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Forum Index : Solar : Tracer MPPT controller/PowerMaster PM-300
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
I am running a Tracer MPPT 20A solar controller and a PowerMaster PM-3000L inverter Tracer MPPT 20A Pure Sinewave inverter in a 24Volt battery system. Some days the Tracer thinks it has over-charged the batteries, although they are only at about 30Volts (equalising). Then the PowerMaster inverter shuts down even though it is suppose to be able to work up to 32Volts. I find it odd the the charger can "over-charge" the battery system in the first place. To prevent this from happening, as I have a situation where I do NOT want to lose mains power, I have built a diversion load that comes on at 29V. I will start to monitor the system with a oscilloscope and try to induce this condition in order to find out what is wrong. Does anyone have a similar setup or seen a problem like this? My current theory is that the Tracer puts out "rubbish" when the batteries go above 30Volts and "tricks" the PowerMaster inverter into thinking there is an over-load situation. Cheers, Dave |
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yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
I have had a similar problem with a system and it bugged me for a couple of years before I found the problem. The inverter voltage sensor was always reading high. the fault was high resistance between two battery cells in one bank of a parallel setup. I don't know if it was a floating earth voltage or some kind of pulsing feedback happening. In the end it got so bad the thing would not power up. I fixed the fault but it still reads high, not as bad as what it was, so now the setup is due for new batteries, I will be interested to see if that makes a difference as these ones as totally shot. I'm confused, no wait... maybe I'm not... |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
yahoo2, As one of battery lead terminals was a bit warm under heavy load I ended up replacing all the inter-connecting crimped leads with properly soldered ones. I have measured the drop on all cables to ensure integrity. The negative lead on the solar controller goes back to the battery negative point, however I have the positive lead of the Tracer solar controller near the inverter end of the BIG positive lead (20cm of welding cable) from the battery. I will be able to get my hands on a high-power adjustable bench power supply next week so I am going to check that the power inverter really does cut-out at 32Volts (as per the specs). Reading through all the solar postings on Otherpower I came across a recommendation to equalise the batteries at 32-33Volts, which is definitely above the cut-out voltage on the PowerMaster! As there is no external connections I assume the "inverter voltage sensor" is just monitoring the actual input voltage to the inverter. I do not have any display on the inverter. I measure with a DVM right at the inverter terminals. If the inverter is sensitive to any "pulsing feedback" I will be even more concerned, as I also want to charge the batteries with one of these chargers. I imagine there will be some "pulsing" going on with this added to the system. I hope to be able to run this charger off ~230VAC 3 phase from the microhydro, then rectified. I have read that most of these types of chargers rectifies mains in the front-end of the unit, so I just need to dive in there and find the right point to connect my source. Seems the Tracer MPPT units are not very common in Australia/NZ. |
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yahoo2 Guru Joined: 05/04/2011 Location: AustraliaPosts: 1166 |
When I was talking about feedback (or perhaps capacitance) I meant internally in the inverter, the batteries themselves tend to dampen any pulsing. I guess you could try a test with a single string of batteries to see if that makes a difference or a pair of fresh car batteries. Maybe the voltage sensor is a bit out, or dry jointed? strange things can happen with DC power, the first system I ever worked on had 7 battery banks, the earth voltage at each negative junction terminal was different, power flowed between the banks with everything switched off. taught me some valuable lessons about working methodically. I have pushed a bank of trojan batteries to 32 volt (and another but I don't recall the brand)for equalisation, 30.6 V is about my max limit for everything else, I worry about heat buildup. I just use a 30 volt power supply that has a 100% duty cycle and +-10% calibration adjustment it looks rough but provided the output is about right for the batteries it seems to do the job for an annual manual EQ. I'm confused, no wait... maybe I'm not... |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
On the topic of battery impedance: This paper here suggests that lead-acid batteries on float look like a pretty low impedance (resistive part) well up to 1MHz. I think that is the meaning of the log(frequency((Hz)) scale. But, for the reactive part they appear to be quite inductive above about 10kHz, I'd have to look up how to convert +60degrees phase shift at 10kHz to inductance. I now have a 33Volt 30Amp bench supply to test the system with. I will see if disconnecting one bank makes any difference ... good idea. Dave |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
I have identified a design issue with the Tracer 2210N MPPT charger. This issue perhaps only affects my PowerMaster pure sine wave inverter. Next step is to talk to Tracer support. |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
Just to close this issue: - email from PowerMaster state that the high-voltage cut-out point is 30.4Volts, for the PM-3000L. This does not agree with their sales literature (32V). As the Tracer will try to charge batteries above 30.4Volts, this seems to point to an "incompatibility" issue! |
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anteror Senior Member Joined: 06/10/2009 Location: FinlandPosts: 189 |
I have tested several MPPT and other solar controllers... NOT good and do not work reliably. The less vulnerable and complex electronics, THE BETTER You DO NOT any of these. You just connect the solar panels directly to load your batteries. Nowadays the panels between 235-260-280W are all suitable to be connected directly to load batteries, in to the 24V system. Loaded optimal voltages are beteween 28-31V. So, they do need any controller to load with full power. I have 11 units of 250W solar panels and have connected all in parallel, in a 3 unit groups(one group is 2 units..) and these groups have 20Amp fuse.(factory recommendation). I have tried and tested these with several MPPT and I get exactly the same power without any controller I use this DC voltage control relay, to guide the overproduction, where I want and protect against overvoltage, overcharging; http://www.takowa.fi/fi/kauppa/1-vaihe-ac-dc/hrn-64 You connect this unit to guide/control overvoltage/overcharge via your inverter, AC 240V or in some countries 110V Ac, to any chosen consumption. You can connect panels and wind power, so much you want and guide all the power, with these cheap and reliable relay / relays to any chosen consumption. Etc Antero My windgenerator. Has been working without any faults for over 6 years now; |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
Antero, I would agree the simpler the more reliable. With a direct connection I would still need a diversion system so that the input voltage limit of the inverter was not exceeded. This would only happen on long sunny days when I wasn't using much power, ie when away from the house. I have seen up to 15Amps off two panels that test at 5.5Amps short circuit. So, there is some benefit from the MPPT controller, with my panels (40Volt open circuit). As the price of PV panels have dropped a lot over the last few years I do wonder if it would have been better to buy an extra panel and just use a PWM controller. If the panels had a lower open circuit voltage I could see that there would be little benefit from using a controller, other than getting consistent control of charge rates and equalisation regimes. How do you manage your charge rates and equalisation? Cheers, Dave |
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anteror Senior Member Joined: 06/10/2009 Location: FinlandPosts: 189 |
Dave; I use Dc monitoring relay, as I wrote in my message.. I do not know how to begin..equalisation, that is JUST bull sh*t !! But I begin with this. In New York all the cars worked with batteries, first. First ever massproduced car was meant to be electric car. Henry Ford and Edison had developed this together. Then somebody found oil.. Edison battery was developed for this.. for everlasting and easy to maintain and charge electric car battery, to last.. etc etc Batteries, that worked and those would work.. to the present day http://www.nickel-iron-battery.com/ Edison Battery company developed this battery, but the worlds biggest battery company at that time, bought the Edison battery and STOPPED manufacturing and devoplement of this battery. It was too good battery. It was the same as light bulb BIG fraud, which has now been revealed, at our time. Too good battery.. -Made of of common and cheap metals and non-poisonous fluid, which can be used as fertilizer.. -You can charge these with any power, very high or low, not sensitive for anything. -You can take power to the knees, no harm done to make any particels to the bottom of batteries, to make short circuit.. which kills lead acid batteries. Unlimited cycles. -After using decade(s), you just rinse and wash the batteries with water and poor the battery water for soil improvement.. -New non-poisonous battery chemical in and batteries have full capasity ! NO wonder, it was too good. I have NICAD batteries, which are old used ice breaker ship batteries. They have almost the same features, but not even near so good as NIFE Edison batteries. They have worked for over 30 years since manufacturing. I have used them for 15 years now. I have them 80 units 1,2V 500Ah, I have connected them in 4 X 20 unit croups to make 24V 2000Ah. They need to be run really empty once in the year. That is all the maintenance they need. You can charge them with any power and take.. BUT they will lose capacity year after year..and i can not rinse them with water and the fluid is very poisones etc SO.. good batteries is just, what we need, to be INDEPENDENT. Solar and wind power is easy to have, to your own house in our time. I will buy Edison NIFE batteries to my house after NICAD batteries. That is what I want to leave after me to heritage to my children and to their children for decades to come. Something truly sustainable.. Antero Here you can see half of my batteries. They say NIFE but they are NICAD batteries. NIFE is the brand of manufacturer, which is nowadays SAFT batteries. Made in Sweden. |
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evpower Newbie Joined: 01/10/2013 Location: CzechoslovakiaPosts: 1 |
The Tracer series have a over current protection, they will make a "fault" status when the current is too high. However if the current is TOO HIGH, the unit may burn inside. The Trace controller is not a fuse. Always install an external fuse to protect against high currents. For Tracer products, check here http://www.ev-power.eu/Solar-GridFree/?src=EVSEJ1310 The tracer models have the RJ45 port to allow data logging. The Solar Controller Monitor makes the connection to PC. http://www.ev-power.eu/_d3548.html?src=EVSEJ1310 Hope this helps. |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
As recommended in their manual I have a fuse on its output. The highest current I have seen is 15-16Amps which is well inside its 20Amp capability. The Tracer may have been indicating that it had "over-charged" the batteries due to the behaviour of the power inverter connected across the batteries, when the battery voltage went over 30Volts. I now have two diversion circuits that ensure that the battery voltage never goes above 29.5Volts. One lesson to learn from this is that perhaps not all solar chargers are compatible with all the different brands and models of power inverters ... attached to every make of battery and in various states of health. In other words, you may have "system" issues to deal with :) |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
After further discussions with the supplier and an installer ... Seems there can be system issues especially with solar controllers that have an equalising function. I have been told that Trace and Outback can disable the equalise function. For my unit (2210RN-2215RN-TRACER) the recommendation is to select the "gel" setting when using flooded cells, which also disables equalisation and lowers the boost voltage slightly. Now, I get to choose when I do equalisation. The top-end product from Tracer evidently allows much more customisation. |
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Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
I have a Outback MX60, you can disable equalize, have it work automatically or do it manually. Also you can set the time and voltage to equalise. There are only 10 types of people in the world: those who understand binary, and those who don't. |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
Madness, I have been told subsequently that this unit can disable the equalisation by selecting the SLA option. The "boost" voltage is a couple 100 millivolts different, than for lead-acid. Currently, I am running the system without the solar controller and managing equalisation manually. Because my PV panels are rated at 36V for Pmax I am only getting about another 10% or so in max power with the MPPT controller. When the system is unattended I will probably put it back in to take better care of my batteries. Cheers, davef |
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Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
Equalization is there to get rid of sulphation, what would be the point in disabling it for flooded lead acid batteries? There are only 10 types of people in the world: those who understand binary, and those who don't. |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
Because automatic equalisation was taking the battery voltage above 30.4Volts, which was the shutdown voltage on the inverter. |
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Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
Yes that would be a problem, have you consider adding a Desulphator ? These draw minimal current and are supposed to be a more efficient way to keep your batteries in good condition. There are only 10 types of people in the world: those who understand binary, and those who don't. |
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davef Guru Joined: 14/05/2006 Location: New ZealandPosts: 499 |
Thanks for the link. I actually built one of these about 2 years ago, but never got it to work. I even put a peak detector circuit on it to see if there was anything more than the raw DC level. I'll have another crack at it. Cheers, Dave |
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Madness Guru Joined: 08/10/2011 Location: AustraliaPosts: 2498 |
I am about to build a few of them also, have gotten good source of used batteries to revive. Here is another one, I think I will try. High power desulphator. There are only 10 types of people in the world: those who understand binary, and those who don't. |
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