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Regulator set point

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echristley(at)att.net
Guest

Posted: Mon Mar 19, 2018 5:41 pm Post subject: Regulator set point

I've switched to using a LiFePO battery.  I accept the limited power reserve it has in the case of a generator issue, because I'm not a big fan of really long flight legs  and the weight benefit for my Corvair equipped 601XL is exceptional.  That being said, more reserve is a good thing.  My Kubota regulator for the PM generator is set at 13.8V.  There was some talk a few years ago of modifying the regulator to a higher set point.  How would this feat be accomplished?  I'd like to set it between 14.3 and 14.5.

user9253

Joined: 28 Mar 2008
Posts: 1925
Location: Riley TWP Michigan

Posted: Mon Mar 19, 2018 9:41 pm Post subject: Re: Regulator set point

The easy way is to replace the regulator.  Search eBay for part number AM101406.  I think that the only difference between the search results is the price.

_________________
Joe Gores

echristley(at)att.net
Guest

Posted: Tue Mar 20, 2018 7:43 am Post subject: Regulator set point

Thanks Joe, but how are you able to tell that these regulators have a higher set point?



 

    On Tuesday, March 20, 2018 1:43 AM, user9253 <fransew(at)gmail.com> wrote:



  



 --> AeroElectric-List message posted by: "user9253" <fransew(at)gmail.com (fransew(at)gmail.com)>



The easy way is to replace the regulator.  Search eBay for part number AM101406.  I think that the only difference between the search results is the price.



--------



Joe Gores



Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=478752#478752



http://www.matron===================



http://wiki.matronic=======================

</;                     &nb -->

user9253

Joined: 28 Mar 2008
Posts: 1925
Location: Riley TWP Michigan

Posted: Tue Mar 20, 2018 8:54 am Post subject: Re: Regulator set point

I have a John Deere regulator in my RV-12.  The system voltage is now a half volt higher than when using the Ducati regulator.  Not saying the regulator that you buy will have a higher voltage, but for $25 it is worth a try.  The Ducati regulators fail so often that some pilots carry a spare.  The important thing is to mount them with heat conductive paste to help carry the heat away.  Heat is the enemy of electronics.

_________________
Joe Gores

yellowduckduo(at)gmail.co
Guest

Posted: Tue Mar 20, 2018 9:00 am Post subject: Regulator set point

I've had two of those PM rectifier regulators consistently put out 14.4 

volts (+/- 0.1)

Mine were purchased directly from John Deere although I doubt that 

matters other than doubling or tripling the price.

Ken



On 20/03/2018 11:42 AM, Ernest Christlike wrote:

 	  Quote: 	
		   Thanks Joe, but how are you able to tell that these regulators have a 

 higher set point?





 On Tuesday, March 20, 2018 1:43 AM, user9253 <fransew(at)gmail.com> wrote:

 

 <mailto:fransew(at)gmail.com>>



 The easy way is to replace the regulator.  Search eBay for part number 

 AM101406.  I think that the only difference between the search results 

 is the price.



 --------

 Joe Gores





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=478752#478752



 http://www.matron===================

 http://wiki.matronic=======================

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Mar 20, 2018 4:28 pm Post subject: Regulator set point

At 08:40 PM 3/19/2018, you wrote:

  	  Quote: 	
		  I've switched to using a LiFePO battery.  I accept the limited power reserve it has in the case of a generator issue, because I'm not a big fan of really long flight legs  and the weight benefit for my Corvair equipped 601XL is exceptional.  That being said, more reserve is a good thing.  My Kubota regulator for the PM generator is set at 13.8V.  There was some talk a few years ago of modifying the regulator to a higher set point.  How would this feat be accomplished?  I'd like to set it between 14.3 and 14.5.



 	


  If it's a potted assembly, like many small pm rectifier/

  regulators are, then adjusting the setpoint is not practical

  and pretty much impossible. If it can be disassembled and

  the parts are accessible, it MAY be possible to make

  some adjustment to the voltage control circuits.



  Actually, you might consider leaving it at 13.8 . . . if

  indeed it really runs at that value or a tad higher.

  See https://goo.gl/vCd59M 



  Note that the LiFePO4 cells will achieve 100% charge

  or very close to it with a charging level of 3.4v per

  cell (13.6 volts on the bus). But as the experiment

  shows, there is a tipping point at about 3.3 volts

  per cell that severely limits energy replacement

  in the LiFePO4 cells. So if you're running 13.8, you

  can probably leave it alone.



 

 

   Bob . . .

echristley(at)att.net
Guest

Posted: Wed Mar 21, 2018 6:39 am Post subject: Regulator set point

That's some powerful information, Bob.  



I'm not in a position to experiment on this point, but these tests would indicate that a lead-acid and LiiFePO battery could live together.  The CG challenged builder could put a small (less than $100) LiFePO on the firewall to get cranking amps, and then locate an AGM in the tail for endurance loads.  With the necessity to carry cranking loads removed, a 14 to 16 AWG wire could replace the 00 AWG starter cable running the entire length of the airframe.

Mixing battery chemistries is generally discouraged for good reason, but this mix could be beneficial to a lot of builders.

 

    On Tuesday, March 20, 2018 8:29 PM, "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com> wrote:



  



  At 08:40 PM 3/19/2018, you wrote:  	  Quote: 	
		  I've switched to using a LiFePO battery.  I accept the limited power reserve it has in the case of a generator issue, because I'm not a big fan of really long flight legs  and the weight benefit for my Corvair equipped 601XL is exceptional.  That being said, more reserve is a good thing.  My Kubota regulator for the PM generator is set at 13.8V.  There was some talk a few years ago of modifying the regulator to a higher set point.  How would this feat be accomplished?  I'd like to set it between 14.3 and 14.5. 	


  If it's a potted assembly, like many small pm rectifier/  regulators are, then adjusting the setpoint is not practical  and pretty much impossible. If it can be disassembled and  the parts are accessible, it MAY be possible to make  some adjustment to the voltage control circuits.  Actually, you might consider leaving it at 13.8 . . . if  indeed it really runs at that value or a tad higher.  See https://goo.gl/vCd59M   Note that the LiFePO4 cells will achieve 100% charge  or very close to it with a charging level of 3.4v per  cell (13.6 volts on the bus). But as the experiment  shows, there is a tipping point at about 3.3 volts  per cell that severely limits energy replacement  in the LiFePO4 cells. So if you're running 13.8, you  can probably leave it alone.  

    Bob . . .

ceengland7(at)gmail.com
Guest

Posted: Wed Mar 21, 2018 7:07 am Post subject: Regulator set point

Don't forget that the wire still must       carry both charge and discharge currents. A long run of even #14       could have significant voltage drop on a 12V system.

       

       On 3/21/2018 9:38 AM, Ernest Christley wrote:

     

      	  Quote: 	
		                  That's some           powerful information, Bob.Â  

         

         

         

         I'm not in a           position to experiment on this point, but these tests would           indicate that a lead-acid and LiiFePO battery could live           together.Â  The CG challenged builder could put a small (less           than $100) LiFePO on the firewall to get cranking amps, and           then locate an AGM in the tail for endurance loads.Â  With the           necessity to carry cranking loads removed, a 14 to 16 AWG wire           could replace the 00 AWG starter cable running the entire           length of the airframe.

         

           

         Mixing battery             chemistries is generally discouraged for good reason, but             this mix could be beneficial to a lot of builders.

         

           

         

                                                 On Tuesday,                   March 20, 2018 8:29 PM, "Robert L. Nuckolls, III"                   <nuckolls.bob(at)aeroelectric.com> (nuckolls.bob(at)aeroelectric.com) wrote:

                 

               

               

                                                                        At 08:40 PM 3/19/2018, you wrote:                                                                  	  Quote: 	
		  I've switched to using a LiFePO                         battery.Â  I accept the limited power reserve it                         has in the case of a                         generator issue, because I'm not a big fan of                         really long flight                         legsÂ  and the weight benefit for my Corvair                         equipped 601XL is                         exceptional.Â  That being said, more reserve is a                         good thing.Â                          My Kubota regulator for the PM generator is set                         at 13.8V.Â  There was                         some talk a few years ago of modifying the                         regulator to a higher set                         point.Â  How would this feat be accomplished?Â                          I'd like to set                         it between 14.3 and 14.5.                                                	
                     

                                          Â If it's a potted assembly, like many small pm                     rectifier/                     Â regulators are, then adjusting the setpoint is not                     practical                     Â and pretty much impossible. If it can be                     disassembled and                     Â the parts are accessible, it MAY be possible to                     make                     Â some adjustment to the voltage control circuits.                                          Â Actually, you might consider leaving it at 13.8 . .                     . if                     Â indeed it really runs at that value or a tad                     higher.                     Â See                     https://goo.gl/vCd59M                                                               Â Note that the LiFePO4 cells will achieve 100%                     charge                     Â or very close to it with a charging level of 3.4v                     per                     Â cell (13.6 volts on the bus). But as the experiment                     Â shows, there is a tipping point at about 3.3 volts                     Â per cell that severely limits energy replacement                     Â in the LiFePO4 cells. So if you're running 13.8,                     you                     Â can probably leave it alone.                                                               Â  Bob . . .                   

                 

                 

                 

               

             

           

         

       

     	
     

     	          		Virus-free. www.avast.com 		 	 [url=#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2] [/url]

nuckolls.bob(at)aeroelect
Guest

Posted: Wed Mar 21, 2018 8:08 am Post subject: Regulator set point

At 09:38 AM 3/21/2018, you wrote:

  	  Quote: 	
		  That's some powerful information, Bob.  



 I'm not in a position to experiment on this point,

 but these tests would indicate that a lead-acid and

 LiiFePO battery could live together. 	


   Sure . . . this has always been the case

   in terms of normal performance. I.e.

   crank the engine, support all loads with

   an altenrator including recharge of the

   battery and then shut down leaving all

   batteries fully charged.



   A 14.2 volt set-point has been the touchstone

   for operating lead-acid batteries since day-one,

   that same voltage is quite acceptable for

   LiFePO4.



   Lithium products that do no contain smart

   battery management systems are vulnerable

   to individual cell damage due to unbalanced

   recharging and cell destruction if discharged

   below some tipping point . . . generally pegged

   at 2.8 volts per cell (11.2v bus). The lead-acid

   battery will continue to deliver useful energy

   below this value . . . but not for long.



   Assuming that you limit endurance discharging

   of the 'barefooted' lithium battery to 11.2

   then you can essentially tap ALL chemical energy

   on board without risking damage to the lithium

   product.  But then, if the alternator is TU

   and you're boring holes in a very dark sky over

   unfriendly terrain, then the health and well-being

   of your lithium battery is, perhaps, of little

   concern.



  	  Quote: 	
		    The CG challenged builder could put a small (less than $100) LiFePO on the firewall to get cranking amps, and then locate an AGM in the tail for endurance loads.  With the necessity to carry cranking loads removed, a 14 to 16 AWG wire could replace the 00 AWG starter cable running the entire length of the airframe. 	


   Nobody needs 00AWG wire in a light plane

   for any reason EXCEPT comoposit seaplanes with big

   batteries in the nose for weight/balance

   concerns and engines high and aft on pylons.



   Everybody else is in good shape with 2AWG

   cranking feeders. For the scenario you propose,

   I wouldn't drop the rear battery feeder lower

   than 10AWG and I would protect that feeder

   with a fat maxifuse on the order of 60A.

   Wiring up front for all other cranking circuits

   could be 4 or even 6AWG.



   The fact that the lithium product is up front

   on short a short leash of fat wires insures

   lower voltage drops under normal charge/discharge

   cycles making your 13.8v set-point less

   problematic.  It's worth a try.



 

  	  Quote: 	
		  Mixing battery chemistries is generally discouraged for good reason, but this mix could be beneficial to a lot of builders. 	


   Every chemistry has it's own 'happy-space'

   boundaries where maximized performance

   can be exploited. Mixed chemistries can

   offer considerable overlap of happy-space

   where reliable operation can be achieved

   but with tighter boundaries. Lithium

   products with agile BMS can be intermixed

   with lead-acid with relative impunity.



 

 

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Wed Mar 21, 2018 8:11 am Post subject: Regulator set point

At 10:07 AM 3/21/2018, you wrote:

  	  Quote: 	
		  Don't forget that the wire still must carry both charge and discharge currents. A long run of even #14 could have significant voltage drop on a 12V system. 	


   Bingo. Give the man a Kewpie Doll!



 

   Bob . . .

jan_de_jong(at)casema.nl
Guest

Posted: Wed Mar 21, 2018 8:23 am Post subject: Regulator set point

I would like to mention: check any danger of high currents if a LiFePO4 

battery (13.2V) is directly parallelled with a lead-acid battery (12.6V).

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Mar 22, 2018 2:41 pm Post subject: Regulator set point

At 11:23 AM 3/21/2018, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: Jan de Jong <jan_de_jong(at)casema.nl>



 I would like to mention: check any danger of high currents if a LiFePO4 battery (13.2V) is directly parallelled with a lead-acid battery (12.6V). 	


   I just measured an SVLA resting voltage of 13.1 volts

   while my EarthX is 13.4 volts. When connected together,

   there WAS a circulating current on the order of 400mA.



   In an operational scenario where both batteries are

   floated on a 13.8 to 14.2 volts bus, I suspect

   the circulating currents between the two will be

   small in the event of alternator failure. If one

   sets 2.8v per cell as minimum discharge voltage, this

   translates to 11.2 volts which corresponds to a 90%

   plus depletion of the SVLVA as well.



 

   Bob . . .

jan_de_jong(at)casema.nl
Guest

Posted: Thu Mar 22, 2018 3:08 pm Post subject: Regulator set point

There might only be a concern then if an architecture allowed       parallelling after serious discharge of the lead-acid battery?     

Jan de Jong

          On 3/22/2018 11:40 PM, Robert L. Nuckolls, III wrote:

      	  Quote: 	
		         At 11:23 AM 3/21/2018, you wrote:

               	  Quote: 	
		  -->           AeroElectric-List message           posted by: Jan de Jong <jan_de_jong(at)casema.nl> (jan_de_jong(at)casema.nl)

           

           I would like to mention: check any danger of high currents if           a LiFePO4           battery (13.2V) is directly parallelled with a lead-acid           battery           (12.6V). 	
       

         I just measured an SVLA resting voltage of 13.1 volts

         while my EarthX is 13.4 volts. When connected together,

         there WAS a circulating current on the order of 400mA.

       

         In an operational scenario where both batteries are

         floated on a 13.8 to 14.2 volts bus, I suspect

         the circulating currents between the two will be

         small in the event of alternator failure. If one

         sets 2.8v per cell as minimum discharge voltage, this

         translates to 11.2 volts which corresponds to a 90%

         plus depletion of the SVLVA as well.

       

                

             Bob . . .

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