Answer / manoj kumar sahoo

A ballast & ignitor is required in MH & other lighting
fixture because its takes high voltage in starting and
normal voltage in running periods.

Answer / k.prakashchandra

They create high voltage initially to strike the arc, then
the ballast limits the current as the resistance of the bulb
becomes zero due to ionization.

IAM WORKING IN THERMAL POWER PLANT AS A TRAINEE.. I WANT TO IMPROVE MY CARRIER., IF ANYBODY KNOWS ANY COURSES., ANY TESTS, ANY BOOKS ,, ANYTHING PLS HELP ME..

2 Answers  

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why transmission voltage is 230kv and not 220kv which is a multiple of 11

1 Answers   Mettur Thermal Power Station, Siemens,

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in transformers for ex. 100mva and 400kv the secondary current is about 420 amps but for selection of bushing the capacity of selected bushing is 2000A why there is such big difference ?

2 Answers   ABB,

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?? how to calculate lighting system ????

1 Answers   L&T, Synergy,

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we r having 3 core 3 1/2, 4 core cables how we can know this cable has to be used for this purpose?

5 Answers  

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what is the method of earthing of a transformer using electrodes?

0 Answers  

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What are the various types of BUSBAR Schemes? explain each

1 Answers   NTPC,

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where to use CT and PT?

4 Answers   CEB, Reliance,

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In case of HV test on medium voltage cables, BS is asking for 4 U0 where as IEC is asking for 3.5 U0. Can any one advise me how this 3.5 times or 4 times U0 is derived?

0 Answers  

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What is a advantage of Self Reset Lockout ? On Fault breaker get trip & fault no longer exist then self reset lockout how inform us?

0 Answers   Bhad Engineers,

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what is meaning of Power factor?????????

3 Answers  

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what are the safety measures of induction motor?

3 Answers  

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