Answer / ashok

for traction application we preferred dc series motor.
becas its starting starting torque is high

Answer / subramanyam

Voltages used are 1.5kV DC and 25kV AC for mainline trains.

Calcutta had an overhead 3kV DC system until the '60s.

The 1.5kV DC overhead system (negative earth, positive
catenary) is used around Bombay (This includes Mumbai CST -
Kalyan, Kalyan - Pune, Kalyan - Igatpuri, Mumbai CST -
Belapur - Panvel, and Churchgate - Virar). There are plans
[2/04] to change this to 25kV AC by 2010. In preparation
for this, BHEL has been retrofitting some EMUs with AC
drives to allow them to operate with both DC and AC
traction as the system conversion proceeds. Conversion to
25kV AC has already been done on the Titwala-Kasara
section; next to be converted are Khapoli-Vangani, Vangani-
Thane, and Titwala-Thane. The Madras suburban routes
(Madras-Tambaram in the '60s, extended later to Villupuram)
used to be 1.5kV DC until about 1967, when it was converted
to 25kV AC (all overhead catenary supply). (This is where
the MG DC locos were used, e.g., the YCG-1 series.)

The 25kV AC system with overhead supply from a catenary is
used throughout the rest of the country. The WCAM series of
locomotives are designed to operate with both DC and AC
traction as they move towards or away from the Bombay DC
section. The new [2003] AC-DC EMU rakes used in Mumbai are
also designed to operate with both DC and AC traction as
the Bombay area switches over to the 25kV AC system. Read
more about Mumbai area electrification.

The Calcutta Metro uses 750V DC traction with a third-rail
mechanism for delivering the electricity to the EMUs.

The Calcutta trams use 550V DC with an overhead catenary
system with underground return conductors. The catenary is
at a negative potential.

The Delhi Metro uses 25kV AC overhead traction with a
catenary system on the ground-level and elevated routes,
and uses a rather unusual 'rigid catenary' or overhead
power rail in the underground tunnel sections (Line 2).

How can claculate to attain the desired PF in the line ( HOW Much KVAR is required ) Pls Give the formula? Equate Petrochemical 0 1 how to calculate sizing of NGTR (Transformer rating,Loading resistor value and Current rating of resistor) and what is the X/R ratio. Details : 11kV,Capacitance 1.73532 micro farads,40kA for 1sec. 0 1 What will happened. if we feed 3phase supplay to the stater with out insert the rotor. How much current will flow through the stater winnding? Equate Petrochemical 0 1 What is required of exietation to the alternater. 0 1 why star point of HT motor not earthed? Equate Petrochemical 0 1 Why we are getting low voltage in star connection? Equate Petrochemical 0 2 What's ND relay & it's functions? Equate Petrochemical 0 2 How instantanious short circuit current is calculated? its formula? Equate Petrochemical 0 2 What is servo Motor? What's the advantages of this motor over Induction motor? Equate Petrochemical 0 2 What is core CT & it's function? Equate Petrochemical 0 3 what is meant by star/delta voltages as 440/220 in a 3 phase induction motor, and why it should be connected on STAR IN 3 PHASE SUPPLY L & T 0 4 What is required of exietation to the alternater. KNB 1 23 what is the design voltage for 6.6KV 2000 KVAR HT capacitor? Consultancy 0 3 Pls explain about vfd control?Where it is used, Give some example? siemens 1 22 Please explain me abt PQ diagaram in the power sector. 0 9

0 Answers  

---

what is "pu" in electrical engg.

4 Answers  

---

how many power plants in andhra pradesh,how many types and there capacity

2 Answers  

---

whether energy meter is connected in series or parallel.why?

2 Answers   Encom,

---

How to test lightning Arrester?

0 Answers  

---

how we can adjust for three phase motor cold stall time ,hot stall time and thermal register set up?

0 Answers   OPS,

---

ro plant grundfos bm30type pump.we start the pump using siemens 3rw 4423-1bc44, 30kw soft starter. bur its failier frequently. so we planed to change the dol starter. sp please tell me any budy its possible or not翿შ†

1 Answers  

---

Two bulbs of 100w and 40w respectively connected in series across a 230v supply which bulb will glow bright and why?

0 Answers  

---

we all know that both the generator and motor are electromechanical conversion devices.....then why we rate motor in kw and generator in kva????

4 Answers   KSEB,

---

what is the opencircuit tes &short circuit test in transformers ,why you need this test, in poen your connecting which votmeter why?

1 Answers  

---

What are the limitations of Kirchoff's laws?

0 Answers  

---

What is the meaning of Dyn11 of Transformer.

17 Answers  

---