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circuit-breaker allegedly "getting more sensitive"

Former Community Member
Former Community Member
OK, usual caravan park issues with more pitches than incoming supply, so client has acknowledged this by installing 10 A circuit-breakers for each 16 A outlet. With 24 pitches on a presumed 80 A single-phase cut-out, he has got away with it..... so far, but he doesn't close for winter....


He has a few regulars that complain about the 10 A circuit-breaker being too sensitive so client believes them and has fitted new 10 A circuit-breakers ready for this weekend.


Considering that a 10 A circuit-breaker will run at 11.3 A continuously and 16 A for about 10 minutes, I'm more inclined to think that the "shed puller's" use of the 2 kW built in heater, 2 kW supplementary fan heater, fridge and domestic 3 kW kettle plus entertainment equipment are more likely....


But, has anyone carried out any tests on circuit-breakers to prove/disprove the alleged reduced rating? Or links to any such reports?


Regards


BOD
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  • 0
    perspicacious:

    Hmm, so a EICR carried out on my dwelling with a 16 A circuit-breaker on my 3 kW immersion heater in a 210 litre cylinder would result in what code? Assuming naturally that the rest of my dwelling electrics are perfect.................................




    Just how big is your bath BOD?


    Assume incoming water temperature is 10 deg C and you want 80 litres at 40 deg C.


    It takes 1 calorie = 4.2 J to heat 1 cc of water by 1 deg C

    4.2 x 30 = 126 J to heat 1 cc by 30 deg C

    = 126 W for 1 sec

    80 l = 80,000 cc so we need 126 x 80,000 W for 1 sec

    a 3 kW immersion will take 126 x 80,000 ÷ 3,000 sec

    = 126 x 80 ÷ 3 = 3360 sec or 56 minutes.


Reply
  • 0
    perspicacious:

    Hmm, so a EICR carried out on my dwelling with a 16 A circuit-breaker on my 3 kW immersion heater in a 210 litre cylinder would result in what code? Assuming naturally that the rest of my dwelling electrics are perfect.................................




    Just how big is your bath BOD?


    Assume incoming water temperature is 10 deg C and you want 80 litres at 40 deg C.


    It takes 1 calorie = 4.2 J to heat 1 cc of water by 1 deg C

    4.2 x 30 = 126 J to heat 1 cc by 30 deg C

    = 126 W for 1 sec

    80 l = 80,000 cc so we need 126 x 80,000 W for 1 sec

    a 3 kW immersion will take 126 x 80,000 ÷ 3,000 sec

    = 126 x 80 ÷ 3 = 3360 sec or 56 minutes.


Children
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