EMB120 FLC STOPPED CLB PRIOR TO REACHING ASSIGNED ALT TO AVOID TFC CONFLICT.

Narrative

THE FO OBTAINED THE CLRNC AND THE INITIAL ALT ASSIGNED WAS 9000 FT ON THE SEATTLE 2 DEP. AFTER LIFTOFF; THE TWR INSTRUCTED US TO FLY A HDG OF 130 DEGS AND CHANGE TO DEP CTL. WE CHKED IN WITH THE DEP CTLR AND STATED OUR ALT AND CLB LIMITS. THE CTLR WAS VERY BUSY AND RESPONDED ONLY WITH 'RADAR CONTACT' AND CONTINUED WORKING A JET THAT DEPARTED AHEAD OF US. AS WE CONTINUED OUR CLB; I COULD SEE ON THE TCASII THAT OUR FLT PATH WAS GOING TO CONFLICT WITH IFR TFC THAT WAS CLBING OFF A NEARBY SATELLITE ARPT FROM BEHIND AND TO OUR L. I LOCATED THE ACFT VISUALLY AND STOPPED OUR CLB JUST AS A TCASII ALERT WAS SOUNDED. THE CTLR FINALLY RECOGNIZED THE PROB AND INSTRUCTED US TO MAINTAIN VISUAL WITH THE ACFT AND MAINTAIN 5000 FT. AFTER THE TFC CONFLICT; THE FLT CONTINUED NORMALLY. UPON REACHING MY DEST; I CONTACTED THE ATC FACILITY BY TELEPHONE AND DISCUSSED THE SIT. I WAS TOLD BY THE SUPVR THAT CLRNC DELIVERY INCORRECTLY ASSIGNED OUR 9000 FT CLB LIMIT. THE DEP CTLR SHOULD HAVE ALSO CAUGHT THE ERROR ON THE CHK-IN; BUT WAS TOO BUSY AT THE TIME. WITHOUT THE TCASII SYS; I WOULD NOT HAVE BEEN AWARE OF THE TFC UNTIL A NEAR MISS WOULD HAVE OCCURRED.