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Old 06-25-2018, 04:00 PM   #201
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Magnum MMS Series 1012 issue with AC ripple voltage

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Originally Posted by Boxster1971 View Post
Unfortunately with either Magnum model OFF there is still a drain on the batteries. It is less than the search mode. I just checked my notes and past posts and this totally OFF drain is 0.3-0.4A as measured on my van since I have a shunt current meter for both the Magnum and Blue Sky solar controller. The power to keep the comm line between inverter and remote has to come from somewhere.

This parasitic drain is what drove both Airstream and Crestline Coach to add a 12VDC disconnect on the Magnum Inverter.

This issue is not limited to Interstates, but is aggravated because the Interstates only have a 160AH's of coach batteries and another parasitic drain from the entertainment system. That is less battery capacity than recommended by Magnum. The new 2019 Interstates will now have double that with four batteries and 320AH capacity. Progress.
Thanks for giving us the straight scoop on this Mike.

I never bothered to use my Fluke to measure the current draw with our MS2000 switched "OFF". I figured off meant off, and the power for the remote was negligible -- it never occurred to me that the current draw when OFF would be as high as 0.3 to 0.4 amps, almost as high as when ON and "searching". Especially since the specs -- while they do list "searching" and "inverting" (with no load) power consumption -- do not mention any power consumption when "OFF".

Sigh...

Now I'm tempted to add a battery disconnect switch but if were to do so it's all but guaranteed we would forget we'd opened it and plug into shore/gen power with the batteries disconnected. So I guess I'll leave it as-is.

Speaking of parasitic drains, the newer Views/Navions also have that problem. WGO reduced the size of the LP tank (13 gal vs 18 gal) and relocated it further under the chassis, so the manual shutoff valve cannot easily be reached. That in turn necessitated a solenoid actuated propane valve that pulls almost 1 amp, 24/7, as long as the propane is turned on -- which is usually the case, because if nothing else the fridge needs propane. For people that dry camp and/or boondock this is a serious issue. Even if they have upgraded to 220Ah GC batteries, that's only 110Ah available (~50% of capacity). The LP valve alone is using 24Ah every day. That's about 22% of usable capacity -- for a valve that would not be necessary had WGO kept the old design.

That's one of several reasons I'm glad we have a 2009 model, and it might make AI owners feel a little better about the draw from the entertainment system.

<Columbo mode again>:

So, if I understand correctly, in normal operation the batteries are always connected to the inverter:

1) When shore/genset power is present -- to filter any AC ripple and prevent the problem Alex and Crestline had; and so that the battery charger can keep the batteries topped off.

2) When shore/genset power is not available -- so that the inverter can supply 120Vac to any loads connected to the 3 outlets.

Under what conditions are the batteries disconnected? Is it primarily just for storage when shore power is not available?

The disconnect is controlled automatically, correct? If so, then how is it possible to have the batteries disconnected while the inverter has 120V on its AC input? Can the disconnect be opened manually, and once that has been done, only be closed manually -- like a manual override?

It's good that AS is doubling the size of the battery bank. 320Ah should be plenty for the MMS1012.

Unfortunately, we only have space (and OCCC) for 2 GC batteries. I did purchase "oversize" (taller) Crown GC batts, 260Ah each, but that's still less than Magnum recommends for loads greater than 1,000W. They say 200Ah is the minimum for loads <1KW, but >400Ah is recommended for loads >1KW.

I'm more concerned about that now after reading Pat's post (above) about DC ripple.

Too bad lithium batteries are still so expensive.
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Old 06-25-2018, 04:16 PM   #202
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Thanks for giving us the straight scoop on this Mike....

<Columbo mode again>: ...

Under what conditions are the batteries disconnected? Is it primarily just for storage when shore power is not available?

The disconnect is controlled automatically, correct? If so, then how is it possible to have the batteries disconnected while the inverter has 120V on its AC input? Can the disconnect be opened manually, and once that has been done, only be closed manually -- like a manual override? ...
Yes - disconnect would be used when storing or extended parking with no shore power.

Disconnect is manually engaged by user. There is a switch that energizes the two motor driven switches. One for the 12VDC distribution panel and one for the inverter/charger. On the 2018 Interstate Airstream added the ACE circuit to prevent disconnecting the inverter/charger when 120VAC is feeding the inverter/charger. The two disconnect switched can also be operated manually overriding the motor function on switchs.
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Old 06-25-2018, 04:32 PM   #203
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Good evening folks. Sorry to be MIA since early a.m. yesterday. Pls. bear with me as I try to catch up on some posts that I need to reply to. Was busy after I picked up AI from dealer, getting her ready for trip to So Cal and Malibu for 4th of July.

BOOM23 - not sure if I can make time to stay in Huntington Beach. Will see

Quick update:
1. New Magnum inverter, smoke detector, new CO detector. Unit has been "burning in" (hate that phrase but an industry norm that I have used before) at dealer's service bay & outside for over a week under load & stresses of Las Vegas heatwave.

2. Jackson Center ok'ed the pickup Friday afternoon.

3. Jackson Center assured me there will be a thorough investigation starting this week. Magnum tech people are supposedly to meet with them early this week. My inverter was overnighted to Jackson Center.

4. As for my strategy:
- keeping the cushion off the top of electrical compartment.
- keeping an exhaust fan over the protective grill to remove as much heat.
- designing a separate active exhaust enclosure that will be imbedded in the seat cushion.
- enclosure will contain multiple exhaust fans, goal is >59 CFM airflow.
- will enlarge the grill opening to be as large as possible.

Just to give an idea of how hot it can get here, when I picked up unit around 3pm, AI was only sitting in sun for couple hours. Outside temp 114 degF, inside was 117 degF, parking lot ashphalt was 152 degF. Top of new Magnum is the same 117 degF using Snap-On multi-laser infrared thermometer at 1" reading (remember, the seat cushion is not installed yet). May test with seat cushion on top, but debating if I even want to take that risk? Maybe after my trip.
Hi Alex,

Glad to hear you got your rig back!

WRT #1 above, was the 1012 in "inverter mode" or "AC pass-thru/Battery charger mode" at the dealer?

Did they have the seat cushion in place?

I'm sure I speak for many people when I say I'm very anxious to get the results of the investigation.

Your strategy sounds good. Anything you can do to keep the inverter/charger as cool as possible will be helpful.

In your other post you said you had not been able to find any diagrams for the MMS1012 -- the manual can be found here:
http://www.magnum-dimensions.com/sit...Series_Web.pdf

The specs on p.39 show the operating temp range from below 0*F to 140*F. While it does get smokin' hot where you are, the normal temp inside your AI when you are using it should be much less than ambient. It should be fine, esp with the cushion up/removed.

Earlier in this thread, when we were not aware that the damage was caused by AC ripple current when the batteries are disconnected, I was looking for more typical reasons why the inverter might fail. Upon seeing the AS installation, which seems to disregard many of Magnums recommendations, I focused on that as a potential cause

Now that the cause is known, I still think it is a good idea to mount the 1012 securely and give it plenty of ventilation, but it may not be as critical as we originally thought.

You might consider monitoring the temp in the inverter compartment so you have an idea how much of an issue you have with heat, before you get into a lot of mods.
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Old 06-25-2018, 05:03 PM   #204
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Yes - disconnect would be used when storing or extended parking with no shore power.

Disconnect is manually engaged by user. There is a switch that energizes the two motor driven switches. One for the 12VDC distribution panel and one for the inverter/charger. On the 2018 Interstate Airstream added the ACE circuit to prevent disconnecting the inverter/charger when 120VAC is feeding the inverter/charger. The two disconnect switched can also be operated manually overriding the motor function on switchs.
My first thought is that all of this is a lot to go through, all because an inverter cannot be shut off completely.

I understand that the disconnect would be used when storing or extended parking with no shore power. That makes perfect sense.

It sounds as though it is as I suspected -- that "the disconnect can be opened manually, and once that has been done, it can only be closed manually -- like a manual override." Is that the case? Is that how an owner ends up with 120Aac connected to the inverter and the batteries disconnected?

I see a SPST switch labeled "M4d-2" (which is the nomenclature for the inverter main disc. switch) -- is that the switch you referred to that operates both motor driven switches -- the one for the 12VDC distribution panel and the other one for the inverter/charger?

When storing the AI, why not use that switch to operate both disconnects, rather than manually operating the inverter disconnect? AS should emphasize that procedure (assuming it is possible).

IOW, unless the inverter disconnect *must* be manually operated, it seems best to use the motor driven function.

Again, I have a View, not an AI. There's a good possibility that I don't completely understand how the ACE circuit works, but ideally the owner should not have to think about it. If the disconnects are open and they plug in to shore/gen power, they should automatically close. Is that how it works?
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Old 06-25-2018, 05:34 PM   #205
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The two switches are the same or similar to the switches in this West Marine link.
https://www.westmarine.com/buy/bep-m...es--P014981633

They have ON/OFF/AUTO positions and must be in AUTO to enable the remote activation of the motorized functions.
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Old 06-25-2018, 06:06 PM   #206
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Originally Posted by Boxster1971 View Post
The two switches are the same or similar to the switches in this West Marine link.
https://www.westmarine.com/buy/bep-m...es--P014981633

They have ON/OFF/AUTO positions and must be in AUTO to enable the remote activation of the motorized functions.
Thank you Mike, your posts have been very helpful!

That's what I was thinking, based on your description.

Question:

With the ACE circuit and disconnects operating as designed by AS (no faults), can you think of any circumstance that would require an AI owner to operate the inverter disconnect switch manually?
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Old 06-25-2018, 08:08 PM   #207
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Quote:
Originally Posted by sajohnson View Post
Glad to hear you got your rig back!

WRT #1 above, was the 1012 in "inverter mode" or "AC pass-thru/Battery charger mode" at the dealer?

Did they have the seat cushion in place?

I'm sure I speak for many people when I say I'm very anxious to get the results of the investigation.

Your strategy sounds good. Anything you can do to keep the inverter/charger as cool as possible will be helpful.

In your other post you said you had not been able to find any diagrams for the MMS1012 -- the manual can be found here:
http://www.magnum-dimensions.com/sit...Series_Web.pdf

The specs on p.39 show the operating temp range from below 0*F to 140*F. While it does get smokin' hot where you are, the normal temp inside your AI when you are using it should be much less than ambient. It should be fine, esp with the cushion up/removed.

Upon seeing the AS installation, which seems to disregard many of Magnums recommendations, I focused on that as a potential cause

Now that the cause is known, I still think it is a good idea to mount the 1012 securely and give it plenty of ventilation, but it may not be as critical as we originally thought.

You might consider monitoring the temp in the inverter compartment so you have an idea how much of an issue you have with heat, before you get into a lot of mods.
SAJOHNSON - At the dealer's they were testing the inverter under varying conditions (inside, outside), maximum loading, but as to how long & what percentage of time spent in inverter vs. pass-thru vs. battery charge, no idea whatsoever. House was running 24hrs. for at least 5 days. I just told them all modes better be tested since I gave them an entire week just for testing purposes. I have no reason to suspect they didn't do so, all modes test just fine with new inverter. If they did not test a mode, I did at the dealer's lot before driving home. Even ran generator, VB Air, water pump, etc. even E&P Hydraulics, macerator, etc. while still at dealer. I was there 2x longer than the PDI

Yes, I have that manual (paper & pdf). That is the User Manual, dealing mostly with operational & external install stuff. Was looking for one that had some schematics diagrams, even at the block diagram level showing the inner workings, but can't find any. Something similar to the AI Owner's Manual section 9 diagams.

Yes, I see page 39 specs. But way before that, page 9 states:

"Cool – The inverter should be protected from direct exposure to the
sun or any equipment that produces extreme heat. The ambient air
temperature should be between 32°F (0°C) and 104°F (40°C)
; keep
in mind that the inverter’s output specifications are rated at 77°F
(25°C), so the cooler the better within this range."

So, as you may surmise, I have pointed them to that as they have stated it as a "requirement". So even if 140°F is truly it's max operating temp, it can not reach it's stated output above 77°F. They do not specify where the max operating temp is measured at (even though it is listed under "Environmental Specifications"). I would venture to say the 140°F is measured inside the casing. If it can not reach it's stated output due to high ambient temp, it will still try to keep reaching that output, which leads to more rise in internal temp, which should eventually lead to an overtemp shutdown (if the shutdown circuitry works) to prevent a mini-China syndrome meltdown scenario (which is what happened in this case). The Magnum did meltdown and if left on it's own, would've have completely burned down. No safeguard turned it off, I had to manually shut it down in the field. Dealer foreman had to shut it down in the shop.

To date, I have not & am not planning to do any electrical mods during the entire warranty period (unless approved by AS). Actually very glad I have resisted the urge to do so. I am always hesitant of doing electrical mods during warranty periods. Had I done even the slightest mod to that compartment, they would've had found some reason to void my warranty. Any compartment airflow mods that I do during the warranty period will have to be expressedly approved by Airstream. Even not putting back the cushion has been approved (at least as a temporary measure until they figure out what happened).

I am monitoring temps with various methods, just like one would a fridge. And physical measurements are done using one of the best infrared laser thermometers (that I trust) my Fluke 62 IR Max Plus with a calibration certificate. Dealer uses the Snap-On version (which I also like) but electronics & computer engineers like me grew up with Flukes, so there ya go



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With the ACE circuit and disconnects operating as designed by AS (no faults), can you think of any circumstance that would require an AI owner to operate the inverter disconnect switch manually?
Simple answer, NO. A little less simple, it is not easily accessible. Need to remove mesh grill at minimum, and/or also remove bottom cushion to make grill removal easier. Doing so means you are planning to do something major electrical work, hence disconnecting everything.
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Old 06-25-2018, 08:28 PM   #208
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It sounds as though it is as I suspected -- that "the disconnect can be opened manually, and once that has been done, it can only be closed manually -- like a manual override." Is that the case? Is that how an owner ends up with 120Aac connected to the inverter and the batteries disconnected?
SAJOHNSON - I knew I forgot something. The 2 big red knobs are not just manual disconnects. Based on my understanding of how these switches work (I have not tested all scenarios & combo permutations of both switches in relation to SPST switch by the sliding door) - While they do the "manual disconnect" function they can also force a "manual connect" function. So in that regard, it is probably best to call them "manual override switches". They would prevent accidental turning on or turning off the house batteries. Here again, AS does us a dis-service by not properly or at least carefully wording the terms they use to describe their switch functions.

Examples of forced overrides:
- In storage, you may want to have the batts manually disabled with no possible way of accidentally hitting the SPST switch & leaving the rig with batts connected
- Conversely, while camped, you may want to force the batts to always be connected so that even if you accidentally hit the SPST switch, you don't accidentally cut-off power to your Samsung big screen during SuperBowl XVXVX with score tied at 77-77 with 7 secs. to go on 4th down w/ Las Vegas Raiders on their own 7 yard line. I just had to make that plug even though it is still 2 yrs. down the line Had to find a way to get at least 3x 7's in there, did good with 6x!
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Old 06-25-2018, 09:21 PM   #209
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Hi Alex,

You're absolutely correct about high temps negatively affecting max. output. Needless to say, the range I quoted above (~0*F > 140*F) is merely the temp range over which the inverter will operate -- it is far from optimal. You had mentioned that the case temp was 117*F which seems close to worst case for a non-operating temp. That got me curious about the max operating temp, so I checked those specs. Chances are no one is going to be kicking back watching some TV in triple digit temps anyway.

The reason I asked what mode the 1012 was in at the dealer was because of your (very legitimate) concerns about heat. If the dealer left the inverter in pass-thru/charger mode, that would generate very little heat (assuming the batteries are charged) -- so that would not be much of test of a thermal stress test. What made me think they might have not used inverter mode was your mention of them running the A/C continuously.

OTOH, if they periodically had it in inverter mode, running (say) an electric heater on low (ours are 900W on low), discharging the batteries 30-40%, then reconnecting shore power and letting the charger go thru its paces (bulk/absorption/float) that would be a good test.

That said, it sounds like you did a bunch of testing yourself, and since you plan to make those mods to keep it cooler, it should be fine.

The Magnum MS2000 owner's manual has good block diagrams on pages: 34; 35; 36;39; 44; and 45 -- as well as numerous wiring diagrams for a variety of installations:
http://www.magnum-dimensions.com/sit...Series_Web.pdf

Between looking at it and the AI owner's manual (that also includes schematics) I was thinking the MMS1012 manual had some block diagrams as well. I'm surprised that it doesn't, that's too bad.

Regarding the inverter disconnect switch, near as I can tell from what has been posted, your 1012 (and those reported by Crestline) went into meltdown mode due to being connected to 120Vac while the batteries were disconnected. In your case, how did the batteries become disconnected? Did ACE circuit fail? Is the motorized portion of the disconnect faulty? Just curious.

If the disconnect switch were more easily accessible, I might think someone may have turned it off manually. Apparently that's what happened with the Crestline ambulances.

I guess the "AC ripple" cause of failure is still just a theory at this point though, right?

In any case, sounds like you're good to go for your trip!
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Old 06-25-2018, 10:14 PM   #210
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As an aside guys, there is no such thing as "AC ripple." There is DC ripple but not AC. So the explanation given to us by Magnum or that recall notice is bogus.

I am not sure how the transfer function is implemented in Magnum. If it is with SCR/Triacs then not having the control circuit powered may be a problem. If it is relay, then I don't know why there would be any issue.
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Old 06-25-2018, 11:21 PM   #211
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Chances are no one is going to be kicking back watching some TV in triple digit temps anyway.

What made me think they might have not used inverter mode was your mention of them running the A/C continuously.

and letting the charger go thru its paces (bulk/absorption/float) that would be a good test.

That said, it sounds like you did a bunch of testing yourself, and since you plan to make those mods to keep it cooler, it should be fine.

Regarding the inverter disconnect switch, near as I can tell from what has been posted, your 1012 (and those reported by Crestline) went into meltdown mode due to being connected to 120Vac while the batteries were disconnected. In your case, how did the batteries become disconnected? Did ACE circuit fail? Is the motorized portion of the disconnect faulty? Just curious.

If the disconnect switch were more easily accessible, I might think someone may have turned it off manually. Apparently that's what happened with the Crestline ambulances.

I guess the "AC ripple" cause of failure is still just a theory at this point though, right?

In any case, sounds like you're good to go for your trip!
SAJOHNSON - I guess you have not been to Las Vegas when it is 117°F. We kick back & watch tv outside even with those temps My first trip for short test at Lake Mead National Recreation area, in late April we reached 100°F midday. That was when I discovered the A/C comm problem with Firefly.

There is a reason they used the A/C a lot during the testing. It was because using the A/C made the problem happen much, much faster. I saw it myself prior to bringing to dealer. Foreman who was doing all the work noticed the same. Don't ask me how that is. Many others here have scratched their head on that, I have, Jackson Center has. It just is. That is part of the post mortem they are doing, trying to figure out what the link is between the A/C & burning Magnum. Letting the charger go through it's paces is a good test but if that's not what causes the problem to surface, then it is not the best test.

Don't know where you got the info that my 1012 went into meltdown mode due to being connected to 120Vac while the batteries were disconnected. No one, not dealer, not AS, not Magnum has made any determination to that effect. They haven't even sat down yet for the post-mortem. That is supposed to start mid-week. Also, my Magnum smoked even when disconnected from shore power and generator running, but slower to get there. My batts were not disconnected, I would have known because I am the only one who knows where/what those are. Up until the meltdown, there is no legit reason to manually turn ON/OFF those disconnects (overrides). This is where my "No electrical mods" helps me. If this had happened to anyone of the folks here who had done major mods to the electricals, there is no denying those switches and batteries would have had to be disconnected. Or else, it is even a worse scenario. doing work without disconnecting everything. Then AS could've voided your warranty, even if it wasn't your fault.

Is ACE or both switches latching properly? None of those were implicated, to my knowledge, because only the Magnum inverter has been replaced (other than the 2 detectors also).

Yeah, hoping my diligence would pay off, with my own testing of the new setup. Will see.

Bottom Line - AS & Magnum are doing the analysis pow-wow this week. Do not know what info they will have for me or when. But as soon as I have more, I will report on whatever info I can provide.
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Old 06-26-2018, 05:59 AM   #212
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I am thankful that no one was injured. The camper can be fixed.
As you now know, children should never be left unattended anywhere - home, car, camper or elsewhere.
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Old 06-26-2018, 09:10 AM   #213
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Alex - good advice on not making mods while warranty is in force. My only thought on the A/C connection - the heavy load from A/C can drop the voltage going to Magnum in coach. Looking forward to hearing more about what Airstream and Magnum conclude.
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Old 06-27-2018, 12:50 AM   #214
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I am thankful that no one was injured. The camper can be fixed.
As you now know, children should never be left unattended anywhere - home, car, camper or elsewhere.
brick
BRICK - Thank you very much.

FYI - to clarify, grandson was NEVER unattended anytime. He was on one side of sliding door C/S captain's seat, I and members of family were on the other side of sliding door. I was literally only separated from him by the thickness of the slider door. Any closer and I would be sitting on his carseat. Slider door was partially closed, which means it is also partially open (50% closed/50% open)

Per my original post #1:
: : : :
3. Grandson was still asleep, strapped in his carseat.
4. Side slider door partially closed to keep A/C cold air in while allowing me to hear grandson.
5. Family was gathered around house, porch, and right next to side slider door.
: : : :
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Old 06-27-2018, 01:10 AM   #215
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My only thought on the A/C connection - the heavy load from A/C can drop the voltage going to Magnum in coach.
MIKE - I was thinking in that same line, though still unable to comprehend the direct connection. Of course still speculating here - that the dropping voltage to Magnum would cause a current increase to generate same ouptut, which cause more heat, which overtemps, etc. etc.

Eagerly awaiting more. None yet. Sigh!
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Old 06-27-2018, 08:23 AM   #216
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The ‘AC ripple’ didn’t make sense to me, I didn’t know what they meant by that.
But looking it up- I think it really just means AC is getting ‘into’ the DC. So instead of a steady, flat DC it changes voltage.

I spent many years as an electronics tech and often would be checking DC for ‘cleanliness’. Most of the equipment had very good filtering & regulation and the DC was very, very stable. It had to be or the discriminator wouldn’t work right, not to mention the oscillators.

That tells me the design of the Magnum is poor. Rather than making certain it would work correctly with no load- they are counting on the battery to be the capacitor and absorb voltage variations. Effective, but not when it is likely to be disconnected in use.

Of course, maybe most of these units are designed that way for size and cost reasons.
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Old 06-27-2018, 11:39 PM   #217
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But looking it up- I think it really just means AC is getting ‘into’ the DC. So instead of a steady, flat DC it changes voltage.

Effective, but not when it is likely to be disconnected in use.

Of course, maybe most of these units are designed that way for size and cost reasons.
Yes, I believe that is what AMIRM was saying also. Giving Magnum a little benefit of the doubt, they probably should've worded more accurately - "AC causing the DC to ripple" is more accurately descriptive of the issue. Because technically, there is really no such thing as AC or DC ripple. There is Ripple Voltage - which basically means you have some type of AC variation that sits on top of a DC voltage as it's reference voltage. It is the final job of the voltage regulator to clean up the Ripple Voltage to get your DC as flat-line as possible. The cheaper the unit, the less regulation, the more voltage fluctuations (ripple), the higher the heat, the shorter the life span of the component. We have no access to Magnum internal schematics, but it does seem that if batteries need to be always present as a load for Magnum to not meltdown from Ripple Voltage, they are using the batts as a capacitor (or more accurately it's final filter/regulator). Truly terrible design.

I would say cost is a big driving factor, yes.
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Old 06-28-2018, 06:32 AM   #218
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Historically, it was necessary to keep the batteries connected in Airstream trailers to smooth out the DC from the primitive converters used up unto about the 2000s. Only in recent years were the converters advanced enough to not require batteries constantly connected to act as filters.

Only difference, there were no battery disconnect switches on those trailers to cause problems.
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Old 06-30-2018, 11:14 PM   #219
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Only in recent years were the converters advanced enough to not require batteries constantly connected to act as filters.
JOHN - I wonder if my Magnum 1012 is advanced enough to do the job. I do realize it is a popular unit and many experienced users swear by the brand. But they are now hitting 0-for-2 in my book.

I was on my way to Zion National Park yesterday morning. 100 miles into the trip, the front Samsung turned off. It stopped inverting. Inverter led was off. Tried turning back on and just flashing led. Turned off chassis & house batts. Reset all ckt breakers. Same. Got to camp & plugged into shore power. NEW replacement Magnum will not pass shore power AC. It does charge house batts.

On the other hand, Zion is such a beautiful place, I will not let this crazy rv ruin it for my family, so we got the good old 20A orange extension cord to plug in the tv. But it is getting old - 4 multi-day trips with 4 trip-ending problems.

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Old 07-01-2018, 09:35 AM   #220
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But it is getting old - 4 multi-day trips with 4 trip-ending problems.
Very sorry to hear that you keep having problems Alex. I can't imagine how frustrating it must be to have this continue and to not have confidence in your coach. I've been fortunate and have had the opposite experience, and everything in my coach just works as intended with no dramas. Yes, I've had a few early failures (mainly my main cabin dimmer switch but that was diagnosed and replaced by me very early on), but since replacing my solar charge controller, I can honestly say my coach works better than new. I hope you get to the same point, and sooner rather than later.....

Safe travels.
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