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so, finally i decided for this machine, as that seems to be better price/value ratio. however, i expect you may not agree 
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Well I like it. A step up from from the PL6. Just one question. What power supply are you going to use on it?so, finally i decided for this machine, as that seems to be better price/value ratio. however, i expect you may not agree
http://www.store.revolectrix.com/Pro...200/GT1200_152
You will need one to take full advantage of it. However with the right Power Supply you can charge any battery type up to 24 volts @ 360 AH. With a 12 volt 50 amps gives you 600 watt charging, and with a 24 volt @50 amp / 36 volt 35 amp supply charge at 1200 watts.
Discharge is a bit limited @ 10 amps, but can be done at 3.2 or 12 volts. What that means is you can wire the batteries in series to do the Bulk Discharge at 10 amps. Even if at full charge is 100 AH so you would be looking at 10 hours max while you sleep. Then once that is done, then wire them in parallel and discharge down to 2.4 volts while you sleep.
To discharge real fast, just hook up an Inverter and run a big load until it shuts off, then parallel the cells to take them down. Also if you have say a 12 volt car battery, discharge it, and use Regenerative Discharge at 12 volts. You can do regen discharge at 40 amps and it will charge the car battery with your LFP batteries.
Additionally it would be a good idea and a piece of mind to make you a Balance Cable so if you want to use discharge the cells in series through the charger, it will monitor cell voltages and shut down if any cell falls below 2.5 volts. Just be sure to wire them all in parallel for th efinal discharge down to 2.5 volts. Once you get it and start reading this will all make since too you.
I normally would not recommend Chi-Com Junk but you can buy a decent Turnigy 1200 watt Power Supply (24 volt 50 amp) to take full advantage of your charger. . An alternative is a Turnigy 500 Watt Power Supply (25 volt @ 35 amp) with limited charge which is still a beast. Shop around you might find a better price at some of the On-Line RC Hobby Shops. With your charger and a good power supply you can charge anything anyway you want.
Last edited by Sunking; 01-09-2018, 06:44 PM.MSEE, PEComment
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Racmaster - you know that you've now badly violated the KISS principle right?
All the above is very good info. However, if you were going to stick to a kiss concept, and charge with a standard charger (no lead-acid desulfation pulses, behind-your-back 15.6v lead-acid eq's!), and provided that the cells had been individually charge first, this charger has proved its mettle with my LFP on a pack-level basis. ( I actually use the smaller 15a vesion with my 40ah batt):
Samlex SEC-1230UL. Set dip switches for GEL, which is a cv of 14.1v. You get to watch the steam gauge during charge and taper:
http://www.samlexamerica.com/product...l.aspx?pid=171
Note that the KISS principle does NOT imply cheap! - as you've seen when you put a very nice programmable hobby charger along with the required power supply. You don't want to use too little current, so anything below about 0.1c is not recommended due to inefficiency while charging - which means spending waaay too much time at high voltages. Those who would put a wall-wart on a 90ah battery may just find the charge circuitry timing out if they are lucky, never being able to charge.
Just remember - you bought into the high upfront-price of LFP, so don't cheap-out trying to McGiver junk together and save a nickel. That's how you kill batteries, regardless of chemistry.
Thing is, all the info above is good stuff, but eventually YOU will have to let us know how it works out. KISS means a lot of babysitting at first to make sure things are going right, and if not, pulling the plug. If you want total hands-off automation, that's one thing, like if you were going to let your neighbor use your bank.
Where did you get those 90ah Winstons? I hope they were new and NOT used!
Last edited by PNjunction; 01-09-2018, 08:41 PM.Comment
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sunking - my first plan is to wait for the new charger, then connect it to all cells to let it monitor the vpc. discharge the battery safely to about 3.3vpc by standard usage(on solar ctrl), then disconnect from solar circuit and replace with my agm bat. solar circuit will continue to work, just the battery will be replaced. afterwards i plan to use the regenerative discharge feature of the gt1200 charger, which should transfer the energy to the agm as much as agm will be able to absorb... therefore it will be much faster then standard heating discharge...
as soon as this will be done, solar ctrl will no longer charge the agm, or just with some few amps, most probablty switched to float charging state. HERE i connect the new gt1200 to the load output of the solarctrl and the new machine will take care for most perfect charging possible for my LFP. in fact it will charge with as much as sun will provide, so up to 30a, which should be much enough. maybe it will take 2 days of sun, as currently it shines 3hrs/day if lucky... would that be problem, if the battery will be charged in 2 steps, but will not be discharged between them, just waiting for the charging process to continue next day...? should not be as long as the logging will be on and i will se all the parameters connected with real capacity counter... pls confirm
if that could be fine, i will not need any other investment into power source. lfp will be charged from solar and gt1200 will be sucking from load output of solar ctrl to charge the old leadacids and anything out there... however, i plan to use some of my old ACtoDC power sources for the future, especialy thinking about notebook charger and old pc power source. unfortunately they will not provide 600 wats, but thinking about joining 2 different sources into it - wasnt checking this idea too much, so its probably BS, maybe not. what do you mean? also i have old smart leadacid charger30a, maybe using that as a power source after some tuning inside the charger could also work...??
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PNjunction - welcome back. few days ago i was thinking about contacting you regarding the phase, where this thread developed from first question of OVD vs CLV... of course, most of my ideas were based on what i red from you, regarding running lfp without balancers and also the kiss concept. and now i found you came back
but, to be honest, now im not exactly sure to what specific part of this thread your answer was related to...
to your question, ive got the lfp from this site, seems to be a vendor for lot of european eshops, so also the prices are a bit better
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Just one very minor problem here, no big deal. It will not work.
Solar Controllers must have a battery connected to the output as that is where they get there power from and know what voltage the battery is. With panels connected and no battery connected at worse can damage the controller, and at least will not even turn on. As PN tried to tell you switching to lithium does not imply inexpensive and what I have been trying to tell you. You do not need a BMS or a monitor for normal operation as PN and I have been telling you, but there is a requirement of some special equipment for the Initial Balance.
I am not certain because I have not tried, but I think you can use a standard battery charger made for lead acid batteries as a DC power supply because that is basically what battery charger is to start with. It does not need to be a 12 volt 50 amp (600 watt) supply. But here is the thing. You bought a GT-1200 a great hobby charger that will charge anything, but you do not have a power supply to use it. What is wrong with that picture? Basically you bought a car without an engine.
MSEE, PEComment
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agm is what you missedComment
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OK was in a bit of a rush with last post and only had time to tell you what would not work. Now lets discuss what you can do with what you have. OK relax I think you can work around not having a power supply. You say you have a AC powered Battery Charger and AGM battery. That is all you need.
Charge up the AGM battery first with your battery charger. Once the AGM is charged up leave the Charger and AGM connected, then connect your new GTX1200 to th eAGM battery and now you have a power supply to work with to charge up cells. Only caveat I can add i slimit charger current to whatever current the charger can supply. If you go over that the AGM will have to make up for the shortage which is OK for a short time.
For discharge still requires a DC power supply to power the GTX1200, but the power demand is very low and just about any 12 volt source will work so just use the AGM battery, the AC Charger or both like above. In Discharge MOD the power is dissipated by the GTX1200. At 10 amps @ 12 volt is 120 watts, so the GTX will get warm and the fans will run.MSEE, PEComment
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No I did not miss AGM, I ran out of time.MSEE, PEComment
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so in fact i will use the FLOAT mechanism of the charger as power source, right? easiest way, good idea.
however, just teoreticaly, what would happen if i connect 2 different dc power sources as an input? in either serial way increading voltage or paralel to increase amperes? as the source of input power for gt1200...? of course under 32v input limit...?Comment
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Close but no cigar. No you do not want to use FLOAT because of the lower voltage. Your GT-1200 is a POWER CONVERTER not a DC CONVERTER.
Power = Voltage x Watts.
Lets say you have a 20 amp battery charger. So answer these two math problems and tell me which has more power.
13.8 volts x 20 amps = How Many Watts?
15 volts x 20 amps = How Many Watts?
Did the light turn on illuminating the meat between your ears?
Read the specs on your converter. With 12 volt supply is limited to 600 watts. At 24 to 36 volts is 1200 watts. Crank the voltage up as high as you can get it for the AGM battery Bulk/Absorb.
Not theoretical, it can be done, not in series but in parallel. Example you can use your solar charger, AC Charger, and AGM battery as the power source. Well the battery is not really a power source, it just stores energy and regulates the voltage.
It may not work like you expect because solar is not a STIFF SOURCE nor is it the Highest Energy Source. The highest energy source is the charger. Solar would not be used unless the power demand exceeds what the Charger and AGM supplies.
Everything gets connected at the AGM Battery Term Post I mean everything Solar, AC Charger, and GT1200 all connected directly to th eAGM battery Term Post. All in parallel. You cannot connect the solar charger in series with the AC Charger to get 24 volts. Will not work. So DO NOT TRY IT or you will be sorry when you see the magic smoke leaving your solar charge controller and AC charger.Last edited by Sunking; 01-11-2018, 05:17 PM.MSEE, PEComment
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thanx, good news. what i was in fact thinking was using two redundant power sources from old ibm server i have. it has several 12v outputs from 6a to 14a, together limited to 360w, which should be about 30a. as redundant, there are two identical pieces of them, getting up to 60a of power. as it is a server power source, i expect it to be highest quality. so maybe we are there? no need to search around, just connect all 12v outputs of both power sources in paralel, connecting to gt1200 and enjoyng its full power?Comment
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I too ended up with a GT1200 like racmaster and was hunting for an affordable salvaged server PSU to run it as SunKing suggests. I ended up using this site. The fella doesn't run it like an instant-delivery Amazon shop...but the prices are great for what you get if you can stand to wait a couple days for shipping (he basically mods them on-demand). If you email or chat at him via the site he is willing to put custom connections onto the PSU for a few more $, within reason. Don't forget to grab an adapter to go from whatever is on the PSU (likely 4mm banana jacks) to what your charger takes (EC5 on the Revolectrix stuff). I had to get mine off eBay. Obviously not a hard thing to make yourself, but if you don't have the connectors lying around already it's cheaper to buy pre-made.
- Jerud
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1220W array (4x 305W Astronergy panels @ 48V)
1000Ah LFP house bank (5P4S HiPower 200Ah cells)
MPPT solar charge controller (MidniteSolar Classic 150)
2800W PSW Inverter (Magnum MS2812)
ME-RC, Trimetric, and JLD404
2001 Fleetwood Prowler 5th wheel 25 foot, self-rebuilt
www.livesmallridefree.comComment
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Racmaster, i just learned (last night at 3am) that our charger (GT1200) won't discharge 1S below 3.0V in non-regen mode. I learned this because after 14 hours on discharge, the process cancelled itself with an error box, inconveniently obscuring the Ah reading
. The menus will let you specify a lower voltage, but it will throw this error on you and you may lose some data you were hoping for. Tech support says this is not something that can be circumvented. The manual does document the error code (SC041), but does not elucidate that 3.0V is the magic number. Just something to keep in mind.
The solution is either to regen discharge into a 12V battery or to discharge your cells in series...but of course then you can't measure Ah-per-cell. I had wanted to avoid regen charging because it ties up my truck (the only 12V batteries i own)...but i guess that's just what it takes
PL6 and PL8 owners: Does this restriction exist on those chargers?
- Jerud
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1220W array (4x 305W Astronergy panels @ 48V)
1000Ah LFP house bank (5P4S HiPower 200Ah cells)
MPPT solar charge controller (MidniteSolar Classic 150)
2800W PSW Inverter (Magnum MS2812)
ME-RC, Trimetric, and JLD404
2001 Fleetwood Prowler 5th wheel 25 foot, self-rebuilt
www.livesmallridefree.comComment
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good to know, zamboni...
i will test this later and let you know. maybe, with so many lfp batteries you could do regenerative discharge between them, just split them... but this will make them unbalanced, of course... hard to say, i saw some experiments with connecting some resistors or another kind of "power absorber" on the second side of regenerative discharge. maybe the local experts will offer more ideas.
regarding the PSU, that site looks fine and this seems to be the best choice of value/price power source. i spent a while studying peoples experience with standard PC power supplies and they mostly do not seems to meet the specified power, so you would need to go for top PC PSUs to get some serious amperes and those are too expensive again. another plus, server psus are designed for nonstop production, which makes them much more heavy duty, then desktops. i currently search for some info about transformation of 2 redundant ibm dps-350mb having together 50a. currently im hanged on where to connect AC input.
based on this pinout scheme, it should be A2 and A4. do you have an experience with this stuff?
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