Tom
Administrator
- Joined
- Jan 13, 2005
- Posts
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FWIW we have two transfer switches on our boat:
Like Mark, I always turn off loads (and/or their respective breakers) before manually plugging in/connecting or removing shore, generator, or inverter power. I spent too many years replacing relays, switches and contactors (used for very large loads) due to arcing-induced damage. However, the transfer switch in the inverter is supposedly designed for hot switching, but I'm still gun shy and turn stuff off.
If you want to see arcing on switches due to opening under load, check out the ACBs (air circuit beakers) used for switching high voltage power lines and stepped-down voltage to substations. I've only seen them in use switching 132KV, and it's been many years since I worked around them, but they use a blast of compressed air to "blow away" the arc during switching.
edit: fixed typos.
- The transfer switch/relay in the inverter that automatically switches to inverter power when external (shore or generator) power is lost, and vice versa when external power is restored. Can also be activated manually.
- An interlocked pair of ganged double pole switches (4 total) used to manually switch between shore and generator power. The interlock physically prevents either pair of switches from being turned on while the other pair is on.
Like Mark, I always turn off loads (and/or their respective breakers) before manually plugging in/connecting or removing shore, generator, or inverter power. I spent too many years replacing relays, switches and contactors (used for very large loads) due to arcing-induced damage. However, the transfer switch in the inverter is supposedly designed for hot switching, but I'm still gun shy and turn stuff off.
If you want to see arcing on switches due to opening under load, check out the ACBs (air circuit beakers) used for switching high voltage power lines and stepped-down voltage to substations. I've only seen them in use switching 132KV, and it's been many years since I worked around them, but they use a blast of compressed air to "blow away" the arc during switching.
edit: fixed typos.