WE are using a 63A MCCB(SIEMENS MAKE) for one of the feeder
in LV substation panel.It is supplying to a lighting & power
socket DB.Settings in the MCCB is Ir = 63 * 1 , Isd = 8
times of Ir , tsd = 0.5 sec( I2 t off).
Sometimes this MCCB is tripping .But no trip in DB MCB.
Can anybody tell me reason ?
From where i can know about the MCCB settings?
Answers were Sorted based on User's Feedback
Answer / ranveer
Dear fren i think your Isd is very much high or it may
highest in. kindly che it out and may consult your vendor
Is This Answer Correct ? | 4 Yes | 1 No |
Answer / abdul
HI Friend,
I think there must be a earth leakage in your receiving end.
Always the MCB trips for Short circit,where as the MCCB
trips for both earth leakage & short circuit.
Is This Answer Correct ? | 1 Yes | 1 No |
Answer / kyle
Hi,
Is it instantaneous tripping? If it is, Isd might be too low
(in fact it is consider high in this case) and tsd might be
too short, need to check the downstream loads.
might to provide more info?
Is This Answer Correct ? | 0 Yes | 0 No |
This may be due to absense of discrimination feature in
DB.or cascading is not as per requirement.better to have a
word with siemens engineer
Is This Answer Correct ? | 1 Yes | 3 No |
what is cathodic protection in Tank,and product pipelines?
what is ground clearence ,what is minimum ground clearence ,i.e present value following in india ,is it changes wit conductor size ,kva rating.surface
for same rating of a transformer and induction motor which one will have higher magnetising current flowing?
What is the funstion of buscoplure in LT panel? which propouse using the buscoplre
What is the formula to calculate distribution transformer De-rating on iron losses basis
How does a digital electronic meter work??????
what is GRR(Grid Rotot resistance)?Why it is used beside of LRS?
9 Answers ACC, L&T, Sri Biotech,
If MF is 30000, pt ratio is 110 kV/110 v then what is the ct ratio?
What type of tranformer generaly at soft wares like capacity 2000 kva 1800 kva etc iam confused it CT or PT OR distribution tranformer
dear sir, i completed diploma in electrical in 2005, how i can get electrical supervisor liance in mumbai
how does an centrifugal and screw type chiller will work. which chiller efficiency is high and why.
What is the direction of rotation of blades in a table fan and in a ceiling fan ?