What are the difference between C-Curve and D-Curve for
MCB's.
- 17 Answers
- 185626 Views
- ABB, DLF, Essar, GK companies, Nissi Engineering Solution, I also Faced
- E-Mail Answers
Answer Posted / simon
Awesome thread with a lot of almost correct and mostly
correct answers.
The challenge is knowing to which standard a particular
breaker was manufactured.
AS/NZS 4898 specifies:
B Curve between 3 In and 5 In
C Curve between 5 In and 10 In
D Curve between 10 In and 14 In
This was an update to AS 3947.2 which specified:
B Curve between 3.2 In and 4.8 In
C Curve between 7 In and 10 In
D Curve between 10 In and 14 In
The application notes in #11 and #13 are pretty much spot on.
Now lets assume we're only using AS/NZS 4898 breakers.
Lets assume we're using a Clipsal C60 10A B curve breaker.
The breaker should operate electromagnetically (<0.2s)with
an inrush current greater than 30A (3 x 10A).
The same 10A breaker however with 15A of current will not
trip electromagnetically but will trip thermally between 30
and 600 seconds after load is applied.
A C curve breaker of the same type should not operate
electromagnetically at either 15A or 30A. It should operate
thermally between 30 and 1000 seconds after a 15A load is
applied and between 6 and 50 seconds after a 30A load is
applied.
Note the distinct difference between and instantaneous /
electromagnetic trip and a delayed / thermal trip.
| Is This Answer Correct ? | 10 Yes | 4 No |
Post New Answer View All Answers
I completed my BE EEE degree 2006 .... which license should i apply .... ?????
advantage of motor design on higher power factor . normally motors are designed for .8 power factor. what is advantage of designing at .88 power factor
How npn and pnp transistor works
What do you mean by Stimulastion Test in Diesel Genarator / Why & when it's conducted ?
please explain to me how to calculate current,voltage,resistance with formula??
Two electric lamps 40 W, 220 V each are connected in series across 220 V. What is the power consumed by the connection?
what is the difference between c power and U power acb breaker
what is the series parallel connection of capacitors? and how can we use these application in three phase motors for controlling torque?
how calculate the electrical load for industry and office
how choose conductor&depending upon load
who can measure the size of power cable?
What are the application of filter?
Please tell me the earthing procedures adopted for the STAR-STAR 3 Phase transformer in india and give a better sugession for earthing
How to operate a ac chilar plant?
what will happens if one phase is missing for 33/11kv power transfomer and why?
