Answer Posted / nagesh.patwari

UPS systems also contain large banks of both DC electrolytic and AC polymeric film capacitors that degrade with time. The function of capacitors within the UPS is to filter out electrical fluctuations and provide clean power to the equipment being protected called “Supply Voltage Filtering” They are not static electrical components that operate in a circuit. Their design life is a mathematical function of manufacturers’ rated voltage, the voltage actually applied, the current running through them, ambient temperature, and thermal resistance. For all practical purposes, estimating service life would be based on manufacturers’ rated voltage combined with the device’s operating temperature.

Commonly at 7 year's service life span capacitor expires.

why we are not giving the zone 1 trip command to the master trip relay

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In AC if the direction of current keeps reversing every half cycle, how does it propogate through the transmission lines?

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what heppend if we are connected u1-v1-w1 as a star point in the place of u2-v2-w2 in power genration

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How we can change the direction of rotation of Induction motor? Prove it using graphical

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Explain in details how you would react to an unexpected incident when your supervisor or manager is not around to give instructions?

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How the annunciator works ? How to do its wiring

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HI....HOW CAN BE MESARED THE VALVE OF NEUTRAL GROUND RESISTOR WHIC IS LOCATED AT SWICHGEAR ON GENERATOR SIDE....

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what is interfacing in computer studies?

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we have amp, voltage, kw, length detail then how to calculte copper & alluminium size of conductor of 3-phase induction motor

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What is critical disruptive voltage?

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how do u gauge the size of the cable ?for eg. consider a 300 sqmm L.T Cable.How do u determine the size of the cable seeing it pratically?

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Why lose 1 phase voltage in 33kv to 415v stepdown transformer

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if grounding is notdone at regular intervals for long distance transmission, will the load connected at distribution end receive voltage during negativehalf cycle of the sine wave?

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1. 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 0for 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.

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I want to put this query to SENIOR & EXPERIENCED ELECTRICAL ENGINEERS. 1)I want to know about the control circuit diagrams for control panels. I found it difficult to understand. Is there ant booklet through which we can learn the circuit diagrams? 2)I want to learn about conduiting, laying cables, preparing cable schedules and various techniques which is the part of building infrastucture(construction field). I don't have any experience in this area. I have experience in control panels only. that's why i am not getting any opening in building infrastucture (construction field).Can I get the job in this field as Trainee Engineer? How to enter this field? I need job in PUNE

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