Look inside the DB box
See the bigger blocks with test button?
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For every water heater:
You need to have one big block with test button that:
a) cuts off ONLY the water heater when Test is pressed (NOT the whole house) AND
b) is rated at 10mA (0.01A).
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And why do you need this protection?
a) It's the law - https://www.st.gov.my/en/contents/publicati...r%20Systems.pdf
b) Funerals are expensive
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