Inverter Voltage Drop (Overload)

[Rich.M]

Originally Posted by babock

If you look at the Trojan T-105 spec, they show a chart where the battery is being discharged at 250A. Not sure where you got this 25% number.

http://www.trojanbattery.com/pdf/dat...ata_Sheets.pdf

Looking at the same data sheet, those batteries can only offer 85% of rated power below 60 degrees. The op had been in Wall SD, nights are below 60. Factor in the overnight use of 25-75 amphours ( depends on tv, heater etc ) and those batteries may have been down to 50-65% of capacity in the am and cold. 2 batteries just can't make that demand in that state. The batteries are also not Trojans, the gold standard.

[babock]

I was just pointing out that the other poster said you could only discharge at a rate of 25% of the capacity which is a totally incorrect statement.

[camaraderie]

Originally Posted by babock

I was just pointing out that the other poster said you could only discharge at a rate of 25% of the capacity which is a totally incorrect statement.

BTW...one of VonWentzels battery pages state: "Gel and Absorbed Glass Mat (AGM) batteries can dispense charge at a higher rate than flooded cells due to their lower Peukerts exponent. "Deep-cycle Flooded Cells cannot deliver more than 25% of their rated amp-hour capacity in amps without plummeting Available Capacity. "
Battery Types: Flooded versus AGM and Gel

This would account for the shut down of the inverter as the voltage plummets ...but you are correct that the battery itself can deliver more than 25% it appears. The question remains...how much and what is the "damage point"? Hopefully Trojan will clarify for me.

[dmdomokos]

Originally Posted by camaraderie

BTW...one of VonWentzels battery pages state: "Gel and Absorbed Glass Mat (AGM) batteries can dispense charge at a higher rate than flooded cells due to their lower Peukerts exponent. "Deep-cycle Flooded Cells cannot deliver more than 25% of their rated amp-hour capacity in amps without plummeting Available Capacity. "
Battery Types: Flooded versus AGM and Gel

This would account for the shut down of the inverter as the voltage plummets ...but you are correct that the battery itself can deliver more than 25% it appears. The question remains...how much and what is the "damage point"? Hopefully Trojan will clarify for me.

Wow, great reading. I guess I should have sprung for those Lifeline AGM batteries if I'm making drip coffee for the DW.

[camaraderie]

Originally Posted by camaraderie

BTW...one of VonWentzels battery pages state: "Gel and Absorbed Glass Mat (AGM) batteries can dispense charge at a higher rate than flooded cells due to their lower Peukerts exponent. "Deep-cycle Flooded Cells cannot deliver more than 25% of their rated amp-hour capacity in amps without plummeting Available Capacity. "
Battery Types: Flooded versus AGM and Gel

...This would account for the shut down of the inverter as the voltage plummets ...but you are correct that the battery itself can deliver more than 25% it appears. The question remains...how much and what is the "damage point"? Hopefully Trojan will clarify for me.

@ Babock...Damn...apparently my prior reply to you went off in the ether somewhere. What I said in summary was THANKS for pointing that chart out as it indeed shows way more than 25%. THEN I also said I have a problem with that chart and will be writing Trojan for clarification. WHY??
Because it shows a 220AH battery (20 hr rate) which delivers 9 amps for 20 hours ....delivering 250 amps for more than an hour. This is patently ridiculous since even tripling the 9 amp draw to 27 amps would reduce total amp hour capacity to around 75 amphours!! (Peukerts law) How are we to believe that increasing the amp draw 25 times to 250amps for an hour or more is possible??? The chart says for estimates only but I'm thinking that is some wild ass estimate!
EDIT Actual # for 250 amp discharge rate after calculating Peukert to be 1.22...is 25 minutes 94 ah based on the Trojan spec sheet supplied data.)

Will let you know if I hear anything back from Trojan but something ain't right. And thanks again as it appears that at the very least...the 25% is easily exceeded BUT not at all advisable.

[jcarlilesiu]

I clearly need too get a volt meter to better monitor my batteries, and a better charger.

Any recommendation?

I would like a flush mount battery monitor of possible to fit it with all my other gauges.