resistance with multimeter and found 20 killo ohm while the power cables are connected both end (Generator & VCB). In VCB PT (Potential transformer) are connected. Please any body explain that method of insulation is correct or not? also describe of PT connections
1 2177750kva 11/415kv transformer having percentage impedence is5.64%. 11KV HV whose current 39.37A and 415V LV whose current 1043.43A.resistance is 2.5ohm. find no load loss and full load loss?
2 2246I have a reading off 1.5ohms at my mem my main c/b is rated at 40/6 amps in a domestic house and i was told to change it to a b curve c/b is this ok
11911. A 380 / 220 V r.m.s. 3-phase 4-wire circuit carries loads of 8 + j8.1 ohm; 4 + j4.1 ohm; and 2 +j2.1 ohmin the three phases respectively. The length of the circuit is 100 m, and the resistivity of the phase conductors is 0.0005 Ω/m. The neutral conductor is of the same size as the phase conductors. a) Select a reference angle 0for the first phase. Then write down the three phase voltages in both polar format and complex number format. b) Make appropriate assumptions, and take temperature effects on resistance is insignificant. Calculate the currents in the three phases. (Note: Determine conductor resistance, and apply Kirchhoff’s Voltage Law) Based on the result, suggest a main switch rating for the circuit. c) Show your preferred direction of neutral current in a diagram, and then determine its value. (Note: Apply superposition principle, and Kirchhoff’s Current Law) Use its magnitude to show that in this circuit, the unbalanced load may increase the voltage drop in some of the phases. (Note: Also observe the common volt drip in neutral) State your assumptions, if there are any. d) Suddenly the neutral wire of the circuit is broken. Estimate the new currents in the first phase, i.e. Phase L1. State your assumptions, if there are any.
1490Why we using 250ohm resistance during lab calibration and why not using in field in one plz define deeply???
1 2139QUANTUM BIOLOGY - EXAMPLE 33.3 : In quantum biology, microtubule is used to store information in a cell. At temperature of T = 300 K, measured current I in a probe is directly proportional to the supplied voltage V, when passing through a microtubule with resistance R. (a) Form an equation of V as a function of I involving k as a constant. (b) If the microtubule has R = 1 ohm at such condition, find the value of V when I = 2 A. Hint : Ohm's law. (c) Find the relationship of k as a function of R.
1 13707. A resistance of 30 ohm is connected across 240v supply. If a resistance R ohm is connected in parallel with 30ohm resistor across the same supply, the current drawn becomes triple of original one The unknown resistor R is
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How to arrange a hous hold earthing system to keep minimum earth resistance( below 7ohms).
How to arrange a hous hold earthing system to keep minimum earth resistance( below 7ohms).
if zero ohm is not adjusted on shorting the two terminal of multimeter what does it indicate
how to select the automotive wire size by mathematical calculation. for xenon headlamp with ballast. the ballast given data voltage 10-17v,current permenant 6amp, run up phase is 15amp, peak at swicth on max 400micro sec is 40amp.the sum of cable resistance is 150mohm.please provide referenc document if any for relating the peak at switch on current,time & wire wire size
1. What is differential relay? How it operates? 2.How to calculate the Short Circuit Impedance in Transformer? 3.What is the alternate solution for testing of polarity by using polarity tester while its milli ammeter does not works? 4. While testing the 33KV Busbar by using Hipot kit, what should be the test voltage we have to apply? 5. What is the procedure/activities to be taken to inject the current more than 2000A by using 2000A Loading Transformer? 6. Explain how you can give the overload setting to any Motor Protection Relay for a HT motors with formula and example? 7. Why restricted earth fault protection is needed? Why can’t differential Protection is sufficient? 8. What should be the minimum and maximum ohmic value for earthing? 9. Why DC Currents are not used in transformer? 10. What is the Frequency while we step up the voltage from 220V to 11KV? Is it possible? Explain it?
how to calculate an ohmmeter(multiple range)?.. kindly show your computatations?.... plsss answer b4 feb. 1, 2010....... it is important thing..... hope for your kindness...........
how can i check vortex shedder bar it is ok? if there is ohms condition are shown correct?
In bently nevada vibration monitoring system,what is the reason to maintain the Resistance of the probe + extension cable equal to 95 ohm? If possible explain the basic principle of measurement with detail electronic circuits.
how to find 5 kilo meter long under ground 33 kv cable fault location if IR VALUE shows 0.05 M ohm @5000 volt.and cable fault locator shows some time fault distance 3 kilo meter ,3.7 kilo meter and some time 1 kilo meter? now how to find the fault location that where is leakage. note--it is tested with 5000 kv megger and insulation resistance is 0.05 M ohm. and some time 0.03 M ohm comes.
is below 2 ohms earth resistance is good for mobile tower
1)what is the function of a frequency inverter? 2)If a few frequency inverter are connected onto a device network,what are the two setting that will ensure the frequency inverter work properly on the network. 3)whats is the name of the input sensor for weigher? 4)How to confirm that the load cellis faulty? 5)Describe briefly the steps to validate that the weigher is working properly? 6)Describe the procedure to validate the flowmeter accuracy? 7)Describe briefly the steps to validate that the tempreture sensor/transformer is working properly. 8)what is the adjustment that need to be done when you are calibrating the temperature transmitter ? 9)what are the safety measures to be taken before disconnecting motor for rewinding. 10)whats is the synchronous speed in rpm of typical 4pole 50hz motor? 11)whats is the formula for kw, ohm's law 12)if a 3phase motor is rated 3kw,415vac,what is it's rated ampere?
how we find transformer capacity by ohm
Help need in transformer !? Hello Friends The parameters of 2300/230 v 50hz t/f is R1=0.286 ohm R`2=0.319 ohm Rc=240 ohm X1=0.73 ohm X`2=0.73 ohm Xm=49.2 ohm Secondary Load impedance ZL=0.387+J0.29 solve the exact equivalent circuit with normal voltage across primery.. I know every thing but i cant find CURRENT I1=? and I`2=? Please help me give solution or only Formula please please...
what is the min and max ohmic resistance for the earthing rod installed for lighting poles for street light network
A 50Hz,4-pole,3-phase,star-connected synchronous motor has a synchronous reactance of 12ohmsper phase and negligible armature resistances.the excitation is such as to give an open-circuit voltage of 13.2kilovolt.the motor is connected to 115kilovolt, 50hertz supplying. what maximum load can be the motor torque,line current and power factor?
