Conext Battery Monitor : A serious threat to the Trimetric?

DMJ72DMJ72 Solar Expert Posts: 125 ✭✭
battery4.png

Data Sheet : http://solar.schneider-electric.com/wp-content/uploads/2014/07/DS20140718_ConextBatteryMonitor.pdf

Notable features :

  • Works as a standalone unit, No Schneider/Xantrex equipment needed
  • Communicates SOC, and other parameters to the Xanbus network
  • Data Logging with export of .csv files via USB
  • Mid-point detection of string imbalance
  • Comes with a shunt and a temperature probe



What do you folks think of this product?

Comments

  • ILFEILFE Solar Expert Posts: 364 ✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    I can't say about Schneider's, honestly. But, I personally like the Victron units.

    Victron Data Sheet (PDF)

    Attachment not found.


    I was going to buy one of these, until I got my Beta Kid. An offer for Beta Kid testers was a heavily discounted (or free?) Whizbang Jr. So, I went with it instead. I will probably still end up buying one, though, for my next solar project.
    Paul
  • mike95490mike95490 Solar Expert Posts: 8,821 ✭✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    somebody missed the boat. With larger systems (higher voltage) being planned, 66V is not enough. I'd have to use a DC-DC to power it, my system top voltage is 68V
    Including the shunt is a nice touch
    Electrical specifications
    Supply voltage 18 - 66 VDC

    Supply current (backlight off, logging-disabled)
    80 mA @ VIN=48 VDC, 150 mA @ VIN=24 VDC

    Input voltage range 0 - 70 VDC
    Input current range -9999 - +9999 A
    Battery capacity range 20 - 10, 000 Ah
    Operating temperature range -20 - +50°C
    Battery interface kit with shunt (included)
    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 ,

  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    mike95490 wrote: »
    somebody missed the boat. With larger systems (higher voltage) being planned, 66V is not enough. I'd have to use a DC-DC to power it, my system top voltage is 68V

    And I wonder why they decided to ignore the market for 12 volt system battery monitors.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • DMJ72DMJ72 Solar Expert Posts: 125 ✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    Its on NAWS now, pricey at $337!
  • SkiDoo55SkiDoo55 Solar Expert Posts: 414 ✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    Probably same reason that new XW+ inverter's are 48 VDC. What market is buying and approximate for the output power levels. It would have been easy to broaden the range. Definitely would have been nice to have lower price, but has mid point battery string monitoring and can do parallel strings, may be worth the price, time and being used by some of the knowledgable people on this site.
    GT3.8 w/4600W Trina 230W, TX5000 w/5000W ET-250W, XW4024 w/1500W ET-250W, 4 L16, 5500W Gen. (never had to use) Yet!!
  • HandyBobHandyBob Banned Posts: 31
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    I know the thread is old and I am not supposed to be bashing, but I am entitled to my hard earned opinions. The first thing I would say is Schneider? Seriously? I don't trust them to do anything right. They are even managing to screw up Square D..... I know how it sounds but I have a lot of experience. Square D was my favorite distribution and motor controls manufacturer back in the 1970's and 80's when I was in electrical consulting. They used to be wonderful. When I needed to do anything special in motor controls, I called Square D. Believe me, they are changing and it's not for the better. Go buy a Square D air conditioner disconnect and open the box. They used to make a very good one. Now they buy the crappy Eaton one and put their part number on the outside of the box. This is only the beginning. If you want to kick me off for saying the truth, I guess I'll have to say that I've been thrown out of nicer bars than this one.

    I may be in the position of having installed more Trimetrics than anyone else. Over the years I have installed 2020's, 2025's and now the 2030. I even own a prototype that nobody ever heard of, a 2021. I have never seen a bad one. Not one, never. They simply work. There is a bit of a learning curve in getting one set up and as with anything, garbage in = garbage out, but I love the Trimetric. More than anything else I love the % of charge that can be left on & seen from across the room. Much easier for the average person to understand. The new 2030 has an interesting new thing; rPC, returned % of charge (how much over charging it sees vs how much energy was used.) This little thing may help to show that most people are wrong about what constitutes over charging. I certainly hope so. I love to see 115% and more, verifying that my batteries actually are being taken care of. When paired with the SC2030, it is the smartest charge controller available. Not MPPT and limited to 30 amps, but able to be programmed for any charging profile you want, using rPC as a basis for dropping to float. Nothing is better.

    This past summer I have been testing the new TM2030 and SC2030 pair, providing feed back to Ralph on little things I found that didn't look right and he has been continually making changes. Right now I have version #8 and I believe it to be perfected. I have never seen this kind of dedication to making things right in any business. If anybody wants to argue with this, give Ralph a phone call. Then try calling Schneider.

    Xantrex never bothered to answer the letter I sent them many years ago, all too typical, and this was after trying to get a person on the phone several times. The old Trace (Xantrex) meter was nothing but problems. Magnum argued with me about the problems I saw with their BMK. Don't take me wrong because I love Magnum's panels and inverters. MidNite and I have been going round & round with Classic programming and noisy fan issues for over a year. To say frustrating is putting it very mildly. I won't be trying any new MidNite computerized products until somebody else works out all of the bugs. Victron does have a good reputation. Nothing bad to say there, except that it sure looks like a Link clone to me.
  • BB.BB. Super Moderators, Administrators Posts: 30,642 admin
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    Bob,

    Personal experience and opinions are always welcomed here. Both positive and negative.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    HandyBob wrote: »
    The new 2030 has an interesting new thing; rPC, returned % of charge (how much over charging it sees vs how much energy was used.) This little thing may help to show that most people are wrong about what constitutes over charging. I certainly hope so. I love to see 115% and more, verifying that my batteries actually are being taken care of.

    Thanks so much for a post that just reeks of experience :D

    About the rPC .... doesn't that depend on charge rate? I was under the impression that rPC is a measure of charging efficiency. Lower charge rates (within limits) are more efficient.

    Also, what about temperature? Temperature affects battery internal resistance which affects charge efficiency, capacity, and Peukert factor. Does the 2030 take temperature into consideration? Does the 2030 use Peukert factor (of loads) to calculate SOC?

    IMO, the temperature issue is the greatest weakness in my 2020. I have to manually adjust downwards the battery capacity setting on my 2020 in the winter. Also, I have to continually figure out what the temperature adjusted absorb voltage is on my FM60 so that I can set the Trimetric's reset criteria to match.

    I can certainly understand Midnite's approach... when they get the programming done, their integrated system battery monitor won't have the temperature issues that I experience.

    OTOH, one of the things I like about my Trimetric's lack of integration with my controller is that the trimetric is an independent auditor of my system. If my Trimetric disagrees with my controller about when the battery is charged, I can investigate. (usually it's temperature).

    I worry that there is no way to know when a fully integrated system starts doing things wrong, if all you know is what the integrated system tells you.

    Maybe it would be a good idea for those with the TM2030 - SC2030 integrated system to get a 2020 to monitor it with :p

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    Nota Bene:

    Pushing battery SG above the manufacturer's recommended level for full charge is damaging to batteries. Don't do it.
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    Nota Bene:

    Pushing battery SG above the manufacturer's recommended level for full charge is damaging to batteries. Don't do it.

    I don't understand how it is eve possible to push SG above the original SG.

    When the battery is filled with electrolyte (at whatever SG) isn't all the sulfur in solution? How can the SG go higher? Where does the sulfur come from to allow the SG to go above the original SG?

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    vtmaps wrote: »
    I don't understand how it is eve possible to push SG above the original SG.

    When the battery is filled with electrolyte (at whatever SG) isn't all the sulfur in solution? How can the SG go higher? Where does the sulfur come from to allow the SG to go above the original SG?

    --vtMaps

    Oh it's simple: water loss increases the percentage of sulphuric acid in the electrolyte which raises the SG.

    It also stresses the plates and possibly exposes them leading to instant death.

    But if you don't care how long your batteries last the higher acid concentration will effecitvely increase their capacity (while shortening their lifespan).

    If the maker say the battery has 'X' Amp hours at an SG of 1.2** then that's what it is. This will go down over time. Accept it and design around it and you get long life in a working system. Otherwise learn to be happy buying new batteries.
  • RossmanRossman Solar Expert Posts: 178 ✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    Anyone else pick one of these up?? I'll be trying to set mine up in the next few days or so and was hoping someone else had some experience with this unit they might be able to share...

    Happy holidays,
    mark
  • HandyBobHandyBob Banned Posts: 31
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    vtmaps wrote: »

    About the rPC .... doesn't that depend on charge rate? I was under the impression that rPC is a measure of charging efficiency. Lower charge rates (within limits) are more efficient.

    Also, what about temperature? Temperature affects battery internal resistance which affects charge efficiency, capacity, and Peukert factor. Does the 2030 take temperature into consideration? Does the 2030 use Peukert factor (of loads) to calculate SOC?
    --vtMaps

    Every time i get on a forum I end up regretting it.... Very soon I will not come back to this one. Ya'll have fun.

    rPC is a simple counter, not taking any inefficiency into account. Every battery manufacturer gave Ralph some guideline about increased amp hours needed at a MINIMUM to actually get their batteries recharged and healthy. I find it very telling that the chemistry is all the same, but there are so many differing opinions. When I talked with Crown about how my batteries act, with SG up to 1.295, they loved it. Lead is not corroded by acid. It is inert. If it causes problems, the batteries are not built well. Many of them obviously are not. I'm not going to start naming them, but why do you suppose NAWS is now selling Crown? I doubt it is because of a better profit margin. The only problem with overcharging is use of water and truthfully, a healthy battery will reject amps, simply not accepting enough to cause loss of electrolyte. That is an old general consensus tale. If a battery is losing electrolyte at a high rate, something is wrong with it. I see my system at over 30V with only a few amps when getting ready to float. That is the right thing. When I am in float, I see 1.8A at 26.8V give or take due to temperature, with 800ah of storage. That does not cause water use. Higher summer temps have caused my water use to double but I would expect that. Anybody with a lick of common sense would.

    Ralph does not believe in Peukert's and I think he is right. Everybody is entitled to their opinion. I owned a Link for years and I think it was an over complicated blank blank blank. I ended up giving it away. When I found Trimetric it was like a breath of fresh air. Maybe you should just give Ralph a call. He can explain where he is coming from and if anybody thinks that I have a lot of experience, compared to Ralph, I am a novice.

    One of the things I love about him is his take on MPPT. You'll never find anybody selling solar equipment to actually come right out and give you the truth about that. Like me, Ralph doesn't sell solar equipment. We just live with it. I have repaired MANY systems that didn't work, though. He won't print his opinion, but he'll tell you over the phone. After owning a MidNite Classic, I can say that it works. I have also installed many Tristar MPPT units and they are about the same. However, MPPT does NOT do anything like they want to claim. Plus, the same guys now at MidNite designed the Outback and they were less than honest about it. How is that for a nice way of putting it? (One of those guys admitted that to me over the phone, so don't start in on me.) I typically see 1600 - 1700W from my 2000W on the roof. Yes, I have seen 2400W in perfect, very cold conditions. That lasted for minutes, not hours. This life is about amp HOURS, not minutes. Most of the time it is my batteries limiting the amps they will accept that dictates the amp hours stored, not what MPPT is doing. MPPT only really works early in the charge cycle. Having experimented both ways, I have a different take on it. To me, it is a way to limit voltage drop on the incoming wires and to get a bit more when you really need it, but I worry about overcomplicated controls in our scary world where a computer failure could shut us down. I will never get into computer logging.... who cares? I am 63 and I just want to live decently.

    I doubt the loss of storage due to temp can be made automatic. I simply program a bit pessimistically. These meters are never perfect. Close enough is good enough sometimes. Being overly anal about it just fouls up your Karma, dude The goal is to not abuse the batteries, isn't it? Knowing exactly is not required for that and being a bit cautious is good. The 2020 will disappear. I have run the 2020 & 2025 in parallel to see the difference. The 2025 is more accurate. Every version he makes is an improvement over past versions.
  • westbranchwestbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    HandyBob wrote: »
    Every time i get on a forum I end up regretting it.... Very soon I will not come back to this one. Ya'll have fun.

    MPPT only really works early in the charge cycle. ......
    To me, it is a way to limit voltage drop on the incoming wires and to get a bit more when you really need it.....

    HB , I agree about the MPPT working best in Bulk, can you expand on 'limit Voltage drop" a bit more.

    I'm with VT and enjoy a different perspective to get some cobwebs out of the closet...

    tks
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    westbranch wrote: »
    HB , I agree about the MPPT working best in Bulk, can you expand on 'limit Voltage drop" a bit more.

    I think he is writing about the MPPT advantage where higher string voltage gives an advantage with respect to voltage drop on the combiner to controller cable.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • HandyBobHandyBob Banned Posts: 31
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    Right. Using MPPT lets you save money on cable. However, once you have installed it, you cannot go back to PWM and see the actual difference MPPT makes unless you want to pay for duplicate sets of cables. An actual study both ways with identical loads is virtually impossible except in a lab. Those of us living with the stuff cannot do that. I made my mind up by watching my RV system and my building system side by side, watching what each did in identical solar conditions. 10 - 12% improvement in average conditions during spring & fall, almost nothing in summer. Winter is when it helps. Down south it doesn't do a lot. Plus, some of the cheap MPPT controllers do not actually track, being factory set. They lie... imagine that!

    Boy are we off topic now! Oh well, next I would love to talk about what you get from battery experts when they are talking, not in their brochures and emails. Crown sells AGM's but their factory guy agrees with me that the only advantage they offer is no maintenance and they are easier to ruin by undercharging than flooded. Good flooded batteries last just as long as AGM's and are much more tolerant of abuse. It is very difficult to monitor AGM's and know if you are doing things right. If you screw up, they are toast. The thing that AGM really has going for it is that the dealers make more money selling them. (Just like MPPT controllers) People using AGM's need to stay current with what Life Line is saying. They now say to equalize (over charge). Cheap AGM's are not worth buying. Their track record is horrible.

    And Interstate....... Somebody should ask those "outrageously reliable" folks what battery they put in their NASCAR racer. I have had a lot of negative experience with them that I cannot repeat, but it is real. And if you ask them for charging guidelines even today, they will supply a chart that is wrong. Ask yourself why. One of my friends has a bus with 1000W on the roof and he runs L-16's. Years ago he ignored my advice when replacing the Trojans that he had ruined by undercharging because his system had been done with the help of one of those Quartzsite dealers. We rewired the system and fixed it, but it was too late. Less than 5 years later, two of the six Interstate replacements had bad cells. This was AFTER he had to make them replace his first set that never took a full charge. That fiasco cost him a lot of time & money for travel and give some thought to what he had to do so his food didn't spoil each time he took the batteries out and drove them to the dealer. I remember him shaking his head as we did the hydrometer tests and saying "I seem to remember somebody warning me about this."

    My opinion on overcharging being good is based on feedback from customers and friends who have gotten many more years of life from batteries than most believe possible. This summer it was a friend I helped over 8 years ago. His Trojans were failing, after being charged by a Tristar PWM set at 14.8V plus temp compensation and monitored by a Trimetric 2020 in a rolling home that almost never gets plugged in. He bought that thing used and we moved the solar from his old rig to it, but did it right that time. He wanted my advice on what batteries to buy this time. When I asked how old the Trojans were, he said ELEVEN years. Nuff said. Cheap batteries are only good for rich people who don't mind having failed batteries when it is most inconvenient and buying them twice as often.
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    HandyBob wrote: »
    Crown sells AGM's but their factory guy agrees with me that the only advantage they offer is no maintenance and they are easier to ruin by undercharging than flooded.

    One other consideration.... peukert factor and voltage sag.

    When my flooded batteries are at or below 75% SOC, I can't do a laundry without pulling the voltage down to my low voltage disconnect (24.0 volts), even though the batteries have more than enough capacity to provide the 300 watthours that I need. An AGM battery of identical capacity would have no problem providing the 500-600 watts that the washing machine draws.

    But I do agree that flooded are more suitable for most off-grid situations. I do my laundry when its sunny or when the generator is running.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • HandyBobHandyBob Banned Posts: 31
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    vtmaps wrote: »
    One other consideration.... peukert factor and voltage sag.

    When my flooded batteries are at or below 75% SOC, I can't do a laundry without pulling the voltage down to my low voltage disconnect (24.0 volts), even though the batteries have more than enough capacity to provide the 300 watthours that I need. An AGM battery of identical capacity would have no problem providing the 500-600 watts that the washing machine draws.

    But I do agree that flooded are more suitable for most off-grid situations.--vtMaps

    Is the above based on personal experience or something somebody in the battery business told you? I have heard from people using them that Lithium batteries hold their voltage better, but I see no reason why AGM would be much better there, except that their self discharge rate is a bit better. They are basically the same except for the material used to hold the lead in place. The reason they hold fewer amp hours per pound is that they must be charged at a lower rate to prevent venting. Now Life Line has figured out that they suffer some of the same problems from undercharging and they recommend light equalizing.

    My biggest problem with the world in general today at 63 years of age is that I now know how much companies lie in their marketing. You really can't believe everything you see in glossy brochures. I didn't get into the solar world yesterday; it was 1999. I have seen the evolution and figured out on my own the truth about many things. I have now owned 7 different charge controllers and tested a few more, so when I talk about things like MPPT or batteries I'm not basing it on the glossy brochures. When I saw a solar dealer telling a customer that he could buy MPPT instead of a new panel and get the same result was when my BS meter went right off the scale (sort of the beginning of my finding the truth). This was one of those guys who had no solar wire bigger than #10 in stock back then. Today the same guy uses a maximum of #6, still in business & still hoodwinking people daily. I heard from one of his former employees that the guy laughs about the law suites he has been hit with.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    HandyBob wrote: »
    My biggest problem with the world in general today at 63 years of age is that I now know how much companies lie in their marketing. You really can't believe everything you see in glossy brochures. I didn't get into the solar world yesterday; it was 1999. I have seen the evolution and figured out on my own the truth about many things. I have now owned 7 different charge controllers and tested a few more, so when I talk about things like MPPT or batteries I'm not basing it on the glossy brochures. When I saw a solar dealer telling a customer that he could buy MPPT instead of a new panel and get the same result was when my BS meter went right off the scale (sort of the beginning of my finding the truth). This was one of those guys who had no solar wire bigger than #10 in stock back then. Today the same guy uses a maximum of #6, still in business & still hoodwinking people daily. I heard from one of his former employees that the guy laughs about the law suites he has been hit with.

    Amen.

    I don't know how many times I've mentioned having decades of experience and it just doesn't seem to matter to some people (anymore than the degrees do).

    The biggest advantage to MPPT is the flexibility it gives in array design/panel choice. Under typical conditions the power increase over PWM is only about 10%, and that sure isn't enough to justify spending hundreds more. Take the place of an entire panel? Never.

    vtmaps remark about the AGM's being able to handle greater current in/out than FLA's is correct; the Voltage sag differential is not huge, but can be enough to make things work. LiFePo's have almost steady Voltage across their SOC range but have other complications/disadvantages.

    As always, no one has to listen to me. But the people who do all have working systems.
  • BB.BB. Super Moderators, Administrators Posts: 30,642 admin
    Re: Conext Battery Monitor : A serious threat to the Trimetric?

    I agree that MPPT solar charge controllers are not "worth the money" if anyone just swaps out a PWM (in a properly designed system) for MPPT controller for the "extra" 10-20% output (per the advertising). Those power numbers are really only valid in very cold weather (sub freezing/clear/sunny days). For summer weather and proper Vmp~17.5 volt panels, there is very little difference in output between PWM and MPPT in properly designed systems. And adding an extra panel or two to an existing PWM controller (and adding a larger/extra PWM controller if needed) can be the most cost effective.

    For new systems and/or systems with longer cable runs from the array to the charge controller. The savings in copper cable costs and the (usually cheaper) "GT" solar panels can make a MPPT controller cost competitive. It is at least worth the effort to do a couple paper designs and see what works out best (expensive "12 volt panels" + cheaper PWM controller; or "cheaper GT panels" with Vmp~30 volts and an expensive MPPT controller).

    In general, for 400 watt or less systems, PWM controllers are usually fine (although, MPPT can be cost competitive). For 800 Watt and larger systems, MPPT+GT Panels is usually the more cost effective solution.

    And I agree, I like charge controllers and inverters that use passive cooling (large external heat sinks). Adding fans adds another point of failure (fans need replacing, draw dust, moisture, and bugs into the electronics, noise, etc.). But the size and cost of large heat sinks can be a pain too.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    BB. wrote: »

    And I agree, I like charge controllers and inverters that use passive cooling (large external heat sinks). Adding fans adds another point of failure (fans need replacing, draw dust, moisture, and bugs into the electronics, noise, etc.). But the size of cost of large heat sinks can be a pain too.

    -Bill

    Well the boys did good on the MX60: still running, fan (which hardly ever comes on) and all.

    Much has to do with where the unit is installed, and how close to maximum capacity it is required to run for how long.

    In 'bad' conditions that undesirable fan can keep the working components cooler than a mere massive heat sink will. This is why engineers make choices; which is the most effective solution for the most likely conditions? Since no two installations are ever alike it's hard to get it right.

    I know one use of MidNite controllers where the owner complained about the fan being on "all the time" where the units were mounted wrong, in a low-ventilation area, and asked to carry full current from wind turbines 24/7. Gosh, they got hot. Who would have guessed? Well anyone with an ounce of common sense and a smattering of engineering experience.

    Too often people form opinions of products based on one or two uses where they may not even be the right choice or they attempt to do comparisons from anecdotal evidence alone having no idea how much is involved to design an unbiased test. This isn't fair to the manufacturers anymore than their 'best case' claims are to the end users.
  • vtmapsvtmaps Solar Expert Posts: 3,738 ✭✭✭✭
    Re: Conext Battery Monitor : A serious threat to the Trimetric?
    HandyBob wrote: »
    Is the above based on personal experience or something somebody in the battery business told you? I have heard from people using them that Lithium batteries hold their voltage better, but I see no reason why AGM would be much better there

    It's based on personal experience. It's especially true in the winter when the batteries are at 55° F. The voltage sag under load is because flooded batteries have higher internal resistance (and peukert factor) than AGM batteries.

    Usually when choosing a battery, the watthour capacity is the major concern. In some systems, if the current draw tends to be greater than C/20, it may make sense to use AGM, rather than using flooded and having to oversize the watthour capacity.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
Sign In or Register to comment.