Hi all,I'm generator charging from need for the first time in my life. It is not hot enough to run the roof air.Here is a bit about the system.Magnum 3000 Hybrid 12 volt to 120 volt with ARC remoteYamaha 3000 sIEB inverter generator4 139 amp-hour surplus acid telecom 12 volt batteries totaling 556 amp-hours. These are a bit unusual as their specific gravity is 1.3 rather than the more normal 1.275. They have a slightly higher voltage.256 watts of solar into a Blue Sky 3024 di controller.voltage monitored with a kill-a-wall unitWattage monitored by an Efergy Elite classic watt meter.Charging rate monitored by the Magnum remote.Conditions:Batteries were not fully charged yesterday and were used overnight. Remote display said 12.5 volts.I started the generator leaving it at maximum output.I made the following observations:Remote went immediately to float charging at 10 ampsLoad was the fridge at 311 watts (2.5 amps)Voltage was 122.I turned off the fridge. No change in charging rate or voltageI increased the load on the system by turning on the water heater 1300 watts (11 amps) voltage 118Charging rate increased to 39 amps.I turned off the water heater and charging amps slowly dropped back down to 10.The "trigger" point for higher amp charging appears to be about 1300 watts. Doing so may double the fuel consumption rate. I'd prefer to avoid this.

Sounds like a programming issue, I'd recommend calling in to Magnum or whatever their new ownership calls them now.I've never had a problem charging like you describe, having to put a load on the system to make mine charge, but I've got the MS2812.Only weird thing I notice on mine while charging, sometimes when it drops from Absorb to Float, the charging amps get stuck at exactly "15" while on the generator. I can have all my switchable dc loads off, and the BMK shows 0 amps going into the battery (per the shunt reading), yet the ARC remote shows 15 amps output on float charge.If I turn the charger off, and on again, sometimes it'll drop to 0, or sometimes it'll stay stuck at 15.Do you have the Magnum BMK as well, or just the charging amp-meter the remote provides? I'm wondering if the actual amperage into your batteries is different than the guesstimate shown on the remote.Next question, how many amps were the solar panels contributing to the system?Last question, in the ARC menus, what do you have your charging mode voltage thresholds set at? Perhaps with the solar coming in and not much load, the Magnum's computer decided the batteries don't need aggressive charging based on the voltage.My ARC will not switch into Absorb until the load gets quite high, dropping the battery voltage, and Bulk comes in at an even lower voltage. I can look in my menus later today for you if you want to compare.In one of the menus, there is an option to force the batteries to charge, equalizer mode or something? I've never done it on my bank, I don't think AGM need an equalizer charge - maybe Mex has some words of wisdom on that subject...

I think PT is saying the Magnum reduces charging at 122v input (some kind of thermal ? protection for the Magnum )turning on the water heater (using genny power not inverter) reduces the yammy output line voltage to under 120v or less and the magnum then turns on and charges the batterieshe just recently got an auto transformer for Boosting low voltage shore power conditionsbut it sounds like he needs to 'BUCK Down' the generator output, because of the finicky Magnumit Is an unusual situationDondon't you have another converter you can plug in in this situation39amps is no where near the max of the magnumIIRC you do have something else that will supplement that 10 amps and get back to near 40amps charge

If I woke up to 12.5 volts I would not be running the generator.Battery does not need to be perfectly 100% charged every day.

while thats true for weekends or part timingget a big bank too low and you could spend a whole lot of time in bulk mode generator run timewith a 20% 12hr use (IF i did not charge during the day) i would be at 60% before bed tonight and 40% tomorrow morningNOT the place i prefer to bei can do that in a bad weather pinch, and the solar does mitigate the situation making it less strenuous than the straight math, and i could limit some of the power drain at night and make (2) with no chargingput that is winter time use, cool weather and no A/C, and less cooling strain on the fridgedifferent routines for different folks

Hi Gordonthree,I've emailed them, and now have had a phone conversation. They did not understand the original email. The tech was intrigued when he finally understood what I was "going on about"I do not have the BMK.Solar was contributing 3.5 ampsThere seems to be some sort of threshold with the voltage. It is hot today so I am running the roof air. Voltage is 117 and wattage is 14xx. Charging is happening at 49 amps in float mode.I don't know the menus well at all.GordonThree wrote:Sounds like a programming issue, I'd recommend calling in to Magnum or whatever their new ownership calls them now.Do you have the Magnum BMK as well, or just the charging amp-meter the remote provides? I'm wondering if the actual amperage into your batteries is different than the guesstimate shown on the remote.Next question, how many amps were the solar panels contributing to the system?Last question, in the ARC menus, what do you have your charging mode voltage thresholds set at? Perhaps with the solar coming in and not much load, the Magnum's computer decided the batteries don't need aggressive charging based on the voltage.My ARC will not switch into Absorb until the load gets quite high, dropping the battery voltage, and Bulk comes in at an even lower voltage. I can look in my menus later today for you if you want to compare.In one of the menus, there is an option to force the batteries to charge, equalizer mode or something? I've never done it on my bank, I don't think AGM need an equalizer charge - maybe Mex has some words of wisdom on that subject...

an unusual charging problem | Good Sam Community

pianotuna
Nomad III
Sep 01, 2016
Well,

I don't have to worry about the Magnum not charging properly.

I got lucky and had the Magnum and the generator turned off as I was going to be gone for a while.

I came back to soot on the wall above the unit.

I've let out the magic blue smoke.
MEXICOWANDERER
Explorer
Sep 01, 2016
Yup, and hopefully the TVS and MOVs will provide that 10-30 ms buffer.

Wuwu! La Dentista is a real looker! Any distraction in a storm, they say...
pianotuna
Nomad III
Sep 01, 2016
Hi Mex,

I hope the tooth fairy will ease your pain.

I find that switching is fast enough on the Sola Basic that voltage jumps up before the air conditioner compressor motor makes a sound and before the fan has even started to turn. I was pleasantly surprised that was the case.

Obviously, the Sola cannot deal with millisecond voltage excursions, which is why I want to do some surge suppression.

MEXICOWANDERER wrote:
First of all let's trash some garbage information...

3. A weak point in stepped MEXICAN autoformer voltage control, is it takes time for the device to switch from one step to the next. Sudden line surges can raise (or lower) voltage by the percentage of boost (or sag) built into the transformer switching system. The switching has to have hysterisis to prevent stitching chattering.
MEXICOWANDERER
Explorer
Sep 01, 2016
First of all let's trash some garbage information...

1. Comision federal de Electricidad operates on a national standard of 127vac 60Hz and 254 Vac dos hilos and tres hilos (single and three phase). The only time they drop line voltage sans L0 neutral is when the customer provides their own transformer which regs demand to be a "Y" connection meaning 4 taps, one being L0.

2. An autoformer absolutely can raise or lower AC voltage values. But there is no true isolated secondary. The biggest fault of the autoformer versus a true 2 windings transformer is line ISOLATION. True isolation not only demands a 2 winding (not common leg connected) transformer, but an earth ground barrier to eliminate cross channel contamination. The isolation is expressed in db.

3. A weak point in stepped MEXICAN autoformer voltage control, is it takes time for the device to switch from one step to the next. Sudden line surges can raise (or lower) voltage by the percentage of boost (or sag) built into the transformer switching system. The switching has to have hysterisis to prevent stitching chattering.

4. Not only do I actually operate 3 buck boost autotransformers like Pianotuna's I own four Sola ferroresonant line regulators, the largest being 3.1 Kw, which has a secondary full 38 db isolation transformer. This is all being done on CFE power.

5. I have never experienced a prolong overvoltage condition with a Tor Rey autotransformer as fast acting fuses are mounted in the faceplate of the autotransformer and they will fail if the unit is over-amped.

6. I found it helpful to study line voltge output of the Tor-Rey and also the Sola units using a oscilloscope. The first 8 or so ms of step transition incurs a slightly warped waveform with no prominent spikes or sags.

7. Whenever a product promises "Automatic" anything, it means that other performance values can be affected as well. This "shotgun" approach of automation is one of the largest reasons I utterly shun products that attempt to think for me. Such products commonly incorporate the word "smart".

8. Oh goodie, after waiting two and a half weeks, today is the day I drive 155 miles for a root-canal. Tiny as it is, the compensation is to save the tooth and the bill is eqvt to $137.00 A bad point is epinephrine-free Novocaine is not available down here and my heart may not like this at all. And people wonder why some of my responses are so grumpy. Well so be it. If epinephrine raises my pulse to 400 I'll be the first to know.
pianotuna
Nomad III
Aug 31, 2016
Trust MrWizard to hit the nail on the head.

I've fine tuned the voltage drop needed. If I can keep at 120 then it behaves well, and the Yamaha can run at the slowest possible speed.

I wonder what the folks with Honda's where the voltage is 126 to 128 would do to drag the voltage down.
MrWizard
Moderator
Aug 31, 2016
Yes there is.. Fuel consumption
Turning on extra loads, to get the magnum happy, so it will charge properly
time2roll
Nomad
Aug 31, 2016
pianotuna wrote:
I did not wake up soon enough so solar has it at 12.6
Not sure if there is any real effect from the problem.
pianotuna
Nomad III
Aug 31, 2016
Hi Mr Wizard,

You may be right about the wave form being "too tall".

I did get it to charge in bulk yesterday with the roof air running. Charging rate was 102 amps in Absorb at 12.7 volts. I got in over an hour or more.

No word back from Magnum. They want me to test on 30 amp shore power. Of course it will work fine on that.
BFL13
Explorer II
Aug 31, 2016
If no scope, just tap it with your tuning fork. :)
MrWizard
Moderator
Aug 31, 2016
Don
Have any friends with an oscilloscope
You need to observe the wave form before connecting the magnum
With magnum misbehaving
With added load