Interested to Buy Any Domain ? << Click Here >> for more details...
what is the difference between Ith & Iu rating in MCCB.
Particularly on SACE ABB Circuit Breaker?
- 2 Answers
- 18320 Views
- Siemens, I also Faced
- E-Mail Answers
Answer Posted / mazed
Extract form appendix K of standard IEC 60947 -2
Voltage
• Ue = Rated operational voltage
• Ui = Rated insulation voltage
• Uimp = Rated impulse withstand voltage
Current
• In = Rated current
• Ith = Conventional free –air thermal current
• Ithe = Conventional enclosed thermal current
Short -Circuit
• Icm = Rated short circuit making capacity
• Icu = Rated ultimate short circuit breaking capacity
• Ics = Rated service short circuit breaking capacity
• Icw = Rated short time withstand current
Trip unit
• Ir = Adjustable overload setting current
• 1.05xIr = Conventional non –tripping current
• 1.30xIr = Conventional tripping current
• Isd = Short time delay tripping setting current
• Ii = Instantaneous tripping setting current
| Is This Answer Correct ? | 8 Yes | 0 No |
Post New Answer View All Answers
Why colled 440V to 3-phase supply.
Bimetal strip used in overload relay what is that,which types of material used for that & percentage.
Define availability (operational)?
why occ characteristics curve in not tracing back when we are bringing back the rhoestat?
in HT service 3ph 4 wire service Y-phase voltage shows zero . whether it is meter fault? or what be the reason ? if y-ph voltage zero ,can current is recorded? reasons for failure?
hi frnds...pls send me aptransco previous papers .....pls..pls,,,(madhar.rocking@gmail.com)and suggest me some websites
For a stable system, where should the poles of a system be in a root loci plot?
why voltage form factor of PT are increase , when it is ecpected heigher spikes in system. how it is calculated.
i am completed diploma in ece,and working in ht and lt lines.so is elligible diploma in ece for get electrical C Licence?plse give ur opinion?
How to design pavement quality concrete by using C.R.C.P Method
how to select automotive wire by mathematical equation with given current, vlotage and resistance
What do you understand by oldham's coupling ?
how line turns ratio changes in 3 phase with change in connection
What is the difference between indoor and outdoor transformer
why swinburnes test cannot be performed on series machines?explain
