Can Induction motor run at over rated speed? ( 15oo rpm is rated speed for 50HZ. is it possible to ride 3000 RPM with same motor with the help of VVVFD for continues ride of 100HZ)3 7451
HT motors are generally connected in star, what will be the effect if we connect HT motor in Delta?6 13713
What is the magnetic field (coil DC ) of Turbo Expander?
What will happened if the neutral of the (star connected secondry) Xformer disconnected? (if its Above KVA rated one)1319
What the main causes of transient interruptions on Over-Head Distribution Lines?1199
how we can select a transformer based on a particular load. suppose we have 4 motors of rating 40 h.p , 50 h.p, 80 h.p & 100 h.p. then what rating of transformer we can select. urgent. pls reply6 16758
pls give proper discription of selection of transformer based on particular load.1 2407
How can we calculate the motor frame sizes?2511
when we are going to higher voltage level in substations why we are using Sf6 circuit breakers instead of Vacuum circuit breakers.3 3682
what is the formula to calculate the fuel consumption of a diesel generator at different diferent load.4 21695
why we used star delta starter for above 5hp motors2 5841
Hi Recently I got one formula that is Impedence of Xformer = Rated KVA/Root 3 * secondry voltage OF Xformer. Is it Right??????2 2806
Why Powers are named in MW?1 3160
Is any AC drive(VFD) had a feature of DC injection braking? if available please mention the detail. i.e drive can supply braking torque when the motor in idle state.
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?
explain different losses in a transformer.
I use 20 nos led tube 4feet, in pathway 100mtr approximate, so what size cable i use for lighting
tan delta equation test on alternators
What is mason's gain formula?
How to calculate the value of earth capacitance in a transmission line.
what is allowable ac mixing in dc
Is a contactor (or master relay) required between incoming lines and a VFD? The question goes to safety. If a contactor were used before the VFD and an e-stop engaged then the motor will coast to a stop (i.e. VFD loses power) instead of stopping much faster if the VFD braking fucntion were used. It would make more sense to keep power on the VFD.
What is Icu and Ics and what is difference b/w them. please tell me how to calculate a size of a copper bar for a system or a breaker... reply on... email@example.com would be waiting for a logical answer.
What is the form name of 'c' license, I want to download in web
whatis the commertial spec. of distribution boards ?
How one can check the MAIN of a house wiring ?
how can we make cable shedule for controll wiring ? which details must be required for it.?
How many double suspension hardware fittings are required on a double circuit transmission tower?