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What's WRONG with my SHORE POWER CONNECTION ?? | Ask The Expert with NIGEL CALDER

January 11, 2025 · 4 min · 3K views

What this video covers

A 16-amp shore power breaker that trips after 20 minutes of operation indicates a thermal overload condition on the circuit.1:32 Because the breaker trips faster upon reset, the device is likely heating up under a load exceeding its capacity.1:38 A 16-amp breaker typically trips at approximately 130 percent of its rating, or 20 amps, which corresponds to a load of four to five kilowatts.2:25 The fact that the system functions normally on 32-amp connections suggests the boat’s internal AC loads, such as air conditioning units, exceed the 16-amp supply limit.2:07 The boat’s main AC breaker may be incorrectly sized at 32 amps, preventing it from tripping before the shore-side breaker.2:48 Replacing a galvanic isolator with an isolation transformer is a safe and effective upgrade, but it will not resolve this specific overload issue.1:04 Systematic testing by isolating individual AC loads remains the primary method for identifying the source of the excessive power draw.3:21

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