Prog Dynamic PD9130V Converter issue

[Pass me]

FYI, a resting battery is fully charged at 12.6V, 50% at ~12.1 V and dead at 10.5V.

AT 12.6V your state of charge is good. Do the capacity recommended by Mark Post # 17, esp. because you indicated that the battery appears to discharge fairly rapid.

Based on your low amp hr. battery I am guessing you are on shore power primarily. If you do have to replace the battery you should evaluate if a deep cycle battery would benefit you.

Jennifer

Ubet I'll do this test soon BUT to avoid damaging the battery (more) my "quit the test" guage should be when battery voltage reaches 50% SOC, i.e. 12.23V. I'm curious then why 10.5V is mentioned. Am I missing something here?

 

[ferfer]

First the numbers above are for flooded lead acid battery. Maintaining battery voltage closer to the 12.6 V but above the 50% discharge voltage enhances battery life. The 10.5V is just a reference point for a very dead battery & I suggest you do not want to go there. I am not sure where your battery voltage soc are coming from but they are nearer to resting AGM batteries.

House batteries are for running 12V systems when not on shore power / generator or by your PD9130V convert/charger when on power. When batteries supply 12V power is the reason the number of amp hours is important. If you boondock you want a true deep cycle battery with high amp hr. (or reserve capacity). The starting battery (CCA) have high amps for a short time.

Looking forward to capacity test results.

Jennifer

 

[Pass me]

First the numbers above are for flooded lead acid battery. Maintaining battery voltage closer to the 12.6 V but above the 50% discharge voltage enhances battery life. The 10.5V is just a reference point for a very dead battery & I suggest you do not want to go there. I am not sure where your battery voltage soc are coming from but they are nearer to resting AGM batteries.

House batteries are for running 12V systems when not on shore power / generator or by your PD9130V convert/charger when on power. When batteries supply 12V power is the reason the number of amp hours is important. If you boondock you want a true deep cycle battery with high amp hr. (or reserve capacity). The starting battery (CCA) have high amps for a short time.

Looking forward to capacity test results.

Jennifer

Thanks Jennifer, I'm retired and plan to use my 19' trailer exclusively for boondocking from here on in. Available power is a 2100W generator and this 93Ah battery. I plan to use a 2000W Inverter to start the day quietly (1400W AC Kuerig), fish till 2 pm then charge the battery to 80+%. Repeat. My 12V demands are not factored in yet but...some LED lighting, my 3.2A RV furnace on occasion, water pump as req'd, that's about it.
I think it's doable, if not then LAB battery will be upsized or maybe the Lithium option will be looked at. Solar isnt practical as I'm seldom in direct sunlight and the gensets quicker.
Hope this helps explain my needs and intentions here.

 

[ferfer]

Agree you will not know until you evaluate your 12v system requirements. Calculated estimates are everything functioning at 100% and no wire loss vs what you have. The 12V system also controls most (all) control board i.e absorption fridge & thermostat, in addition to lights and whatever power you ask inverter to draw.

Remember to half the battery(s) Ah rating since routinely do not discard below 50% volts.

If you wind up replacing the battery I suggest coming back to the forum for suggestion what might work best for your with your equipment and style of boondocking. If you find current convert/charger takes too long to charge, the multistage will reduce the time and protect battery.

Hope you tell us how all this comes out.
Jennifer

 

[Pass me]

Will do. I don't have that Genius10 just yet, my bench charger allows for 0-15V and 0-60A charge settings. Readout shows 15.8V when set to max V and I'll keep the Amps as low as Readout allows. Battery will be fully charged before hand, caps off and I'm thinking a 12 hr run time.
Stay tuned! Lol....and again thank you all for all your input.

 

[Mark_K5LXP]

My battery doesn't state Ah unfortunately,

Then it's probably not a true deep cycle.

I'm using ~93 Ah ( CCA ÷ 7.2 formula) as my go to.

Yeah, somewhere around 7 gets you close. This isn't a precision process, it's either going to run the load near the spec or it won't.

So use a 5A DC draw to my battery and see if it lasts 20 Hrs, maybe a hair more.

As old as it is, and not being a deep cycle I would set my expectation level towards the "bad" end of the scale. You just may have used up all this battery might have had. But I would run a capacity test anyway just to get an idea how the test works and to have some basis of comparison for whatever capacity this battery has vs how it operated your trailer loads.

use my Voltmeter to watch for 10.5V to avoid 50% or more drain on the battery.

10.5V under load is 100% discharge. This is how battery Ah rating is spec'd.

my "quit the test" guage should be when battery voltage reaches 50% SOC, i.e. 12.23V. I'm curious then why 10.5V is mentioned. Am I missing something here?

Yes. You're confusing resting voltage for voltage under load. The state of charge charts you often see and are usually misapplied are only for when a given battery has sat for 24 hours with no activity. Under load the terminal voltages are different. 50% state of charge under load would be around 11.6V. You could stop testing here I guess, but to get a true picture of capacity you'd run it down to 10.5V. Going below 50% does not damage a battery any more than 20%, 80% or 100%. It's within their operating specification. The caveat here may be it's not a deep cycle battery and isn't up to hundreds of deep discharges. If it can't cut the mustard then you're probably done before you started, because if you have to pamper the thing by limiting current draw and discharge depth, it will be of limited utility anyway (not running your stuff and recharging often).

I plan to use a 2000W Inverter to start the day quietly (1400W AC Kuerig),

Not with this battery you're not. Put a ~130 amp load on a marine battery and you'd be lucky to get a minute or two of operation even with a fresh charge. Your options are to get a much beefier battery or make your coffee on a propane stove. The other loads you describe are well within the capabilities of a modest battery setup.

Mark B.
Albuquerque, NM

 

[John From Detroit]

Call me a Luddite, but there's nothing wrong with using 25 year old technology if it does the same thing as "modern" technology with less fuss and bother. If you're concerned with using obsolete technology go lithium. Lead acid battery technology is over 100 years old.

I know a bit more about Progressive Dynamics as I grew up near the company and my mother did some consulting for them and I was friends with some relatives of the corporations owners.
The technology they used. at least back then, was a tad..er.. Advanced. I am assuming it still is.
For example... Their power supplies (Pre-cursor of the converters) used something called zero threshold switching... IT's a bit harder to do but there are some other issues that.. basically vanish when you switch at zero.

 

[Pass me]

My battery doesn't state Ah unfortunately,

Then it's probably not a true deep cycle.

I'm using ~93 Ah ( CCA ÷ 7.2 formula) as my go to.

Yeah, somewhere around 7 gets you close. This isn't a precision process, it's either going to run the load near the spec or it won't.

So use a 5A DC draw to my battery and see if it lasts 20 Hrs, maybe a hair more.

As old as it is, and not being a deep cycle I would set my expectation level towards the "bad" end of the scale. You just may have used up all this battery might have had. But I would run a capacity test anyway just to get an idea how the test works and to have some basis of comparison for whatever capacity this battery has vs how it operated your trailer loads.

use my Voltmeter to watch for 10.5V to avoid 50% or more drain on the battery.

10.5V under load is 100% discharge. This is how battery Ah rating is spec'd.

my "quit the test" guage should be when battery voltage reaches 50% SOC, i.e. 12.23V. I'm curious then why 10.5V is mentioned. Am I missing something here?

Yes. You're confusing resting voltage for voltage under load. The state of charge charts you often see and are usually misapplied are only for when a given battery has sat for 24 hours with no activity. Under load the terminal voltages are different. 50% state of charge under load would be around 11.6V. You could stop testing here I guess, but to get a true picture of capacity you'd run it down to 10.5V. Going below 50% does not damage a battery any more than 20%, 80% or 100%. It's within their operating specification. The caveat here may be it's not a deep cycle battery and isn't up to hundreds of deep discharges. If it can't cut the mustard then you're probably done before you started, because if you have to pamper the thing by limiting current draw and discharge depth, it will be of limited utility anyway (not running your stuff and recharging often).

I plan to use a 2000W Inverter to start the day quietly (1400W AC Kuerig),

Not with this battery you're not. Put a ~130 amp load on a marine battery and you'd be lucky to get a minute or two of operation even with a fresh charge. Your options are to get a much beefier battery or make your coffee on a propane stove. The other loads you describe are well within the capabilities of a modest battery setup.

Mark B.
Albuquerque, NM

Hey Mark, I'm confused where you get the ~130A load from. I use wattage to reference power requirements so the 1500W AC Keurig requires: W=AxV, 1500÷120=A, A=12.5
BUT Inverter sources 12V not 120 soooo 1500÷12=125A.
Now I understand! I think,lol.
Your 130A allows for systems deficiencies.
Yikes!
Update here. Battery coming out of storage: V=12.1, after charging: V=12.6
After two ~10 hr equalize runs (15.8V, .5A) I'm getting 13.4V. I rested the battery ~8 hrs, voltage reads 13V.
So equalize process did help, Hurrah, lol.
Next is the capacity test, I don't have a 12V 5A draw handy (trailers in storage) can I use the inverter? An AC trouble light/60W bulb should run for 20hrs (60÷12=5). My inverter has under voltage protection factory set at 10V, it will kick out. I'm thinking this will protect my battery. I now know this "under load" voltage is momentary - it will climb when battery is rested. It's super helpful to know 50% SOC under load is ~11.6V, this is my new real world warning via voltmeter when I try a heavy wattage AC appliance.
I will post the results and as always thank you everyone for your time and consideration, it is very much appreciated.

 

[Tulecreeper]

Ubet I'll do this test soon BUT to avoid damaging the battery (more) my "quit the test" guage should be when battery voltage reaches 50% SOC, i.e. 12.23V. I'm curious then why 10.5V is mentioned. Am I missing something here?

When a battery voltage drops to 10.5 volts, the battery is effectively 'dead'.

 

[Gary RV_Wizard]

if I understand you my battery shouldn’t be to bad off even after a prolonged trickle charge? At rest/shore power disconnected it shows ~12.6V or ~75% charged.

12.6v-12.7v is fully charged for a lead-acid battery at rest. Any voltage in excess of that is residual "surface charge" from the active charging cycle.

 

[Tulecreeper]

Thanks for this. My battery doesn't state Ah unfortunately, I'm using ~93 Ah ( CCA ÷ 7.2 formula) as my go to.
So 93 ÷20 = 4.65A for 20 hr.
So use a 5A DC draw to my battery and see if it lasts 20 Hrs, maybe a hair more. And use my Voltmeter to watch for 10.5V to avoid 50% or more drain on the battery.

I've never heard of using the CCA as an indicator of Ah's. If your battery has no Ah rating, then use the Reserve Capacity (RC) to do the math. Multiply the RC times 0.417 and it will get you within an amp hour or two of your capacity.

120 minute RC x 0.417 = ~50Ah

 

[Mark_K5LXP]

Inverter sources 12V not 120 soooo 1500÷12=125A.

Yep.

two ~10 hr equalize runs ... equalize process did help, Hurrah, lol.

You got some boost in voltage so maybe it did wake up some portion of slumbering cells. Where the rubber meets the road is delivered Ah. So on to a capacity test. As a pointer, if a battery has been idle/on float for a while (months) the first few discharge tests won't be to spec. So if the first one comes up a bit short charge it up and run it again to see if it improves. When you get 2 or 3 successive tests in a row that are the same, then that's the number.

I don't have a 12V 5A draw handy can I use the inverter?

Not only can you, I consider it a nearly ideal way to do so. It's not constant current per the spec, likely constant power, but is easily controlled and may have a low voltage cutoff as you mention. The one I use works this way and is the same one I use for all my testing so results from test to test are readily compared. Mix and match different wattage bulbs to dial in the exact current draw you need. The wattage I pick is so the current draw is the C/20 rate at the 50% discharge point (~11.6V). That way the average current from 100% to 0% is the C/20 rate. The inverter being a constant power load the 50% point will occur somewhat past the 50% time point with the remainder getting compressed towards the end so it's not a "perfect" discharge curve. But it is a consistent/repeatable test and can tell you everything you need to know about a battery's merit.

It's super helpful to know 50% SOC under load is ~11.6V, this is my new real world warning via voltmeter when I try a heavy wattage AC appliance.

How much the terminal voltage moves under varying loads is an indicator of internal impedance so there's no real significance to the 50% point. This impedance might be intrinsic based on the size and topology of the battery, it's an consequence of state of charge and an indicator of wear or damage. A new/good/charged battery will be "stiff", dropping little voltage when a load is applied but a weak/old/shot/discharged battery will drop a lot of voltage. After you've tested a few thousand batteries you get a feel for how a battery is doing just watching the voltage during charge and discharge.

Mark B.
Albuquerque, NM

 

[Pass me]

Inverter sources 12V not 120 soooo 1500÷12=125A.

Yep.

two ~10 hr equalize runs ... equalize process did help, Hurrah, lol.

You got some boost in voltage so maybe it did wake up some portion of slumbering cells. Where the rubber meets the road is delivered Ah. So on to a capacity test. As a pointer, if a battery has been idle/on float for a while (months) the first few discharge tests won't be to spec. So if the first one comes up a bit short charge it up and run it again to see if it improves. When you get 2 or 3 successive tests in a row that are the same, then that's the number.

I don't have a 12V 5A draw handy can I use the inverter?

Not only can you, I consider it a nearly ideal way to do so. It's not constant current per the spec, likely constant power, but is easily controlled and may have a low voltage cutoff as you mention. The one I use works this way and is the same one I use for all my testing so results from test to test are readily compared. Mix and match different wattage bulbs to dial in the exact current draw you need. The wattage I pick is so the current draw is the C/20 rate at the 50% discharge point (~11.6V). That way the average current from 100% to 0% is the C/20 rate. The inverter being a constant power load the 50% point will occur somewhat past the 50% time point with the remainder getting compressed towards the end so it's not a "perfect" discharge curve. But it is a consistent/repeatable test and can tell you everything you need to know about a battery's merit.

It's super helpful to know 50% SOC under load is ~11.6V, this is my new real world warning via voltmeter when I try a heavy wattage AC appliance.

How much the terminal voltage moves under varying loads is an indicator of internal impedance so there's no real significance to the 50% point. This impedance might be intrinsic based on the size and topology of the battery, it's an consequence of state of charge and an indicator of wear or damage. A new/good/charged battery will be "stiff", dropping little voltage when a load is applied but a weak/old/shot/discharged battery will drop a lot of voltage. After you've tested a few thousand batteries you get a feel for how a battery is doing just watching the voltage during charge and discharge.

Mark B.
Albuquerque, NM

Super informative as per usual Mark, just when I think I'm closing in on battery 101 you bring me back to reality! Lol
It really is a fascinating science to me, a definite rabbit hole if you will and an enjoyable learning curve.
For now starting tomorrow and using a 60W bulb I'll run 2-3 capacity cycles and post the results.
And lastly your reference to batteries behavior being "stiff" or not is extremely practical, I'll be watching for this when I attempt to place a 1000W+ load through the converter.

 

[Gary RV_Wizard]

Mark has provided excellent guidance, but let me reinforce the practical aspect. The algorithms and measurements are fairly broad indicators, so don't get too hung up on the numbers you get when you test. There are enough variables in actual RV use, e.g. varying amp loads, changing temperatures, and voltage drops, to make actual performance more a matter of educated guesswork rather than science. As Mark said, you have to develop a "feel" for what the various measures or tests will mean in practical terms.

 

[Pass me]

Mark has provided excellent guidance, but let me reinforce the practical aspect. The algorithms and measurements are fairly broad indicators, so don't get too hung up on the numbers you get when you test. There are enough variables in actual RV use, e.g. varying amp loads, changing temperatures, and voltage drops, to make actual performance more a matter of educated guesswork rather than science. As Mark said, you have to develop a "feel" for what the various measures or tests will mean in practical terms.

Ubet. I'm just now getting the idea of "a feel" in the scope of things. Much better than wondering how the damn battery died after a day r two boondocking which is where most of us I'm sure have "been there done that".
My current (pun intended) battery has been named "Guinea Pig" and I'm beginning to believe it will suit my needs for now. More importantly I want to have a comfortable knowledge base when it comes time to replace it.

 

[Mark_K5LXP]

By doing a capacity test you eliminate one of the variables - how big the energy bucket is. From there, if the boondocking run time comes up short you don't have to wonder if it's a bad battery or not. Without doing a capacity test it's like driving around without a gas gauge. You dump energy in and take energy out without really knowing if you're full or empty until the thing konks out. Throw in that batteries can be damaged by improper charging and storage and for many the first indication there's a problem is when the lights go out. Staying on top of how the system is working and simple preventative maintenance goes a long way towards never having the lights go out.

Mark B.
Albuquerque, NM