Answer / ravi

Duty Cycle:-

In telecommunications and electronics, the duty
cycle is the fraction of time that a system is in
an "active" state. In particular, it is used in the
following contexts:

Duty cycle is the proportion of time during which a
component, device, or system is operated.[1] Suppose a disk
drive operates for 1 second, and is shut off for 99
seconds, then is run for 1 second again, and so on. The
drive runs for one out of 100 seconds, or 1/100 of the
time, and its duty cycle is therefore 1/100, or 1 percent.



Protection Class is for what?????????Fire,A/C's.....

Answer / er. vasim

Duty Cycle:- It is the classification based on time
duration for which a motor will be loaded
According to IsS 4722, following classes are assigned
S1-Continous
S2-Short time duty
S3- Intermitent periodic duty
S4- Intermitent periodic duty with starting
S5- Intermitent periodic duty with starting and electric
breaking
S6- Continous duty intermitent periodic loading
S7- Continous duty with starting and electric breaking
S8- continous duty with periodic speed change

IP Protection:
It stands for Ingress protection, According to IS 4691 IP
is classified as:

In IP their are two numerals, ie:IP56
1st numeral: protection against ingress of solid particles
or human body parts,etc
2nd numeral: protection against penetration of liquid

for 1st numeral
IP 1: protection against solid of 50 mm dia or more
2: protection agianst solid of 12.5 mm dia or more
3: 2.5 mm dia or more
4: 1-2.5mm dia
5 and 6: protection against dust particle

for 2nd numeral
1: protection against vertical fall of liquid
2:protection against fall of liquid at an angle of 15 degree
3: 60 degree
4: 180 degree (ie: heavy rain fall)
5 and 6:protection provided against liquid jet (very heavy
rush of liquid)
7 & 8:protection provided against total immersion in liquied

Answer / g.e.t.

Duty Cycle - The duty cycle of a machine refers to how long
it can keep operating before it needs a rest. If you're
referring to motors, then there are 8 duty cycles S1 to S8
(IEC Standard) depepnding on the duration of operation,
nature of operation (continuous or intermittent) and
ambient temperature.

Protection Class - It is generally specified in Ingress
Protection or "IP" standards. It tells us about how the
inside of a motor is protected from water and dust. "IP55"
is the most commonly used industrial standard cuz it
provides protection against dust particles and water sprays
from all directions.

Answer / ssreenu

He is asking about protection class like IP 65 etc.,

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