Examined dishwasher. Found customer using unit. Spoke with Henry from maintenance. Unit tripped main breaker 2 times on Thursday night and 2 times on Friday. Checked total amp draw on machine while in use. Each leg pulling 11-1/2 to 12 amps. Checked amp draw on conveyor motor okay. Maintenance checked draw on exhaust hood on roof okay. If problem persists may have possible weak breaker.