AM radio noise from SB2000E

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Comments

  • BB.BB. Super Moderators, Administrators Posts: 30,226 admin
    Re: AM radio noise from SB2000E

    There is a long thread elsewhere on this board--but the basics are that AC current is not a continuous current flow, but is instead changing polarity and stopping every 1/2 cycle and it is quite a bit more difficult to sustain a continuous arc... DC current is continuous flow in one direction and very easy to sustain quite large arcs (hi-frequency welding systems are a different animal all together).

    So, if you look at switches (and circuit breakers, fuses, etc.), you will see on many of them both an AC and a DC rating, and the DC ratings are almost always quite a bit less in current and voltage ratings. DC switches are, generally physically larger to move the contacts farther apart and withstand the inevitable arcing that will happen with DC switching under load. If you switch the circuit off when there is no load--then there is no damaging arcs either... So the AC voltage and current ratings are safe for DC in that case.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490mike95490 Solar Expert Posts: 8,667 ✭✭✭✭✭
    Re: AM radio noise from SB2000E
    jauguston wrote:
    Guys, I just had a thought that might cure my problem but it seems like it might be too easy so please tell me what would be wrong.

    As soon as the red charge indicator light goes out like when I pull under the RV cover or night comes the interference stops. What bad will happen if I put a switch on the + lead coming from the panels and just shut them off from the controller when we are traveling? On the road traveling is about the only time we listen to the radio so that would make DW happy.

    Jim

    While you travel, do you need to charge, to top off the batteries, or do you have a booster to have the 13.8V car alternator top off the deep cycles to the 14.8V they need ?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • jaugustonjauguston Registered Users Posts: 20
    Re: AM radio noise from SB2000E

    Mike,

    I don't know where you got those numbers but they sure don't apply to anything I am familiar with and I have been a mechanic for 40+ years. Automotive and truck charging systems typically are set a14.4 to 14.6v with some newer GM systems set at 15v.

    Jim
  • mike95490mike95490 Solar Expert Posts: 8,667 ✭✭✭✭✭
    Re: AM radio noise from SB2000E
    jauguston wrote:
    Mike,

    I don't know where you got those numbers but they sure don't apply to anything I am familiar with and I have been a mechanic for 40+ years. Automotive and truck charging systems typically are set a14.4 to 14.6v with some newer GM systems set at 15v.

    Jim

    My bad. Those #'s ere a WAG from the back of my skull - not from any manual. I know the standard car battery is charged at a lower voltage than deep cycle & AGM cells, and that a car alternator will leave the deep cycle & AGM cells chronically undercharged.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • jaugustonjauguston Registered Users Posts: 20
    Re: AM radio noise from SB2000E

    Mike,

    Also not true and not relevant to the topic.

    Jim
  • mike95490mike95490 Solar Expert Posts: 8,667 ✭✭✭✭✭
    Re: AM radio noise from SB2000E
    Mike,
    Also not true and not relevant to the topic.

    It otter be quite relevant! If the solar charger is going to be shut off while on the road, so the radio can be listened to, will be batteries be undercharged, if only charging via vehicle alternator.

    Hey - drive at night ! No sun,=no solar charge=no radio interference - and you get the AM skip stations too!
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • crewzercrewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: AM radio noise from SB2000E
    While you travel, do you need to charge, to top off the batteries, or do you have a booster to have the 13.8V car alternator top off the deep cycles to the 14.8V they need ?
    Automotive and truck charging systems typically are set a14.4 to 14.6v with some newer GM systems set at 15v.

    It appears to be true that the alternator output voltages have improved over the past few years. For example, the charging voltage measured on the terminals of my F-250 SD's starting battery, which is located near the alternator, measures ~14.4 V when the alternator is running but cold. I haven't tried it when hot..

    But, I never measured such a voltage at the battery terminals on my old camper. Allowing for voltage drops due to various loads, wire resistance, fuses, and dirty connectors, I never saw the house batteries reach any better than 13.8 V.

    The real concern is the voltage (ref 77 F) as measured at the house battery terminals, not at or near the alternator. Unless the voltage reaches ~14.4 V (typical "marine" hybrid deep-cycle flooded-cell battery) to ~14.8 V (true deep-cycle flooded-cell models such as Trojans) for several hours, then the house batteries aren't getting a full absorption charge. For periodic equalization, these batteries require ~15.5 V.

    HTH,
    Jim / crewzer
  • jaugustonjauguston Registered Users Posts: 20
    Re: AM radio noise from SB2000E

    Jim,

    The term "true deep cycle battery" now adays means pretty much what ever the battery marketer says it is. In the past the accepted way to be sure you were getting a "true deep cycle battery" was the fact that they did not have a CCA rating. I am speaking here of 12v batteries. Today I doubt you will find a 12v "deep cycle" battery that does not have a CCA rating. I have a Trojan product brochure here in my hand and ALL their 12v batteries have a CCA rating. They call them things like "Marine /Deep Cycle or other things but they all have a CCA rating. Generally the batteries they call "deep cycle will have a bigger reserve number and a smaller CCA number for a particular Amp Hour size battery. The "equalization voltage" thing is a non-issue and it is generally accepted that it is a unproven and unneeded procedure.

    AGM batteries are not something I have a lot of experience with as they have no real place in RV use. Their high cost per amp hour per pound make them a poor choice for most applications. Their only seeming advantage is the ability to absorb a lot of charge amps quickly but most don't have the high output chargers to take advantage of that feature. Most folks I talk to that have AGM batteries are really proud they have them as if it was some sort of a status symbol to have very expensive batteries :-D

    This subject gets beat to death constantly on RV.Net. The accepted best all around batteries for a RV house installation if the height is available (they are tall) is the 6v golf cart battery and they do not have a CCA. The Interstate 2200 and the Trojan T-105 are the most common. My personal choice is four Interstate 2200 6v wired for 12v.

    It is generally accepted that in a RV application getting a full absorption charge is not the goal. That last 10-15% of charge comes pretty slow so working the batteries from about 85-90% of charge down to 50% charge (12.2v rested) is most practical. Your mileage may vary (-:

    Jim
  • System2System2 Posts: 6,290 admin
    Re: AM radio noise from SB2000E

    ^ I'm getting some popcorn, this should be good!

  • crewzercrewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: AM radio noise from SB2000E

    Jim,

    Like with most marketing activities, there’s no doubt a certain amount of “puffery” associated with battery specs and nomenclature. And, as you suggest, there are plenty of deep-cycle batteries out that include CCA specs, something that used to be taboo.

    However, it seems to me that adding a CCA spec to a deep-cycle battery doesn’t mean that it’s no longer a deep-cycle battery. It’s just a spec for a particular battery’s capability under CCA test conditions (# amps a lead-acid battery at 0ºF can deliver for 30 seconds and maintain at least 1.2 vpc).

    In general, it’s my understanding that “true” deep cycle batteries are ones that are designed with relatively dense plates designed to sustain many cycles of “deep” discharge and subsequent recharge. SLI batteries (starting, lighting and ignition), on the other hand, are designed with relatively porous plates (lots of acid-to-lead contact area) to facilitate short bursts of high current required, for example, to start an automotive engine. SLI batteries typically do not hold up well under deep discharge and recharge cycles due to related mechanical stresses.

    And, CCA specs or not, Trojan's "daily" (absorb stage) charging specs for their 12 V flooded-cell deep-cycle batteries is 14.8 V at 80 F. See: http://www.trojanbattery.com/Tech-Support/BatteryMaintenance/Charging.aspx
    The "equalization voltage" thing is a non-issue and it is generally accepted that it is a unproven and unneeded procedure.

    Yikes! That’s the first time I’ve ever seen a statement like that! If that’s really your view on this topic, then I doubt we’ll get far trying to discuss it. Otherwise, test reports from Sandia Labs, and maintenance procedures from well-respected flooded-cell battery manufacturers such as Interstate, Trojan, and Rolls/Surrette provide substantially different perspectives.

    See: http://www.sandia.gov/pv/docs/battery1.htm
    And: http://www.interstatebatteries.com/www_2001/content/faqs/tech_talk/terms/e.htm
    And: http://www.trojanbattery.com/Tech-Support/BatteryMaintenance/Equalizing.aspx
    And: http://www.rollsbattery.com/Bulletins/605.htm

    But, I’m always open to objective discussion and perspectives, and I’d love to read any technical reports on the fallacies of deep-cycle flooded-cell lead-acid battery equalization.

    Regarding AGM batteries, I agree that they seem to be costly – on the surface, anyway. However, their higher recharge efficiency (~90% Wh out / Wh in) vs. that of flooded-cell batteries (~80% Wh out / Wh in) means that a smaller (and cheaper) PV array is required to meet the same energy requirement. And, they're virtually maintenance free.

    For example, my four size 4D AGM batteries cost $220 each, which I suspect was about a 50% unit premium ($73) over regular ol’ flooded-cell models. So, I paid an “extra” $292 for my batteries. But, their better efficiency means that my system performs as if I had an ~815 W (STC) rated array instead of the 725 W system I actually have.

    Adding an ~90 W PV module to my system would have cost ~$431 (a Kyocera 85) – more than the extra $292 I spent on my batteries, and I’d still have all of that nasty maintenance work to do. :wink:

    T-105’s are a good and cost effective choice for RV batteries, especially if they aren’t well maintained and they have to be replaced fairly often. But, the practices described in Trojan’s on-line maintenance manual will definitely help extend their useful life. You probably even have phred Tinseth on your side on this one. See: http://www.phrannie.org/sources.html#4H . But, he personally prefers AGM batteries, and has had good (and cost-effective) luck with gels as well.

    I agree that the last 10% to 15% of charge comes pretty slow – that’s a well understood phenomenon. Considering the cost of fuel to run a generator, limited recharge may actually be practical thing to do. But, this type of repeat deficit recharging will reduce both a battery’s useful capacity (Ah) as well as its useful life (cycles).

    But, this is where a PV system can really “shine”. 8) Once a house battery bank is recharged to ~85% to 90% SOC (roughly the bulk- to absorb stage transition), a well balanced PV system can quietly take over and quietly finish fully charging the battery bank.

    In the end, it seems to me that we’re looking at battery charging from two different perspectives. If the “RV strategy” is to indifferently recharge and/or maintain an oversized battery bank to a “good-enough” level, and then replace it after every couple of years of irregular use, then the approach you’ve described has worked well enough for many people for many years without them having to become "battery gurus", and (seriously), it's probably saved many from unfortunate accidents by not working around sulfuric acid.

    In the off-grid world, the preferred practice, as best I can tell, is to maintain the batteries in general accordance with the manufacturers’ recommended protocols, including regular full recharges, and, for flooded-cell batteries, periodic equalization stages. Users can expect many years (thousands of cycles) of dependable battery operation this way.

    To wrap up, I doubt that you'll find much support for the "RV" style of battery maintenance on this forum, from battery manufacturers, or from multi-stage charger/controller manufacturers. Similarly, I didn't find much interest in my "off-grid" style over on a couple of RV boards, and that's why I left 'em.

    Regards,
    Jim / crewzer
  • jaugustonjauguston Registered Users Posts: 20
    Re: AM radio noise from SB2000E

    Jim,

    I certainly don't want to get into a pi**ing contest here. My point was today it is difficult to sort through the marketing BS to know if what you are buying that says it is a "deep cycle" battery is in fact what we believe to be a genuine deep cycle.

    No question the RV application is not the same as the off grid app. The common thread here is we both use solar to improve our living conditions.

    The golf cart batteries actually do quite well in the RV environment. It is not unusual to get 6-8 years out of them under conditions that are not anywhere near as pampered as they would be in a off grid application. The key to long battery life in a RV is a good three stage smart converter that will drop to around 13.2v when things are charged, that being below the gassing voltage of a wet cell, thus no water use. Most RV batteries are killed parked in storage with the shore power plugged in and the converter cooking the water out of them with too high a charge voltage.

    Jim

    Jim
  • crewzercrewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: AM radio noise from SB2000E

    Jim,

    You'll find that we voluntarily maintain a pretty civil forum here. Pi**ing contests are almost unheard of, although we've been close a few times. I should know... I was involved in one or two. :oops: However, objective technical discussion is encouraged, in my view.
    The key to long battery life in a RV is a good three stage smart converter that will drop to around 13.2v when things are charged, that being below the gassing voltage of a wet cell, thus no water use.

    I'd generally agree with that statement. Examples of such a charger are the Xantrex TC-20+ and the Iota DLS converters with the optional IQ smart controller. However, for the charger to drop to ~13.2 V (the float stage), it normally has to have completed that pesky absorb stage, where the last 10% to 15% of a full recharge occurs. So, absorption is indeed an important stage, and, if regularly applied, it can greatly reduce the need for equalization charges.

    And, you're unfortunately correct about one of the leading killers of RV batteries. Next to sulfation (due to no recharging, poor recharging, and/or self-discharge), "over charging" seems to be high on the list.

    Regards, and happy Memorial Day weekend!
    Jim / crewzer
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: AM radio noise from SB2000E

    very well said crewzer.
    jauguston,
    getting back to the subject of the interference, besides turning off the solar power, did you make any progress at reducing the rfi?(Radio Frequency Interference)

    hey ba, did you finish your popcorn? if not pass some over.
  • jaugustonjauguston Registered Users Posts: 20
    Re: AM radio noise from SB2000E

    Niel,

    Turning off the panels will accomplish what I wanted, a quiet no interference radio for DW while on the road. I don't plan to do anything further.

    The converters I am using, I have two, are WFCO 55a from bestconverters.com. They have three stages, 13.6 - 14.4, and 13.2. I have one of the converters powered directly from the gen set so it is only used when boondocking. With the two 130w Kyocera panels we won't need them too much anymore :-D We just spent a week in Eastern Washington and only ran the generator for the microwave and we boondocked the whole time.

    Jim
  • jaugustonjauguston Registered Users Posts: 20
    Re: AM radio noise from SB2000E

    Just a quick update. With a switch in the line from panels to the SB2000E the radio noise issue is no more.

    I couldn't be happier with the performance of the two Kyocera 130w panels and the SB2000E controller. We have been on two one week outings since we installed the system with no shore power either time and we have not changed our power use habits. We use the inverter in the AM for the coffee maker and the wife's latte maker, TV and Direct TV in the evening, some furnace run time at night, laptop use, cell phone chargers, etc, etc. The only thing we have used the generator for is the microwave. My existing digital volt meter on the battery bank is usually at 14.10 to 14.20 by mid afternoon and it agrees with the one on the SB2000E.

    Jim
  • crewzercrewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: AM radio noise from SB2000E

    8-)
  • mike95490mike95490 Solar Expert Posts: 8,667 ✭✭✭✭✭
    Re: AM radio noise from SB2000E
    jauguston wrote:
    The converters I am using, I have two, are WFCO 55a from bestconverters.com. They have three stages, 13.6 - 14.4, and 13.2. I have one of the converters powered directly from the gen set so it is only used when boondocking.

    Does this mean when you fire up the gen in the AM for the microwave, you also get a quick charge into the batteries from the generator ?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • System2System2 Posts: 6,290 admin
    Re: AM radio noise from SB2000E

    That's great! Now you don't have to sqaunder that great charging opportunity while on the move.

    Some of my best solar charging is while going down the road in my rv. I have even permanently disconnected my tow vehicle charge line to the trailer and just let the solar panels, and the MX-60, handle the charging - which is usually complete (Bulk and Absorb), by 1 p.m.

    The Trojan 6 Volts are great if you have the vented space for them and do not mind the watering and cleaning.  IMO AGM's are, by far, the best for RV'ing. First, most RV's have very limited vented battery storage capacity. With AGM's you can put them in closed compartments close-by the inverter/charger and solar controller.  Plus, like Jim has mentioned, they charge up much faster so you get the batteries to "Float" stage quicker than with flooded cell lead acids: Less smelly, noisy generator usage when you (and your neighbors) could be enjoying the great outdoors.

    Irrespective of the type of battery, it's good to invest in a 3 stage charger and to learn how to monitor it's performance.

    The RV'ers on the sites that I frequent are very savy about solar power and battery maintenance. But these are mostly the fulltimers who rely on their solar and battery banks 24/7 year-round.
  • jaugustonjauguston Registered Users Posts: 20
    Re: AM radio noise from SB2000E

    Phil,

    I am not a believer in AGM in a RV. The cost per pound per dollar per amp/hour capacity doesn't add up. The ability to absorb a higher charge rate than a flooded lead-acid battery advantage is lost in most RV's due to the limited converter output that is common. The only remaining advantage of low maintainance comes at a very high price. Most of the RV'er I have talked to that had AGM batteries seemed to have the attitude that they must be good because they spent a lot of money for them, like it is a status symbol to have very expensive batteries :-D
  • System2System2 Posts: 6,290 admin
    Re: AM radio noise from SB2000E

    I just set-up my retirement RV 5th wheel after trading in a travel trailer that we used for the past 10 years.  We like to boondock and hate using a generator. Previously, we usually used only about 50 Amp Hours per day, even when the temps got down to the 30's at night. But this was basic operation, no Television/DVD or computer or microwave, etc.

    Now, since this new 5th wheel will be our retirement rig, and we will be spending far more time in it, we want more power/luxuries/entertainment. So we now have solar power (6 each, Kyocerra 130's) and a Magnum Pure Sine 2,000 Watt inverter/charger (100 Amp). We are set-up to consume 150 Amp Hours/Day for 3 days w/o sun or generator charging, w/o going below 50% discharge.  Pursuant to this  we have 4, 4D size AGM's (800 Amp Hours) in my front storage compartment with my inverter/charger and solar controller about 1 foot away.

    I would not have been able to place flooded lead acid batteries in this closed compartment, especially along with the electronics. Otherwise, I have only the stock vented battery compartment that holds only about 200 Amp Hours of batteries: Either 2 each group 27's or 2 each of the 6V Trojans.  I used that stock compartment for 2 group 27 AGM's (200 Amp Hours). These two are isolated from the large 800 AH "House" bank and are used solely as my "Chassis" batteries to operate the levelers and the slide outs. So, if something goes wrong with the house bank, we can still pull up stakes and get out of the woods, or, otherwise have spare emergency power. In total I have 1,000 Amp Hours of AGM's, all usually charged solely by solar using the Outback MX-60 with a remote temperature sensor and a Balmar Duo Charge (isolator/charger), also with a remote battery temp sensor. My inverter/charger also has a remote battery temp sensor as does my battery monitor.

    The main value to me of the higher/faster charge rate is that the batteries require less sun to get them fully recharged to float stage.  Anyone who knows batteries will tell you that it is critical to fully charge batteries at least 2x per week to prevent them from premature failure.

    The increased charging efficiency of AGM's may not be a critical factor for you if you camp in the desert or the mountains of AZ or Utah, etc. with plenty of sun.  However, we like to camp in the Redwoods on the soggy/foggy Northern CA Pacific Coast, both winter and summer. Therefore, we are lucky to get a few hours of sun per day.

    Unless you know each individual's demands/power consumption, their means to safely stow batteries and their ability to recharge them, (like availability of sunlight), your declaration that AGM's are not cost effective is groundless.  I assume you were joking that RV'ers buy AGM's just to have bragging rights that they have expensive batteries? If not then that's one of the more perverse things that I've heard in awhile. "Hey Sugar, come on over here and check out these AGM batteries!" I mean are folks usually impressed by others' batteries? I'll have to try that one...

    Finally, I agree that the Trojans offer the best bang for the buck, if there is a safe, vented place to stow them. For the capacity that I need to do my generator-free boondocking in the Pacific NW, and to quickly recharge in limited sunshine conditions, plus, the need to stow them in a closed compartment, the choice of AGM's was a no brainer.
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