A FLC; IN COORDINATION WITH THEIR MAINT; INCORRECTLY INTERPRETED THE PROCEDURE FOR DEFERRING A HEAT EXCHANGER COOLING FAN THAT HAD ONE OF ITS THREE CIRCUIT BREAKERS DAMAGED.

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UPON ARRIVING AT THE ACFT I DISCOVERED A CIRCUIT BREAKER ON THE LOWER PANEL BEHIND THE CAPT'S SEAT; WHICH APPEARED TO BE DAMAGED (BENT). I CALLED MAINT CTL AND ADVISE THEM OF WHAT I HAD FOUND. THE R HEAT EXCHANGER COOLING FAN CTL CIRCUIT BREAKER WAS DAMAGED. MAINT CTL SAID IF THE CIRCUIT BREAKER COULD BE PULLED WE COULD MEL THE HEAT EXCHANGER COOLING FAN. I PULLED THE CIRCUIT BREAKER; REVIEWED THE MEL; MADE A LOGBOOK ENTRY; AND ADVISED MAINT CTL. MAINT CTL WALKED ME THROUGH COMPLETING THE LOGBOOK ENTRIES; FILLING OUT THE MEL PLACARD; AND READ ME THE DISPATCH DEVIATION GUIDE MEL ITEM. AS WRITTEN. THE PROCEDURE SAYS: 'OPEN AND COLLAR AFFECTED (L OR R) HEAT EXCHANGER COOLING FAN CIRCUIT BREAKER.' SINCE I WAS DEALING WITH THE R HEAT EXCHANGER COOLING FAN CTR CIRCUIT BREAKER AND THE INSTRUCTIONS REFERRED TO '(L OR R) HEAT EXCHANGER COOLING FAN CIRCUIT BREAKER'; I MISINTERPRETED THE PROCEDURE. THE HEAT EXCHANGER COOLING FAN IS POWERED BY 3 PHASE AC AND HAS 3 CIRCUIT BREAKERS FOR EACH FAN. IF THE PROC HAD SAID '(L OR R) HEAT EXCHANGER COOLING FAN CIRCUIT BREAKERS'; I FEEL I WOULD HAVE BEEN LESS LIKELY TO MAKE THIS ERROR. THE DAMAGED CIRCUIT BREAKER COULD NOT BE COLLARED BECAUSE THERE WERE NO CIRCUIT BREAKER COLLARS ONBOARD THE ACFT (NORMALLY THERE IS A SUPPLY STORED WITH THE SPARE LIGHT BULBS). A MECHANIC AT OUR DESTINATION POINTED OUT MY ERROR WHEN I ADVISED HIM THAT WE NEEDED CIRCUIT BREAKER COLLARS ONBOARD AND THE DAMAGED CIRCUIT BREAKER NEEDED TO BE COLLARED.