How many amps? 8 fully charged 225 amh 6v batteries in series? Trying to derive amps, not amp hours. Thanks
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RCinFLA
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From voltage and AH rating I assume these are golf cart lead acid batteries.
Should not continuously draw more than 100 amps from them. At full starting charge level, within about 15 minutes they will drop down and level off at slightly less than 48vdc for eight of them in series at 100 amp draw. If 100 amp load maintained, over next hour they will drop to about 45-46vdc and you should not continue drawing this current much beyond that time.
Should not continuously draw more than 100 amps from them. At full starting charge level, within about 15 minutes they will drop down and level off at slightly less than 48vdc for eight of them in series at 100 amp draw. If 100 amp load maintained, over next hour they will drop to about 45-46vdc and you should not continue drawing this current much beyond that time.
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Goboatingnow
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110AH at 48v nominal , assuming 50 % discharge , typical of lead acid
400bird
Solar Wizard
amh isn't a unit.
mAh is milli amp hours.
If you're batteries are rated at 225 mAh, that's not much storage. But, if you're looking for the max amp discharge, that's just straight listed on the spec sheet. It doesn't matter how many are in series, the spec is the same as the current is the same everywhere in the circuit (the same through each battery)
Yes, they are lead acid golf cart batteries.
I've got them wired in series for 24v. I'm trying a 2.1 cubic foot mini freezer that requires 115v - 15 amps as stated on sticker.
My 4 - 275w panels are wired series/parallel giving me +< 70 voc.
My charge controller reads 2.1 - 4.1 amps in the battery and I'm confused. I would have thought this battery bank could handle this light load but at this moment, 1 hour after direct sunlight is off panels, my battery level meters are saying 79/81%, and dropping.
I don't want to go below 50% as I don't see the battery making it through the night, thus system shutting down.
What can I try?
Thanks
Should I be trying to muster more amps?
Thanks again?
They're in series/parallel
400bird
Solar Wizard
What was the battery voltage when you took this 4 amps measurement?
With 1100 watts of panels, you should be more in the 40 amp range.
What is your charge controller?
Ampster
Renewable Energy Hobbyist
That refrigerator load is 1700 Watts which is the equivalent to 70 Amps at 24 volts.
400bird
Solar Wizard
I really hoped that was the peak rating. My full size fridge doesn't come near that when running.
Ampster
Renewable Energy Hobbyist
I would hope so. Whatever it is, it is going to be more than double the Amps out of the 24 volt battery.
RCinFLA
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What is this battery level meter. If it is a cheapo that uses battery voltage to determine % used, throw it away and get a Columb (amp-secs) tallying battery monitor. A real battery capacity monitor keeps a running tally of incremental charge and discharge amps verses time and compares the tally against what you put in for battery AH capacity for its % used readout.
You can get a relatively low cost unit like a Juntek battery monitor. Cheap Chinese unit but it works okay.
I felt that the low amp reading was off as well which is the reason for my initial question. The voltage was at 100%. I'm wired @ series/parallel.
The SCC is a 100 amp PowMr.
A series of events led me down a path of purchases I probably should have avoided. I found on CL, 5 - 275W solar panels and 100' of connector wire with mc4 ends, for cheap. No knowing or realizing the their configuration will be akin to 24v.
So I went headlong into the unknown purchasing a 24v inverter and the mentioned controller.
I also bought the batteries and spent the better part of two months designing, building, wiring and finalizing it all together.
I learned a few things and ordered a 60 amp controller only to find that the connect bays were designed for 4awg and all my wiring is #2awg.
I could go on and on but my panels (sticker) show 8+ amps which means something ain't jivin'!
If you can find the time I'll appreciate any feed back.
Thanks
Attachments
Maybe coming from dragon country it's a misprint. The yellow sticker is on the front of the freezer. Does this help with the correct parameters on the unit?
Attachments
Actually 1 is a cheapo 2 the inverter and the SCC both have meters as well and all are within a mean range. Kinda like triangulating with good results.
I will look into the "Junktek" though.
Thanks my friend.
schmism
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mikefitz
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Your fridge claims to have an average power consumption of 30 watts per hour, this is typical of a small unit.
With inverter continious current draw, even with no load, the 2 to 4 amp reading seems correct, taking to account Inverter efficiency .
The SOC , battery level meters, readings you are concerned about are inacurate values based on voltage alone.
Ensure you have the correct charge voltage settings , absorbtion or boost, for your batteries , needs will be in the region of 29.4 volts.
In the evening after a full charge the voltage, with no load will fall to just over 25 volts. As the batteries are discharged regard 24 volts as as a safe limit.
When the batteries are charging the current into the batteries will fall to a low value as the batteries reach full charge, even with lots of solar. When fully charged the current will fall below 4 amps.
Note that the inverter stand by power will be contioious even with the fridge off, ( the fridge thermostat will have a duty cycle typically 35% on time). So with a guess of average power, fridge plus inverter of 60 watts hours, and 6000 usable watt hours in the battery, you have100 hours of operation to get to 50% discharge.
Mike
With inverter continious current draw, even with no load, the 2 to 4 amp reading seems correct, taking to account Inverter efficiency .
The SOC , battery level meters, readings you are concerned about are inacurate values based on voltage alone.
Ensure you have the correct charge voltage settings , absorbtion or boost, for your batteries , needs will be in the region of 29.4 volts.
In the evening after a full charge the voltage, with no load will fall to just over 25 volts. As the batteries are discharged regard 24 volts as as a safe limit.
When the batteries are charging the current into the batteries will fall to a low value as the batteries reach full charge, even with lots of solar. When fully charged the current will fall below 4 amps.
Note that the inverter stand by power will be contioious even with the fridge off, ( the fridge thermostat will have a duty cycle typically 35% on time). So with a guess of average power, fridge plus inverter of 60 watts hours, and 6000 usable watt hours in the battery, you have100 hours of operation to get to 50% discharge.
Mike
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Goboatingnow
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Err the fridge spec say 138 w. There’s no information as to the duty cycle.
So going on that information, that’s approx 6A at 24v assuming invertor efficiency of 90% that’s 156Ah over 24 hours.
Given your bank has around 115Ah to 50% on the face of these numbers you’d need the nearly double the bank or provide sufficient recharging resources during the 24 hour period
So going on that information, that’s approx 6A at 24v assuming invertor efficiency of 90% that’s 156Ah over 24 hours.
Given your bank has around 115Ah to 50% on the face of these numbers you’d need the nearly double the bank or provide sufficient recharging resources during the 24 hour period
