Mystery switch

[dennis41]

Still getting acquainted with my C30CB. Discovered an unidentified red switch in port cockpit locker (the big one, part of the deck) connected to very thick red wires. I did not get a Cutwater orientation tour, so the function of this switch is a mystery to me. Any suggestions? Why this isn't identified in the so-called "owners manual" is beyond me. I do see a switch in the wiring schematic labeled "inverter switch". Could this be it? If so,....how/when to use it?

 

[Smcavana]

On our 2011 R27 Classic, there's a large red rotary switch that isolates the batteries from the inverter/charger. Could that be it?

 

[Matty]

I have a red inverter switch as well. You can test to see if that is it by -

turn power selector switch to inverter. Doing this only tells the system which power source you want. It does not turn on the inverter. plug something into outlet and see if it comes on. Unless you press and hold that switch for about 3 seconds the plug should not have inverter power. When inverter is on switch should light up red. Might hear a short beep. To turn it off press the switch again.

 

[Connerkip]

Make sure you keep that one on or your house batteries will not get charged, and will run down. It is the breaker which connects the house batteries to the inverter charger.

 

[Boatagain]

My guess is that your mystery is the rotary battery switch for the generator. It’s just like the larger ones in the forward compartment on the starboard side of the cockpit (just inside the shore power connectors): house, engine, thruster etc. Of course, this one controls battery power to the generator.

 

[Matty]

On most models there is a difference between inverter switch and battery charger breaker. Breaker needs to be on to charge batteries. Draws power to batteries. Inverter switch should only be on when you need inverter power ie not on shore or generator power and need ac power. Left on all the time may drain your house batteries quickly. Inverter draws power from batteries to change it from 12v to 110. In many cases it is the same unit that serves two purposes. Hence the reason for two switches.
So answer depends on which switch you are seeing. Inverter switch may be about one inch long and red. The power selector switches are much larger.

 

[SassyRed]

If you are referring to the switch I think you are, Connerkip has it right. This switch connects the combination charger/inverter to the batteries. In the user manual I have (pdf) the schematic is on page 34. The switch needs to be on for the charger to charge the batteries from shore power and it needs to be on when you disconnect from shore power and want to use the inverter to create 110 volt AC for the boat. The inverter is smart enough to do the right thing depending on whether it senses 110 coming in from shore power. I wouldn’t expect the inverter to draw much power from the batteries if you are off shore power but are not running anything that requires 110. I have never measured this, but I know others who have anchored often, and they have never mentioned any issue. We never turn ours off.

 

[dennis41]

Thanks everyone for your explanations. I shall leave the switch in the ON position. Have not used 110 power while underway/at anchor, but if we do, it will only be for lightweight items requiring very little juice. Wish Fluid Motion would publish a REAL operators manual.

 

[Connerkip]

By the way, on my C30, the generator start uses the engine start battery, if this helps map out your switches. So the engine battery switch, controls the feed from the engine battery to the generator.