Interested to Buy Any Domain ? << Click Here >> for more details...
why circuit breaker closing time is always higher then
tripping / opening time.
- 13 Answers
- 47914 Views
- United Phosphorus, I also Faced
- E-Mail Answers
Answer Posted / michael von zechlin
Neither of you are correct and for that matter who really
cares which is greater?
The opening and closing times of circuit breakers are
based on mechanical variables such as charging spring
tension, contact gap, trip mechanism delay etc. The goal
for a circuit breaker is to make or break the contacts as
quickly as possible to either slam the device on line or
open the contacts quickly enough to minimize the time that
an arc exists at the contacts.
What is significant are two measurements that provide an
indication of what the actual operating characteristics of
the circuit breaker are.
First, connect the contacts in series with one another
and a timer such that the circuit goes timer, 1st contact
set, 2nd contact set, 3rd contact set timer. (In one out
the other). Time the opening and closing of the circuit
breaker contacts. This will provide the fastest set of
contact make/break time.
Second, connect the contacts so that they are in
parallel with eachother record the value (This is the
average open/close time).
Once you have done this several times, say about 20,
take an average of each of the first/second measurement
times. Each manufacturer of circuit breakers has published
values for what those readings should be (average.
The significant readings of circuit breaker testing are
not usually related to the timing of the contacts, yes the
contacts can cause a motor to briefly single phase for less
than maybe 2 complete power cycles but not enough to really
matter, the significant measurements are those of mico-ohm
or millivolt drop across the contacts and closing spring
tension.
| Is This Answer Correct ? | 12 Yes | 2 No |
Post New Answer View All Answers
Why it need to form a capcitor when it not been in use from three or two year. Plz describe it technically.
The efficiency of a 100kva transformer is 0.98 at full load as well as half load , for this transformer what is the Copper loss at full load ?
What are the uses of stepper motor?
WHAT ARE THE CHARACTERISTICS OF AN VOLTAG AMPLIFIER
What is the actual meaning of thermal power efficiency ?
HOW DO YOU CAN CHECK A 15KV DIODE, WHETHER IT IS OK OR NOT?
How would you calculate power loss in a resistor?
how to select automotive wire by mathematical equation with given current, vlotage and resistance
Why we are going for converter transformers for DC drives application instead of distribution transformer?
Can u Explain about the electronic trivector meter and the use of data converters in them?
advantages & disadvantages of Lagging and leading power factor .
What is NGR . What is the purpose of 10 sec ,60 sec rating of NGR.
how to test and calculat the head and discharge in borewell compressor
Where is the best place to mount distribution panel in a house.
What is the maximum number of swithes that can be connected in series up to down stream point in an LV Distribution system?
