Older 5 KNOB Magnum AGS Failure

[96 EVO]

6 minutes ago, hex_nut said:

Ben

BOGO is an acronym for Buy One Get One.  Tom is simply saying it is free advice.

Thanks Richard!

Never heard that one before!

[Dr4Film]

I haven't taken a close look at it but I will. Now that I think about it, there are two storage bays and two wheel wells just to get to the battery bay so it is very possible I guess.

I will put some measuring tape on it this week and report back.

[Tom Cherry]

12 hours ago, pwhittle said:

Hi Richard,

Same as on ours.

Measure it out, allowing the distance to the center of the coach to run forward, and see how close your estimate is to mine.

At least with Lithium, we may have an option to put the batteries in that bay.

Paul

OK….my take….and what Magnum told me.  The AGS Module is NOT, when using the REMOTE, taking any signal from a remote on the battery.  Whatever value is being input or provided to the Magnum remote….that is the Digital or Multiplexed value or control for the AGS….regardless of old 4 or new AGS-N.

Therefore, if you use the remote readout as the “gospel” or the set parameter for “start” or turn on, then, as I posted, you need to know how that correlates to the real world of the HOUSE BANK.  That takes into account the “innate error”, as Magnum verified, of the remote meter…..versus the Battery Voltage.

NEXT….you have to know how much voltage drop you are experiencing ….UNDER LOAD. You then set the START voltage based on that….but you subtract 0.1 or one tenth.  The Magnum reaction or “OMG, START should be based or calculated that way.

PUT another way.  Lets say you want to start when the batteries reach 50% SOC.  That is defined as the “recovery” voltage….NOT the under load voltage.  Per the charts….the SOC for 50% is about 12 VDC.  LETS ASSUME the Magnum meter is perfect….your DVM and it are dead on.  NOW, lets assume that your UNDER LOAD Voltage is 11.9 VDC…..and you KNOW, through testing that when that stabilizes…..or remains constant….that the bank will recover to 12.0.  SO….as LONG as the UNDER LOAD voltage is 11.9….OK.  BUT when the under load voltage hits 11.8…..then it is time to start and recharge…NOT 11.9…

SO, per Magnum and Trojan, you set the AGS to 11.8. The Magnum has a timed delay…..so maybe after 2 minutes….assuming the voltage is stabile….and it reads 11.8….BINGO the genny starts.  You had a brief, inconsequential time of a couple of minutes where the SOC dropped to say 45% or so….but you met the objective of “recharge” when SOC is LESS than 50%.

OK….hope that helps…..

NEXT UP….you need to know the delta or error or difference between the REAL DVOM House voltage and what the Magnum remote reads….once you know that is Zero or maybe 0.1 or probably closer to 0.2…..then you adjust or use the correlated Remote voltage.  Worse case….say there is a 0.2 VDC error.  You set your Magnum based on expecting it to be 11.8….OPPS, in reality…the Battery Voltage is higher…..as the Magnum remote TYPICALLY, per Magnum, reads LOWER.  Thus, 11.8 on the REMOTE is actually 12.0 on the DVM.  NOW to correlate and achieve your 50% SOC, you have to set the VOLTAGE LOWER….0.2 ERRROR…..OMG….that will be 11.6.  BLASPHEMY.  NOPE reality.  

SO when someone says…..NEVER SET BELOW 12.0….there are two misconceptions.  First….that should be 11.9….as when 12.1 DROPS to 12.09….that is a 12…  NOPE….when the UNDER LOAD Hits 11.8….that is the correct value.

second….the meters are NOT PERFECT.

REALITY….Monaco put the AGM’s up front or back in the rear.  If in manual, I THINK that the placement here and voltage issues or drops are ONLY Relevant when you use it in manual mode.  In the REMOTE MONITOR controlled mode….the REMOTE is the “Voltage Keeper”.  Call Magnum and verify.

SECOND, I have NO IDEA if you have a BMK what the remote wil read compared to the DVOM at the battery.  Test and then adjust….or maybe not needed.

THIRD, @Frank McElroy did a little “rewring”.  I don’t remember exactly why, but he changed it so the actual REMOTE reading has less LOSS.  He will have to chime in.

THATS MY UNDERSTANDING and the explanation and logic of how to properly set the AGS from the remote….

NOW, you see, if your mind took months like mine did to develop snd understand the above scenario……why Magnum decided NOT to “tell the average” owner….but in detailed discussions…..this is how it works…..and Trojan says….when the Under Load voltage….which is NOT the true or recovery voltage…..usually 0.10 - 0.20….you set the AGS to come on 0.1 below that….

 

[Frank McElroy]

11 minutes ago, Tom Cherry said:

THIRD, @Frank McElroy did a little “rewring”.  I don’t remember exactly why, but he changed it so the actual REMOTE reading has less LOSS.  He will have to chime in.

THATS MY UNDERSTANDING and the explanation and logic of how to properly set the AGS from the remote….

NOW, you see, if your mind took months like mine did to develop snd understand the above scenario……why Magnum decided NOT to “tell the average” owner….but in detailed discussions…..this is how it works…..and Trojan says….when the Under Load voltage….which is NOT the true or recovery voltage…..usually 0.10 - 0.20….you set the AGS to come on 0.1 below that….

 

The AGS gets the battery voltage from the large 12 volt battery cable connected to the inverter.  To remove the voltage drop on this line, I connected a dedicated battery sensing wire from the house battery bank to the AGS.

[Jetjockey]

I consider the at  rest voltage to determine where the ags start voltage should be . If you remove the loads when you hit say 11.6v then observe where the voltage recovers to possibly 12.2 to 12.4 . You can then set the start voltage so the ags starts when it should with out starting too early unecessarily. Those observations no doubt at different in different units.I also use my victron system to monitor start and house batteries directly too as an ags start voltage directly. My ags and inverter are xantrex and likely are a little different.

I am considering attaching a remote reading voltage meter at the generator starter or just volt meter that cable to establish voltage drop both static and under starting load. Just for knowledge sake. If the gen does not start I could do a battery cross start tie or start the motorhome momentarily to do so. 
lots of options .

Edited May 8 by Jetjockey

[Tom Cherry]

20 minutes ago, Jetjockey said:

I consider the at  rest voltage to determine where the ags start voltage should be . If you remove the loads when you hit say 11.6v then observe where the voltage recovers to possibly 12.2 to 12.4 . You can then set the start voltage so the ags starts when it should with out starting too early unecessarily. Those observations no doubt at different in different units.I also use my victron system to monitor start and house batteries directly too as an ags start voltage directly. My ags and inverter are xantrex and likely are a little different.

I am considering attaching a remote reading voltage meter at the generator starter or just volt meter that cable to establish voltage drop both static and under starting load. Just for knowledge sake. If the gen does not start I could do a battery cross start tie or start the motorhome momentarily to do so. 
lots of options .

We’re on the same page, except the real world is this.  The normal load, for discharge, per Trojan, us supposed to be 10% or so of the total bank’s capacity.  I THINK that is correct….Lithiums or AGM’s may be different….read the owner’s manual for them.

OK….typically, during at least 5 different run down or exercising tests….this is real world.

Have a 450 Watt halogen work light.  If you divide 450 watts, by the battery voltage, that is a little less than 40 Amps.  OK…that is close enough so 10% of my 4 bank amp hours is 45.  DRIVE ON.

NOW, when the DVOM battery voltage drops to 11.9….I stop….I might let it run and see a 11.8 blip.  So….remove load.  If you disconnect the jumpers and wait maybe 20 minutes….all of this is what Trojan told me or I asked for confirmation…..then measure the individual batteries.  Obviously half the voltaage, but if you read the SOC table….and do a hydrometer test….they will be right at 50% discharged.  That was the goal…

NOW, check the electrolyte…..perfunctory but good practice.  Rarely have to add.  I have a dowel with a scribed mark.  That mark, when you put it in a cell and it touhes the plate….is exactly half way between the plate and the bottom of the well….where Trojan says to always fill to.

Install Jumpers….recharge….when FLOAT…..then pull Jumpers….and wait.  They read per DVOM and hydrometer close to 100%.  Hydrometer is usually a bit higher….or way better, but Voltage is dead on.

NOW….that is real world…plus how Trojan says do it. In reality….one SHOULD turn off both disconnects BEFORE removing or reinstalling  jumpers.  If there is an arc and you have an Intellitec MPX, it may go into START UP….and if there is a microsecond interruption….the IPX or CPU or Modules go or can go haywire…. I have HAD to kill the house switch and then wait and restart for a clean “boot” or startup sequence.

NOW…in your example, the variations are NORMAL….except the true way to exercise and also evaluate your bank is with a constant load.

NOW….there is a timed circuit on the Magnum AGS.  That allows for quick hits of high current….and that is called a “smoothing” timer…so, it does NOT say.. OMG.  Prevents false positives or unnecessary AGS Start Signal.  But, if your Low Battery Cutoff is set too high, you will, based on either instantaneous or shorter timer, shut down the whole system.

I will ask Magnum for a review to confirm…..as well as where or what powers the remote….

[Ivan K]

With my Xantrex I know the remote reads up to 0.2v lower when inverting so my AGS is set at 11.8V. Even then, the voltage has to stay below threshold for 30s, to ignore momentary drops, so I have some time to run an extra heavier load before the starting sequence even begins. 

[96 EVO]

11 minutes ago, Ivan K said:

With my Xantrex I know the remote reads up to 0.2v lower when inverting so my AGS is set at 11.8V. Even then, the voltage has to stay below threshold for 30s, to ignore momentary drops, so I have some time to run an extra heavier load before the starting sequence even begins. 

It's too bad they didn't make that 30sec adjustable.

I would be able to set it to 5min (time it takes to brew my pot of coffee). 

Then I'd be able to set my AGS around 11.8-12.0V!

[dandick66]

17 hours ago, 96 EVO said:

Thanks Richard!

Never heard that one before!

Here you go, Ben.

 

[96 EVO]

Several years ago, I received a BOGO, ESCO lyght 50A transfer switch ordered through Amazon ( they didn't either believe me, or care, when I informed them there was two ATS in the box they shipped) 😃!

Winsorbill is running the second switch!

[Tom Cherry]

UPDATES....and some of the FOG cleared...but JUST when I thought it was clear...a STORM Moved in.

First.  The AGS, regardless of the older 5 KNOB AGS or the AGS-N... uses the HOUSE BATTERY Voltage.  It is SUPPOSED to be wired directly to the HOUSE BANK Connections.  It DOES NOT receive input from the Remote.  Terminals 3 and 4 are the VOLTAGE Sensing leads....on the AGS hard wired connector.  NOW...all the debate about running wires and such....Magnum and Frank McElroy cleared this up.  The amount of Voltage Drop one would get on the TWO #12 wires running from the Batteries to the FRONT (mine is in the FRB) and Frank's is in the rear...adjacent to his Inverter is MINISCULE.  This is a SENSING Voltage....and NOT a load carrying one.  SO, either location...properly wired, will work and there would be maybe few MilliVolts difference in one in the front vs the rear.

SECOND...  AND THIS IS THE KILLER...  Even MAGNUM was confused on this.

If you have a 2008 (at least on the Dynasty) 5 KNOB one....then the Magnum Remote was totally different and functioned differently.  If you have the the SAME or same "VINTAGE" remote as on the 2008 Dynasty....then HOW you set the AGS and it works is TOTALLY DIFFERENT.  The REMOTE only "enables it"....  You can NOT set the parameters...

NOW, on my 2009, I have the SAME AGS.  BUT, my ME-RC was capable of PROGRAMMING IT.  If you look at the two photos....one from the 2008 Dynasty and mine from the 2009 Camelot....then the mystery is solved.

THE POINT, other than the conflicting or dueling remotes...

The AGS will read the Battery Voltage.  If you have EITHER remote... You have to then set the ON point to a LOWER Voltage...and you have to understand the UNDER LOAD compared to RECOVERY....as well as go ONE TENTH lower on the START.  See the previous posts..

This should clear it up...or it does for me...

[pwhittle]

19 hours ago, Frank McElroy said:

The AGS gets the battery voltage from the large 12 volt battery cable connected to the inverter.  To remove the voltage drop on this line, I connected a dedicated battery sensing wire from the house battery bank to the AGS.

Hi Frank,

What inverter let you do that? I have a Magnum MS2812..

I get well over 1V difference between the Inverter voltage and the BMK voltage under high current, like running the microwave.

Paul

[Frank McElroy]

1 hour ago, pwhittle said:

Hi Frank,

What inverter let you do that? I have a Magnum MS2812..

I get well over 1V difference between the Inverter voltage and the BMK voltage under high current, like running the microwave.

Paul

Yes, I have the Magnum MS2812 and yes, before adding a dedicated sensing wire, I'd see the same voltage drop at the AGS module because Monaco tapped into the battery voltage at the Magnum inverter instead of a dedicated battery sensing wire.

[Tom Cherry]

4 hours ago, Frank McElroy said:

Yes, I have the Magnum MS2812 and yes, before adding a dedicated sensing wire, I'd see the same voltage drop at the AGS module because Monaco tapped into the battery voltage at the Magnum inverter instead of a dedicated battery sensing wire.

Funny, you should clarify this.  The Magnum tech, yesterday, said the CORRECT WAY, per the install print or preferred, was a direct line to House bank…. I did NOT verify from the instructions on the old or new AGS….so….if it ain’t that way….the tech said HOUSE and NOT Inverter….as I asked that question specifically….

BUT, said that many techs or installations just picked up the voltage from the Inverter battery terminals.

SO, once again….Monaco did NOT always follow a supplier’s instructions….like the Intellitec EMS

Thanks….now I know….

[pwhittle]

13 hours ago, Frank McElroy said:

Yes, I have the Magnum MS2812 and yes, before adding a dedicated sensing wire, I'd see the same voltage drop at the AGS module because Monaco tapped into the battery voltage at the Magnum inverter instead of a dedicated battery sensing wire.

Oh. Sense for the AGS, not for the inverter itself. That makes sense.

i don’t know why Magnum did not provide for a battery sense input from the battery to allow for the voltage drop. I recall asking their tech support if there was one on the inverter, and they said there was not.

Paul