Answer / ankamsreekar

Electric motors frequently have space heaters (or strip
heaters) installed to prevent moisture condensation in the
motor during times the motor is not running.

Many motor manufacturers use metallic or ceramic cartridge
heaters for this purpose. Because such heaters are small,
they must operate at a high surface watt density and
consequently high temperature.

Answer / ash

When a motor is built as a "totally enclosed" (TE) unit, no free interchange of air can take place between interior and exterior. That's good protection against entry of solid or liquid contaminants.

But no enclosure can be airtight. As the TE motor heats and cools between "on" and "off," or from day to night, outside air will "breathe", in and out, and the water vapor in that air will condense on interior surfaces of winding and bearings. The result will eventually be insulation failure and bearing corrosion.

To prevent that, the motor's interior needs to be kept warm — above the condensation temperature — whenever it's not running. This is particularly true for motors that run only a few hours a day, are seasonally idle, or are installed in unusually damp locations. It's not a function of motor size or type. The same conditions exist, and will be equally damaging, whether the motor is 1 horsepower or 1000.

Answer / k.prakashchandra

It is used to warm up inside of panel or motor .In case of
motor,now instead of flat space heater ,current is passed
through winding using a transformer

What do you mean by turns ratio of instrument transformer?

0 Answers  

---

in transformer star connection with neutral are shorted. is there is any effect.

1 Answers  

---

A 12.5 hp slip ring motor taking high initial current and its MPCB is getting open.what may be the reason?

3 Answers  

---

what is the function of short circuit maintenance ct and droop ct.

1 Answers   L&T,

---

what percentage of marks in B-TECH is needed for section engineering exam

1 Answers   RRB,

---

---

3 ph motor connected in star delta starter. when we start the motor it run in star but when in is going in delta it trips the main incoming supply. why?

3 Answers   Bajaj Hindusthan,

---

can we use generator(a.c) as a motor.if so how if not why.

2 Answers  

---

1 Ton = ? amperes & power. How much power 1.5 TON split AC consumes in an hour at 17 C , 26 C & 28 C (thermostat' temperature).

18 Answers   Aamal, Ashiana Housing, Carrier, College School Exams Tests, Eastin Hotels, Godrej, LG, Medha, Medha Servo, Onida, Orean, PEL, Sahara, Voltas,

---

What Is Transformer Impedance ?

6 Answers   Con Edison,

---

how works inductive &capacitive sensors?

0 Answers  

---

why DC source is used to idetify the polarity of CT/PT?

1 Answers  

---

Whats the minimum value for I.R. that can be allowed for HT & LT alternators for operation?

1 Answers  

---