Answer / jesudoss

can ..u can use electrical interlock acb between mccb.ACB
should have NO,NC contacts.now new MCCBs also have NO,NC
contacts(ex:ABB TMAX - this MCCB have
charging,closing,opening coils also).

Answer / g.pattabiraman

For positive, fail safe interlocking, between ACB and MCCB to prevent both getting ON at any given time,
use of UNDER VOLTAGE COIL, along with auxiliary switches of the breakers is needed

ACB under voltage coil in series with MCCB aux. N.C contact
and MCCB under volt coil in series with ACB aux. N.C contact will give this fail safe protection

Motor operation or manual operation are user choice

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