what is the function of NAT & NAC contacts in breaker
control switch (TNC)??
Answer Posted / rajesh t k
The NAT and NAC contacts are provided on TNC switch to facilitate additional functionalities from the TNC switch than mere Tripping or Closing.
These contacts are also known as Lost Motion Contacts. They help identify the last operation (Trip/Close) performed by the operator through the TNC switch.
The NAC contact will be closed whenever the operator turns the TNC lever to Close position and the contacts stays closed even after the lever is returned to the Neutral position by the operator, until the lever is turned to Trip side.
Hence, the 'Auto Trip' indication can be given via the NAC contact(instead of giving through an NO contact of the master trip relay), in series with the CB's 52b contact. That is, this is just an alternate way to wire up the 'Auto Trip' indication.
The NAT contact, likewise will be through whenever the CB has tripped via the TNC lever switch by the operator, until the lever is turned to Close position again.
Is This Answer Correct ? | 12 Yes | 0 No |
Post New Answer View All Answers
What are root loci?
What is the minimum value of hfe for the oscillations in transistorized rc phase shift oscillator?
What is the basic principal, by which DC voltage level is increased more than the supplied AC voltage during conversion. As upto AC level it is contorrled by firing anlge but after maximum level how is it possible.Please clear picture. OR we have to supply the higher level AC?
what is DRP panels?
Why the power generated in dams is complex power? Why the generators in dams cannot produce Real power directly (i.e power which has zero reactive part)?
what types of cable used in underground coal mining?
Whether 3 phase induction motorwith 100 hp capacity , Amp 160 for which sensitive earth fault relay , type CTUM 15 can be used?
how to select the isolation tranformer for siemens 802dsl cnotroller
How you calculating the 30 Hp 3 phase AC motor of power what size of cable is used for this motor?
Block diagram of Power line communication?
I WANT BHEL PREVIOUS QUESTION
132/6.6ππ πππππππππππ πππππππ πππ πππ πππππ πππ πππππππππ. πΈ'ππ πππππππ πππππππππππ ππ 6.6ππ/415π πππ πΈ πππππππ πππππππ ππ ππππ πππππ πππ ππ ππ 13/6.ππ πππππππππππ?? πΈπ π½π.. ππππ π ππ’??
We have studied about many techniques for finding the stability of system, ROOT LOCUS, ROUTH, BODE PLOT, POLER PLOT etc. In these which is used where. what are the difference among them... PLZ tell me.......
I Have 3 Phase 10 KW AC Alternator i found one phase weak, so what will be the reason & what action shouls i take to rectify the same.
In three pin plug 6 amp. 220V ac rating. Why earth pin diameter is higher than other two pin? What its purpose ?