310 Voltage Regulator Location

Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
Make sure your AC aft end switch is off position.

paulj :hook2:
Paul, are you telling him to be sure the battery charger is turned off? All that would do is change the voltage being measured, and can be done from the electric panel at the nav station, maybe more easily. Regardless, when the ignition switch is turned off, there should be 0 volts at the panel meter.
 

paulj

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Mar 16, 2007
1,361
Catalina 310 Anacortes,Wa
What I am saying is when trouble shooting, I use the process of power in power out.
If the voltage is coming from another source this will eliminate one possibility for sure.
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
What I am saying is when trouble shooting, I use the process of power in power out.
If the voltage is coming from another source this will eliminate one possibility for sure.
I see. Still think his panel meter must be bad. Reading 12 V with the key switch off is the red flag. I’d open up the pod and measure the voltage directly with a meter that is known to work. It’s a pain to open and close, but he’ll need to do that to replace the meter eventually, so good practice. :)
 
Mar 16, 2018
32
Catalina 310 202 Carlyle, IL
Make sure your AC aft end switch is off position.

paulj :hook2:
The first picture is how the gauge reads key in our out, the second, key on, engine not running. What is your concern/point?

Thanks!
 

JRT

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Feb 14, 2017
2,037
Catalina 310 211 Lake Guntersville, AL
Have you actually checked the input volts at the wires that feed the gauge? I'd open that up and make very sure your gauge is not actually receiving 12 with key off, that would be something very goofy that the PO did. If the wires to the gauge are not sending any volts then you know you have a bad gauge, otherwise you have a bigger problem.
 
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paulj

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Mar 16, 2007
1,361
Catalina 310 Anacortes,Wa
My point is do not have the rear AC switch in the on position.... while the key is in or out, or switch on or off or engine running or not running. This not a normal operation condition.

paulj
 
Mar 16, 2018
32
Catalina 310 202 Carlyle, IL
Paulj,

Just to be clear, what are you referring to by the "rear AC" switch? Thanks.
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
My point is do not have the rear AC switch in the on position.... while the key is in or out, or switch on or off or engine running or not running. This not a normal operation condition.

paulj
Paulj, what’s the issue with leaving the AC turned on? How is it not a normal operation condition?
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
That is an internally regulated Korean made Mando alternator. It's an inexpensive knock-off of the Leece-Neville 8MR alternators that were originally used by Universal/Westerbeke and still are for their "optional" sizes...
Maine Sail, I’ve read your articles on alternators, but still have questions. Usage certainly matters, but in a case like this, what are the options for upgrading, given an FLA bank of 400 AH or so and mostly day sailing? Can this alternator be modified with your kit, producing an externally regulated system, with optional temperature sensors? Or would it make more sense to buy a new CMI 90/105 alternator? Or is the Mando ok in that situation?
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
Maine Sail, I’ve read your articles on alternators, but still have questions. Usage certainly matters, but in a case like this, what are the options for upgrading, given an FLA bank of 400 AH or so and mostly day sailing? Can this alternator be modified with your kit, producing an externally regulated system, with optional temperature sensors? Or would it make more sense to buy a new CMI 90/105 alternator? Or is the Mando ok in that situation?
Mando never made an ER kit and they are not real easy to convert to ER. Stack that on top of the fact that it's just a 55A unit that's only really capable of about 25-30A when hot, and that Mando no longer makes them, so you're now getting Chinese clones, and it winds up being a "keep it as a spare"...

There are a number of externally regulated options we offer including a new very affordable 2" foot 72A model (provided you have a 3/8" pivot bolt). The CMI-90-ER and CMI-105-ER are more flexible in terms of mounting but the 105-ER is the better deal for only $4.00 more..
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
Maine Sail, I’ve read your articles on alternators, but still have questions. Usage certainly matters, but in a case like this, what are the options for upgrading, given an FLA bank of 400 AH or so and mostly day sailing? Can this alternator be modified with your kit, producing an externally regulated system, with optional temperature sensors? Or would it make more sense to buy a new CMI 90/105 alternator? Or is the Mando ok in that situation?
I haven't written it up yet (way behind on all the upgrades) but I installed the CMI 105 with the Balmar MC614 and love the upgrade. We haven't been to a marina in 2-3 years? and live on the hook. We either charge from solar or the engine.
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
I haven't written it up yet (way behind on all the upgrades) but I installed the CMI 105 with the Balmar MC614 and love the upgrade. We haven't been to a marina in 2-3 years? and live on the hook. We either charge from solar or the engine.
I’m not surprised you’re happy with that upgrade. For our usage it’s maybe overkill. I do wonder if temperature sensing (batteries and/or alternator) would be worthwhile for us? Once you add external regulation and both temp sensors the difference in price between the 72A and 105A versions isn’t that much.
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
I’m not surprised you’re happy with that upgrade. For our usage it’s maybe overkill. I do wonder if temperature sensing (batteries and/or alternator) would be worthwhile for us? Once you add external regulation and both temp sensors the difference in price between the 72A and 105A versions isn’t that much.
Yes I believe it would be. We live on our solar most of the time. But those days we would start traveling early took a toll on our alternators. We had been through 6 in the past 4 years with the same bank as you. Typically the problems would arise from motor on cloudy days or during night passages. The alternator would heat up and fry trying to fill the deep cycle bank. The temp sensors and the belt manager function of the external regulator were the most important features for me.
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
But those days we would start traveling early took a toll on our alternators. We had been through 6 in the past 4 years with the same bank as you. Typically the problems would arise from motor on cloudy days or during night passages. The alternator would heat up and fry trying to fill the deep cycle bank. The temp sensors and the belt manager function of the external regulator were the most important features for me.
Bingo! Your results are not at all uncommon for a cruiser.

The stock Leece-Neville or Mando factory alternators were never intended to charge large deeply discharged banks for hours at full output. If you shallow cycle ( = short bulk duration), and have poor volt-sensing (most stock alternators), they can often survive. The best method, to protect a small-frame alternator, is to over-size in amperage then current limit it using Belt Load Manager and an alternator temp sensor.
 
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Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
Bingo! Your results are not at all uncommon for a cruiser.

The stock Leece-Neville or Mando factory alternators were never intended to charge large deeply discharged banks for hours at full output. If you shallow cycle ( = short bulk duration), and have poor volt-sensing (most stock alternators), they can often survive. The best method, to protect a small-frame alternator, is to over-size in amperage then current limit it using Belt Load Manager and an alternator temp sensor.
Maine Sail, what’s the difference between the ARS-5H and MC-614H? In particular when being used for shallow cycle charging most of the time. Thanks!
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
Maine Sail, what’s the difference between the ARS-5H and MC-614H? In particular when being used for shallow cycle charging most of the time. Thanks!
MC-614H has two battery temp sensor ports, can drive more field current so it runs a bit cooler (two output FET's vs. one), has a dedicated voltage sense lead and some minor programming tweaks. The ARS-5H will do almost everything the MC-614H can do...
 
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Nov 18, 2010
2,441
Catalina 310 Hingham, MA
MC-614H has two battery temp sensor ports, can drive more field current so it runs a bit cooler (two output FET's vs. one), has a dedicated voltage sense lead and some minor programming tweaks. The ARS-5H will do almost everything the MC-614H can do...
And if you ever go to lithium ion batteries in the future then the volt sensing is important. Actually it's important for all battery types but critical for lithium.
 

JRT

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Feb 14, 2017
2,037
Catalina 310 211 Lake Guntersville, AL
@JK_Boston_Catalina310 what pushed you to go lithium ion? My system is relatively new, 2 year old ProNautic 12-40P, 4 6V Duracell Ultra Golf Cart Batteries, SLIGC110, 208 AH @ 20 hours and a separate 12V starting battery but still the stock alternator. Since we are just day sailing right now and spend a large amount of time on shore power, no solar either. The alternator is fine and works for us for now, but when it goes I'll probably look at options from MS.