[Crown Royal]

On C-Charles external regulator I’m getting a fault code of can’t start the field on my port side. Both voltage gauges show 13.7 V when running. I’m not good with electrical can anybody tell me what that means and what to do about it.
Thanks 
Chuck

[jclark003]

The regulator reads battery voltage and controls the alternator excitation by increasing or decreasing the field voltage. So the field wire is the regulator output signal that tells the alternator to increase or decrease voltage back to the battery.

I would test again however first make sure your batteries are not tied together (closed emergency interconnect switch) and that the battery charger and generator are not running. Check your battery bank voltage with both engines off, then start your port engine and check voltage again on whatever bank that alternator is connected to. You should see a rise from 12.2 or so volts to up around 14. If you don’t get proper charge voltage you probably have a bad regulator or alternator. To determine which you would need to check field voltage at alternator with engine running. No field voltage usually means regulator is bad or a wiring issue. Good luck

[Crown Royal]

Thanks for the info, everything seems to be tied together both gauges come on when either switch is turned on and when either engine is run they both show the same charge rate. I will try to confirm the emergency switch is not connecting and test alt.output. My schematic is not correct as it shows a different charge system so no help there and being in Mexico tough to find knowledgeable service techs.
Thanks

[jclark003]

Make sure your battery charger is off or you will show the same charge voltage on both banks. It’s helpful to use a digital volt meter, checking voltage at alternator battery terminal with both engines off and again with just port engine running. This will tell you if alternator is charging. If you do see charge voltage, leaving the port engine running put the meter on the other alternator battery post and see if the same voltage is present. If so batteries could be tied together.

[Crown Royal]

Thanks jclark, today I checked as recommended charger and both engines off , at the alternator + post port read 12.6V starboard read 13V with dmm started port read with engine @ 1200 rpm it read 12.5V read starboard with just port still running read 13V so then shut engine down took a jumper wire and disconnected the field wire on port engine hooked jumper from field terminal to alternator + terminal and started port engine dmm read 14.4 V
So shows alternator good regulator possible problem fault light on regulator reads can’t turn field on. I will start checking regulator wiring any other suggestions welcomed.
Thanks for your help.

[jclark003]

Doesn’t sound promising for the regulator. I would first cycle the power to the regulator. There should be a breaker or if not, open both batter disconnect switches. The lights on the front panel should all be extinguished. Power it back up then check field voltage at the regulator and at the alternator with key on. I’m guessing you should see around 9 volts (you can check the other side).

My Tiara has a separate breaker for the alternator field. If you don’t have a breaker there may be a fuse somewhere that is not allowing current to alternator. A separate wire from the regulator to the alt field will also work as a test. Just be careful if it is not fused.

[Crown Royal]

I cycled the regulators and checked the voltage from regulator field and at the alternator nothing from the port reg but 12.4 from the starboard reg. all other terminals check out except for the field on the port. on the starboard all checks out as shown on the charles reg manual. My question is can I change just the port regulator say to a balmar and not have an issue with the system?

Thanks for all the help !

[jclark003]

Yes I believe so. If I remember correctly the Charles regulator should be 2 separate circuit boards, one for each alternator/battery bank that operate independently. So your options are to replace the entire assembly with a dual bank/alternator regulator or install a separate single regulator to work along side the Charles.

[Crown Royal]

Yes I believe so. If I remember correctly the Charles regulator should be 2 separate circuit boards, one for each alternator/battery bank that operate independently. So your options are to replace the entire assembly with a dual bank/alternator regulator or install a separate single regulator to work along side the Charles.

I have decided to go with the Balmar MC-618 it sounds pretty simple to set up and will be easy to add another one if the starboard fails. Thanks for all the help and recommendations it's appreciated.

Chuck

[jclark003]

Good choice and good luck