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bobnoffs

Joined: 04 Jul 2012
Posts: 132
Location: northern wi.

Posted: Thu Oct 01, 2020 5:29 am Post subject: voltage monitor

hi all,

 i have earthx batteries and would like to install a voltage warning separate from my eis. the device must  activate below 13.5 volts . does anyone have any recommendations? i would think something is out there but i haven't seen it.

 thanks, bob noffs

ceengland7(at)gmail.com
Guest

Posted: Thu Oct 01, 2020 5:54 am Post subject: voltage monitor

On Thu, Oct 1, 2020 at 8:39 AM bobnoffs <icubob(at)gmail.com (icubob(at)gmail.com)> wrote:



 	  Quote: 	
		  --> AeroElectric-List message posted by: "bobnoffs" <icubob(at)gmail.com (icubob(at)gmail.com)>

 

 hi all,

 Â i have earthx batteries and would like to install a voltage warning separate from my eis. the device mustÂ  activate below 13.5 volts . does anyone have any recommendations? i would think something is out there but i haven't seen it.

 Â thanks, bob noffs

 	
Hi Bob,

A friend of mine has been using this for years, to alert him of alternator loss since he's using electronic ignition on his Lyc:

https://www.tomtop.com/p-e1021.htmlÂ 

It can be programmed to alert for both over and under-voltage and output fed to whatever you choose; light, buzzer, etc.

I bought a couple, but they're still sitting in my 'toy box'; I haven't had an urgent need for one yet. FWIW, the guy who's using it has one of the nicest RV8s I've ever seen, and doesn't do anything 'half-way'. If it's good enough for him...

Charlie

chaskuss(at)yahoo.com
Guest

Posted: Thu Oct 01, 2020 6:31 am Post subject: voltage monitor

Bob,

Here are two offerings with the ability to handle Lithium batteries, which actually run about 1 volt above AGM and standard flooded batteries. Both are small, rugged and inexpensive.



https://gammatronixltd.com/epages/bae94c71-c5b6-4572-89a1-e89006e78fbe.sf/en_GB/?ObjectPath=/Shops/bae94c71-c5b6-4572-89a1-e89006e78fbe/Categories/Category1



http://roadstercycle.com/Motorcycle%20voltage%20monitor.htm



Per Shorai's web site, their LiFe batteries are fully charged at 14.34 volts, as opposed to 13.2 volts for an AGM or flooded lead/acid battery. See web link below



https://shoraipower.com/faq



From that page, click on the question          Q. Can I use Lead-Acid battery chargers or charger/tenders?



You will see Shorai's charging table.



Charlie K

            

                                                                                        On Thursday, October 1, 2020, 09:52:58 AM EDT, bobnoffs <icubob(at)gmail.com> wrote:                

                



                



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



hi all,



 i have earthx batteries and would like to install a voltage warning separate from my eis. the device must  activate below 13.5 volts . does anyone have any recommendations? i would think something is out there but i haven't seen it.



 thanks, bob noffs



Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=498614#498614



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rparigoris

Joined: 24 Nov 2009
Posts: 792

Posted: Thu Oct 01, 2020 9:59 am Post subject: Re: voltage monitor

Hi Bob I don't know what type of regulator you have, but I have a B&C LR3D that B&C calibrated the Low Voltage Warning for LiFe and also have a B&C AVC1 for Rotax 914 internal generator that you can select LiFe Low Voltage Warning. I'm using a Earth-X 680C. Ron P.

bobnoffs

Joined: 04 Jul 2012
Posts: 132
Location: northern wi.

Posted: Fri Oct 02, 2020 2:33 am Post subject: Re: voltage monitor

i ordered the  tom top unit. for $5 i gotta see how it works. 

  talked to perihelion and i believe they can build  their ''idiot light'' to my specs.this is a panel light with the electronics self contained. 

 any more suggestions i would like to hear.

 thanks, bob noffs

skywagon185(at)gmail.com
Guest

Posted: Sat Oct 03, 2020 12:38 pm Post subject: voltage monitor

I personally like the idea of a panel light that will make you aware of Under and well as Over voltage conditions.

I have experienced an under voltage on start up. Caused by a defective main circuit breaker that opened, but did not show an indication that it had mysteriously opened.Â  Luckily, before beginning the taxi, I noted the amp/volt meter was amiss.

Tested the CB and could not get it to reset.Â  Installed new CB and had no additional problems.

On Fri, Oct 2, 2020 at 3:41 AM bobnoffs <icubob(at)gmail.com (icubob(at)gmail.com)> wrote:



 	  Quote: 	
		  --> AeroElectric-List message posted by: "bobnoffs" <icubob(at)gmail.com (icubob(at)gmail.com)>

 

 i ordered theÂ  tom top unit. for $5 i gotta see how it works. 

 Â  talked to perihelion and i believe they can buildÂ  their 'idiot light' to my specs.this is a panel light with the electronics self contained. 

 Â any more suggestions i would like to hear.

 Â thanks, bob noffs

 

 

 

 

 Read this topic online here:

 

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nuckolls.bob(at)aeroelect
Guest

Posted: Sat Oct 03, 2020 1:05 pm Post subject: voltage monitor

At 03:35 PM 10/3/2020, you wrote:

  	  Quote: 	
		  I personally like the idea of a panel light that will make you aware of Under and well as Over voltage conditions.

 I have experienced an under voltage on start up. Caused by a defective main circuit breaker

 that opened, but did not show an indication that it had mysteriously opened. 	


   Then I take it that your system was not fitted

   with active notification of low voltage. This

   feature is the FIRST if not the ONLY voltage

   sensing/indicating device NECESSARY for flight

   operations.



   Preferably, this light is bright (sunlight viewable)

   and located well within peripheral vision of the pilot.

   Further, it should flash at 2-3 times per second

   (a legacy value for optimal attention getting

   arrived at by numerous human factors studies ).



   This light has been a no-extra-charge built in feature

   of virtually all B&C alternator controllers. From

   day-one (about 35 years ago). It was B&C's mission that

   no customer would be without BOTH low volts and

   over volts management.



  Luckily, before beginning the taxi, I noted the amp/volt meter was amiss.

  	  Quote: 	
		  Tested the CB and could not get it to reset.Â  Installed new CB and had no additional problems. 	


  Yes, there was an element of luck associated with

  that experience. I'm pleased the event resolved

  without a tense-day-in-the-cockpit.



  Along with active notification of low volts, you

  should plan on independent management of an over

  voltage condition with a system that disables

  the alternator within 500 milliseconds of having

  exceeded 16 volts.



  Depending on design parameters of the designer,

  the ov event will be over very soon thus leaving

  you with a low volts condition that will be

  annunciated as cited above.



  Fit your airplane with those two features and

  all the other voltmeters, ammeters, beeps

  and squawks from the panel mounted goodies

  become mere icing on the cake.



  



 

   Bob . . .

bobnoffs

Joined: 04 Jul 2012
Posts: 132
Location: northern wi.

Posted: Sun Oct 04, 2020 3:42 am Post subject: voltage monitor

since my first post perihelion design has let me know that their idiot

light can be made to any high/low settings. pretty slick fix. 2 leads [i

assume] and it all fits in a .55'' panel hole. light can be ordered

flashing or steady.



On Sat, Oct 3, 2020 at 4:11 PM Robert L. Nuckolls, III <

nuckolls.bob(at)aeroelectric.com> wrote:



[quote] At 03:35 PM 10/3/2020, you wrote:



 I personally like the idea of a panel light that will make you aware of

 Under and well as Over voltage conditions.

 I have experienced an under voltage on start up. Caused by a defective

 main circuit breaker

 that opened, but did not show an indication that it had mysteriously

 opened.

   Then I take it that your system was not fitted

   with active notification of low voltage. This

   feature is the FIRST if not the ONLY voltage

   sensing/indicating device NECESSARY for flight

   operations.



   Preferably, this light is bright (sunlight viewable)

   and located well within peripheral vision of the pilot.

   Further, it should flash at 2-3 times per second

   (a legacy value for optimal attention getting

   arrived at by numerous human factors studies ).



   This light has been a no-extra-charge built in feature

   of virtually all B&C alternator controllers. From

   day-one (about 35 years ago). It was B&C's mission that

   no customer would be without BOTH low volts and

   over volts management.



  Luckily, before beginning the taxi, I noted the amp/volt meter was amiss

bobnoffs

Joined: 04 Jul 2012
Posts: 132
Location: northern wi.

Posted: Sun Oct 04, 2020 7:58 am Post subject: Re: voltage monitor

the rub with low voltage indicators is that they set their low voltage for lead acid batteries. this is too low and useless for earthx lipo. low voltage warning must go on below 13.5 volts. when i started this post i talked to b and c about a warning system they had. the voltage was not adjustable and set for lead acid......no good for lipo. b and c said that most electronics is adjustable today and there was never a market for a higher low warning. my system is adjustable but i do not want to probe my ecu with my computer just to make a limit change. 

 earthx users....what's in your wallet? er i mean low voltage setting?

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Oct 04, 2020 9:26 am Post subject: voltage monitor

At 10:58 AM 10/4/2020, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "bobnoffs" <icubob(at)gmail.com>



 the rub with low voltage indicators is that they set their low voltage for lead acid batteries. this is too low and useless for earthx lipo. low voltage warning must go on below 13.5 volts. when i started this post i talked to b and c about a warning system they had. the voltage was not adjustable and set for lead acid......no good for lipo. b and c said that most electronics is adjustable today and there was never a market for a higher low warning. my system is adjustable but i do not want to probe my ecu with my computer just to make a limit change. 

  earthx users....what's in your wallet? er i mean low voltage setting?' 	


   Not sure I understand this. Check out this family of

   discharge plots on 3 brands of LiFePo4 batteries

   including an EarthX.



  https://tinyurl.com/y4nsp8lr



   Looks to me like 13.5V is still a good number.



 

 

   Bob . . .

bobnoffs

Joined: 04 Jul 2012
Posts: 132
Location: northern wi.

Posted: Sun Oct 04, 2020 10:10 am Post subject: Re: voltage monitor

without any mod the ''idiot light'' comes preset to warn below 13.0 volts. in a lead acid set up this would catch the alternator soon after it went off line and a lead acid would have most of its charge left. when a lipo drops below 13 volts a lot of its charge is already been used. the goal is to catch the alternator going out, not to monitor system voltage. my engine needs a battery or a working alternator to keep running.

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Oct 04, 2020 10:29 am Post subject: voltage monitor

At 01:10 PM 10/4/2020, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "bobnoffs" <icubob(at)gmail.com>



 without any mod the 'idiot light' comes preset to warn below 13.0 volts. in a lead acid set up this would catch the alternator soon after it went off line and a lead acid would have most of its charge left. when a lipo drops below 13 volts a lot of its charge is already been used. 	


   Can you confirm that assertion from the

   data offered in the three plots I've

   posted?



  	  Quote: 	
		  the goal is to catch the alternator going out, not to monitor system voltage. my engine needs a battery or a working alternator to keep running. 	


   The testing I've done suggests that

   there MIGHT be a bit of delay in the

   LV WARN response . . . but it's minimal.



   An LV condition is not a high pucker-factor

   event. After the alternator

   quits you can finish your cup of coffee

   and sandwich,  fold the map (if you still use one)

   and then proceed to implement plan-b.



   Conducting a lightning-fast response to the

   light would have no measurable effect on

   the outcome of your flight.



   This is true of what ever type of battery 

   chemistry is on board. This is why I've

   advised against numerous schemes for automatic

   responses to low voltage. Such features only

   add complexity that demands pre-flight testing

   while failing to reduce risk. 



 

   Bob . . .

ceengland7(at)gmail.com
Guest

Posted: Sun Oct 04, 2020 11:09 am Post subject: voltage monitor

On 10/4/2020 1:27 PM, Robert L.       Nuckolls, III wrote:

     

      	  Quote: 	
		                At 01:10 PM 10/4/2020, you wrote:

          	  Quote: 	
		  -->           AeroElectric-List message           posted by: "bobnoffs" <icubob(at)gmail.com> (icubob(at)gmail.com)

           

           without any mod the 'idiot light' comes preset to warn below           13.0 volts.           in a lead acid set up this would catch the alternator soon           after it went           off line and a lead acid would have most of its charge left.           when a lipo           drops below 13 volts a lot of its charge is already been used.         	
         

           Can you confirm that assertion from the

           data offered in the three plots I've

           posted?

         

          	  Quote: 	
		  the goal is to           catch the           alternator going out, not to monitor system voltage. my engine           needs a           battery or a working alternator to keep running. 	
         

           The testing I've done suggests that

           there MIGHT be a bit of delay in the

           LV WARN response . . . but it's minimal.

         

           An LV condition is not a high pucker-factor

           event. After the alternator

           quits you can finish your cup of coffee

           and sandwich,  fold the map (if you still use one)

           and then proceed to implement plan-b.

         

           Conducting a lightning-fast response to the

           light would have no measurable effect on

           the outcome of your flight.

         

           This is true of what ever type of battery 

           chemistry is on board. This is why I've

           advised against numerous schemes for automatic

           responses to low voltage. Such features only

           add complexity that demands pre-flight testing

           while failing to reduce risk. 

         

                

             Bob . . .            	
     

     I think I see his point. If the 'stock' alert point is 13V, the     EarthX chart shows that to be at about the 3 AH point of the curve     with total AH capacity of about 11AH when looking at the higher     discharge rates you'd expect from an electronic injection system.     Not a big deal if there's a backup alternator, but being down     roughly 1/3 before notification could be a big deal if you're     depending on battery for backup.

     

     Charlie

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

chaskuss(at)yahoo.com
Guest

Posted: Sun Oct 04, 2020 11:23 am Post subject: voltage monitor

Bob,

 I suggest to view Shorai's FAQ page linked below.



https://shoraipower.com/faq



 Scroll down and click on the question:    Q. Can I use Lead-Acid battery chargers or charger/tenders?



View the chart on the right side of the page. Note that at 13.0 volts, these LiFe batteries have less than 40% charge left.



Charlie K





            

                                                                                        On Sunday, October 4, 2020, 02:45:15 PM EDT, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com> wrote:                

                



                



                At 01:10 PM 10/4/2020, you wrote:

 	  Quote: 	
		  --> AeroElectric-List messageposted by: "bobnoffs" <icubob(at)gmail.com>



without any mod the 'idiot light' comes preset to warn below 13.0 volts.in a lead acid set up this would catch the alternator soon after it wentoff line and a lead acid would have most of its charge left. when a lipodrops below 13 volts a lot of its charge is already been used. 	


  Can you confirm that assertion from the

  data offered in the three plots I've

  posted?



 	  Quote: 	
		  the goal is to catch thealternator going out, not to monitor system voltage. my engine needs abattery or a working alternator to keep running. 	


  The testing I've done suggests that

  there MIGHT be a bit of delay in the

  LV WARN response . . . but it's minimal.



  An LV condition is not a high pucker-factor

  event. After the alternator

  quits you can finish your cup of coffee

  and sandwich,  fold the map (if you still use one)

  and then proceed to implement plan-b.



  Conducting a lightning-fast response to the

  light would have no measurable effect on

  the outcome of your flight.



  This is true of what ever type of battery 

  chemistry is on board. This is why I've

  advised against numerous schemes for automatic

  responses to low voltage. Such features only

  add complexity that demands pre-flight testing

  while failing to reduce risk. 

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Oct 04, 2020 1:21 pm Post subject: voltage monitor

 	  Quote: 	
		  I think I see his point. If the 'stock' alert point is 13V, the EarthX chart shows that to be at about the 3 AH point of the curve with total AH capacity of about 11AH when looking at the higher discharge rates you'd expect from an electronic injection system. Not a big deal if there's a backup alternator, but being down roughly 1/3 before notification could be a big deal if you're depending on battery for backup. 	


   Don't know where the 13.0 point comes from. Both

   AEC and B&C have used 13.5 for a couple of decades.



   But okay, let's assume 13.0



   See tabular data text file.  The ETX36 with a 5A

   load on it will fall to 13.0 in about 40 seconds.

   The image file is from plotred data of the same

   test:



   Kinda hard to zero in on the finer details of a

   couple hour run but it shows that at 67 seconds,

   the battery was down to 12.99 with an expenditure

   of approx 0.1 AH



   Keep in mind that voltage monitoring at

   the bus is always tens of millivolts HIGHER

   than battery voltage . . . with a similar

   departure to the LOWER side during DISCHARGE

   conditions.



   So assuming one had a LV reporting system that

   was not adjustable but accurate to 100 millivolts

   or so at 13.0, the resulting delay between

   alternator failure and annunciation is still

   timely and 'wasted' energy is trivial.

   



   

   



 

   Bob . . .

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nuckolls.bob(at)aeroelect
Guest

Posted: Sun Oct 04, 2020 1:33 pm Post subject: voltage monitor

At 02:18 PM 10/4/2020, you wrote:

  	  Quote: 	
		  Bob,

 I suggest to view Shorai's FAQ page linked below.



  https://shoraipower.com/faq



 Scroll down and click on the question: Q. Can I use Lead-Acid battery chargers or charger/tenders?



 View the chart on the right side of the page. Note that at 13.0 volts, these LiFe batteries have less than 40% charge left. 	


  That's an open circuit, no-load voltage that speaks

  to state of charge. That's not a milestone voltage

  for a fully charged battery under load.



  Two completely different conditions



 

 

   Bob . . .

bobnoffs

Joined: 04 Jul 2012
Posts: 132
Location: northern wi.

Posted: Sun Oct 04, 2020 1:50 pm Post subject: Re: voltage monitor

hi all,

 according to the graph posted bob is right about the very small current drained. 

this is not at all how earthx describes  their batteries. earthx recommends  that low voltage monitors light up below 13.5 volts.

 on the b and c web site they sell an over/under voltage sensor model bc207. the low voltage light trips at 12.5 volts according to their description.

  everything i have learned about the lipo batteries has said they hold their voltage while discharging. i have always seen a much larger % drop advertised.time for me to call earthx.

ceengland7(at)gmail.com
Guest

Posted: Sun Oct 04, 2020 2:17 pm Post subject: voltage monitor

On Sun, Oct 4, 2020 at 4:28 PM Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:



 	  Quote: 	
		     	  Quote: 	
		  I think I see his point. If the 'stock' alert point is 13V, the EarthX chart shows that to be at about the 3 AH point of the curve with total AH capacity of about 11AH when looking at the higher discharge rates you'd expect from an electronic injection system. Not a big deal if there's a backup alternator, but being down roughly 1/3 before notification could be a big deal if you're depending on battery for backup. 	


 Â  Don't know where the 13.0 point comes from. Both

 Â  AEC and B&C have used 13.5 for a couple of decades.



 Â  But okay, let's assume 13.0



 Â  See tabular data text file.Â  The ETX36 with a 5A

 Â  load on it will fall to 13.0 in about 40 seconds.

 Â  The image file is from plotred data of the same

 Â  test:



 Â  Kinda hard to zero in on the finer details of a

 Â  couple hour run but it shows that at 67 seconds,

 Â  the battery was down to 12.99 with an expenditure

 Â  of approx 0.1 AH



 Â  Keep in mind that voltage monitoring at

 Â  the bus is always tens of millivolts HIGHER

 Â  than battery voltage . . . with a similar

 Â  departure to the LOWER side during DISCHARGE

 Â  conditions.



 Â  So assuming one had a LV reporting system that

 Â  was not adjustable but accurate to 100 millivolts

 Â  or so at 13.0, the resulting delay between

 Â  alternator failure and annunciation is still

 Â  timely and 'wasted' energy is trivial.

 Â  



 Â  

 Â  



 

 Â  Bob . . .

	
I think he's using the EarthX PC680 relacementÂ battery. I used EarthX's chart for their PC680 replacement, here:

https://earthxbatteries.com/earthx_manual.pdf



and assumed ~12-14 A load, which is typical for full electronic engine control with electronic injection. According to EarthX the 680 replacement hovers around 13 V until around 3 AH has been depleted.Â 

You'd know a lot better than me where the LoVolts setpoint is with B&C stuff; that's why I said 'if'. 

Charlie

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Oct 04, 2020 2:33 pm Post subject: voltage monitor

At 04:50 PM 10/4/2020, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "bobnoffs" <icubob(at)gmail.com>



 hi all,

  according to the graph posted bob is right about the very small current drained. 

 this is not at all how earthx describes  their batteries. 	


   Can you point us to the download for

   information that gives you concern?



  	  Quote: 	
		  earthx recommends  that low voltage monitors light up below 13.5 volts. 	


   B&C and I both have promoted that lv setpoint

   value for decades . . .



  	  Quote: 	
		   on the b and c web site they sell an over/under voltage sensor model bc207. the low voltage light trips at 12.5 volts according to their description.

  	
  That device was originally crafted

   for ultralights about 30 years ago.

   In fact, it was the first, stand-alone

   monitor device produced there.

   It was never intended for installation

   in 'real' airplanes. I really wish

   they didn't sell that any more but

   I think Aircraft Spruce shows it in

   their catalog. NOT RECOMMENDED FOR

   NEW DESIGN.



  	  Quote: 	
		   everything i have learned about the lipo batteries has said they hold their voltage while discharging. 	


   And in what way does the data I've posted

   argue with that?



   The AeroVoltz plot shows a working range

   on the order of 13.2 to 12.5 volts. 



   Miady 13.2 to about 12.0



   EarthX from 13.2 to 12.5



   Where are you going to find anything

   flatter for a discharge curve? All three

   deliver power within a 5% or smaller

   window.



 I have always seen a much larger % drop advertised.time for me to call earthx.



    . . . and ask what? Help me understand

   your question. Before you seek verbal

   guidance, let us examine data-in-print

   and data-measured so that disconnects can

   be clearly articulated. I'd be happy

   to call them myself if there are real

   points of contention.



   I've talked to both EarthX and Shorai

   numerous times but a considerable time

   ago . . . wouldn't mind renewing some

   contacts.



 

   Bob . . .

kenryan

Joined: 20 Oct 2009
Posts: 426

Posted: Sun Oct 04, 2020 2:51 pm Post subject: voltage monitor

From:Â Technical Manual for Model No. LR3D-14 and LR3D-28 Linear RegulatorWith Over-Voltage Protection, Low-Voltage Sensing, And Field-Adjustable Charging Voltage

"The LV warning light will begin to flash when the voltage sensed at terminal 3 drops to approximately 12.7V and below"

Disregard if this is not relevant to this discussion.

On Sun, Oct 4, 2020 at 2:26 PM Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote:



 	  Quote: 	
		  



On Sun, Oct 4, 2020 at 4:28 PM Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:



 	  Quote: 	
		     	  Quote: 	
		  I think I see his point. If the 'stock' alert point is 13V, the EarthX chart shows that to be at about the 3 AH point of the curve with total AH capacity of about 11AH when looking at the higher discharge rates you'd expect from an electronic injection system. Not a big deal if there's a backup alternator, but being down roughly 1/3 before notification could be a big deal if you're depending on battery for backup. 	


 Â  Don't know where the 13.0 point comes from. Both

 Â  AEC and B&C have used 13.5 for a couple of decades.



 Â  But okay, let's assume 13.0



 Â  See tabular data text file.Â  The ETX36 with a 5A

 Â  load on it will fall to 13.0 in about 40 seconds.

 Â  The image file is from plotred data of the same

 Â  test:



 Â  Kinda hard to zero in on the finer details of a

 Â  couple hour run but it shows that at 67 seconds,

 Â  the battery was down to 12.99 with an expenditure

 Â  of approx 0.1 AH



 Â  Keep in mind that voltage monitoring at

 Â  the bus is always tens of millivolts HIGHER

 Â  than battery voltage . . . with a similar

 Â  departure to the LOWER side during DISCHARGE

 Â  conditions.



 Â  So assuming one had a LV reporting system that

 Â  was not adjustable but accurate to 100 millivolts

 Â  or so at 13.0, the resulting delay between

 Â  alternator failure and annunciation is still

 Â  timely and 'wasted' energy is trivial.

 Â  



 Â  

 Â  



 

 Â  Bob . . .

	
I think he's using the EarthX PC680 relacementÂ battery. I used EarthX's chart for their PC680 replacement, here:

https://earthxbatteries.com/earthx_manual.pdf



and assumed ~12-14 A load, which is typical for full electronic engine control with electronic injection. According to EarthX the 680 replacement hovers around 13 V until around 3 AH has been depleted.Â 

You'd know a lot better than me where the LoVolts setpoint is with B&C stuff; that's why I said 'if'. 

Charlie

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