Solar Charges confusion

drfhm · 01-22-17, 07:24 AM

14 years ago I installed an off grid solar system that has worked well for me , I had 600amp/hrs of Trojan batteries and my consumption has always been between 2000 and 2500 watt/hours every 24 hours split fairly evenly between the day time charging and night with no charge coming in . My batteries are fully charged by midday when the suns out and both my Solener ( good quaity Spanish make ) and Morning Star controllers ( both good quality and lasted 14 years so far without issue as I double check everything regularly with a multimeter ) float at 28.8 volts , I am assuming I am only taking about 25% at most from my battery bank ( 2500watts / 25v = 100amp/hrs , 600 / 100 = 15% + a generous allowance for anything not accounted for , equipment self use etc ) ( please correct me if I have that wrong as 2000-02500 watts is the cumulative total shown each day on my Solener 1.5kw watt inverter ) . The batteries have lasted 8 years showing no sign of failing however now winters here they are dropping to low late at night if they haven't had a full charge in the daytime so I have replaced them with 600 amp/hr Rolls 4 x 6v ( S605 ) I raised the SG to 1.280 after standing 24 hours as required when I first received and replaced my Trojans batteries with them but now after 10 days that has dropped to 1.21 , have not been able to get the SG of these batteries back up to the required figure , they remain around 1.20 -1.21 ( 10c ) Rolls have told me I need a Bulk/Absorption charge of 29.8 and a float volt of 27.6 which is greater than my present charge controllers can supply so I have looked to replace the 2 x 30amp ones with a single 65amp one and have found two reasonably priced ones that allow adjustment only of the Float voltage up to 26-30 volts , neither give the Bulk/Absorption figures which don't have any adjustment and the sellers have no idea either and the manufacturers can only supply the manuals which don't give it either which to me seems silly as I would have expected them to be an important factor , they have adjustable load parameters but are of no interest to me as I never take anything direct of them . I wish now I had looked an the charging voltages required for the Rolls batteries as seeing they are higher than I would have expected I would not have bought them , I expected considering they are not cheap to be compatible with other deep cycle batteries .My panel array is 1020 watts at 24 volts and when the sun is out which here in Spain is a good deal of the time the charge controllers show an input between them of 30 – 50 amps . Any advice which doesn't involve a large outlay for expensive controllers would be very much appreciated .

creeky · 01-22-17, 11:16 AM

Quote:

Originally Posted by drfhm

Morning Star controller.

Which model controller do you have? The Morningstar often receive firmware updates that can be applied. And allow for different settings. Check the morninstar website for the latest software/firmware.

You might be able to use the ms controllers after all.

Goodluck.

drfhm · 01-22-17, 12:24 PM

Prostar PS30 , as i said its 14 years old so although been good value for the money over the time i have had it and its shows no sign what so ever of failing it simply is not suitable for my new batteries . On the off chance i took your advice and checked the website and although they still sell them they are many times more expensive than comparable ones and haven't change at all , still pre set Voltages with no adjustments on anything at all .

creeky · 01-22-17, 01:09 PM

The flooded cell voltages on the 30 are pretty close.

The float is 27.4. The absorb is 28.8. The equalize is 29.8/30.2.

You could (should?) run your batteries on the equalize cycle. A good quick fix to get your SG back up.

But it's true. You're at 1kw of solar panels. So maybe that is time to get mppt working for you. Though. As you say, you're fully recharged by noon. So pwm is doing it okay for you.

One ts-60 would do you. That controller is programmable. So you can put in your charge absorb, float and equalize settings. I programmed my mppt to lithium. that was nice.

Lots of good chinese controllers now too. And the european Victron is pretty nice. Cheap too.

drfhm · 01-22-17, 01:40 PM

I contacted Rolls and i will copy and paste their reply , i gave them the same info , all the charge settings for the batteries are higher than other batteries i have used for myself and from looking at friends systems and batteries , Rolls need 30.6v Bulk/Absorption but for some reason their tech guy said 29.8v from a charge controler which is .8v less than the manual ( S-605 ) , dont know why , strange , lastly 31.8 equalization , as you say the float voltage is close enough 27.6v and my controllers Float at 27.4v.

Reading through the below email string, it would appear that the charge voltages are a little low and the size of the charger is a little small .

Solar Controller:

Bulk / Absorption: 29.8V

Charger (or Charger / Inverter):

Bulk / Absorption: 30.60V
Charger Current: 50A
Absorption time: 4 hours
Equalisation: 31.8V
Equalisation time: 2.5 hours

I will look at the ones you suggested .

creeky · 01-22-17, 01:56 PM

Those are some pretty high numbers eh.

So at least you can run the two controllers you have now on equalize daily. 30.2. Just to get you to the time you put in a new controller.

Then run a real equalize to desulphate the batteries after you put in the new controller.

jjackstone · 01-22-17, 03:53 PM

Is there any chance at all that you are using more power than you think?
JJ

drfhm · 01-22-17, 04:09 PM

Nope , my inverter tracks total use and i zero it every morning at 8pm . I only have 7 pieces of equipment and it was a simple calculation to work out my consumption which matches the figures the inverter gives . There is no question that my controllers pass through more than i consume to the batteries and they used to be replenished by midday but that was with Trojan batteries which required charging within the parameters of the controllers i have now . The Rolls ones wont because they require more voltage although every morning before i get any charge coming in and after resting for 7 hours with only the inverters 26watt draw Im always getting a voltage in them of 24 - 24.3 . Have made the decision tonight that in the morning i will order the TS-60 as i think it will allow the adjustment of Bulk/Absorption and Float to suite the batteries as well as a few other useful tweaks such as forced Equalization however i have only skipped through the manual .

Fingers crossed

01-22-17, 07:24 AM	#1
drfhm Lurking Renovator Join Date: Jan 2017 Location: spain Posts: 4 Thanks: 0 Thanked 0 Times in 0 Posts	Solar Charges confusion 14 years ago I installed an off grid solar system that has worked well for me , I had 600amp/hrs of Trojan batteries and my consumption has always been between 2000 and 2500 watt/hours every 24 hours split fairly evenly between the day time charging and night with no charge coming in . My batteries are fully charged by midday when the suns out and both my Solener ( good quaity Spanish make ) and Morning Star controllers ( both good quality and lasted 14 years so far without issue as I double check everything regularly with a multimeter ) float at 28.8 volts , I am assuming I am only taking about 25% at most from my battery bank ( 2500watts / 25v = 100amp/hrs , 600 / 100 = 15% + a generous allowance for anything not accounted for , equipment self use etc ) ( please correct me if I have that wrong as 2000-02500 watts is the cumulative total shown each day on my Solener 1.5kw watt inverter ) . The batteries have lasted 8 years showing no sign of failing however now winters here they are dropping to low late at night if they haven't had a full charge in the daytime so I have replaced them with 600 amp/hr Rolls 4 x 6v ( S605 ) I raised the SG to 1.280 after standing 24 hours as required when I first received and replaced my Trojans batteries with them but now after 10 days that has dropped to 1.21 , have not been able to get the SG of these batteries back up to the required figure , they remain around 1.20 -1.21 ( 10c ) Rolls have told me I need a Bulk/Absorption charge of 29.8 and a float volt of 27.6 which is greater than my present charge controllers can supply so I have looked to replace the 2 x 30amp ones with a single 65amp one and have found two reasonably priced ones that allow adjustment only of the Float voltage up to 26-30 volts , neither give the Bulk/Absorption figures which don't have any adjustment and the sellers have no idea either and the manufacturers can only supply the manuals which don't give it either which to me seems silly as I would have expected them to be an important factor , they have adjustable load parameters but are of no interest to me as I never take anything direct of them . I wish now I had looked an the charging voltages required for the Rolls batteries as seeing they are higher than I would have expected I would not have bought them , I expected considering they are not cheap to be compatible with other deep cycle batteries .My panel array is 1020 watts at 24 volts and when the sun is out which here in Spain is a good deal of the time the charge controllers show an input between them of 30 – 50 amps . Any advice which doesn't involve a large outlay for expensive controllers would be very much appreciated .

01-22-17, 12:24 PM	#3
drfhm Lurking Renovator Join Date: Jan 2017 Location: spain Posts: 4 Thanks: 0 Thanked 0 Times in 0 Posts	Thank you for your reply Prostar PS30 , as i said its 14 years old so although been good value for the money over the time i have had it and its shows no sign what so ever of failing it simply is not suitable for my new batteries . On the off chance i took your advice and checked the website and although they still sell them they are many times more expensive than comparable ones and haven't change at all , still pre set Voltages with no adjustments on anything at all .

01-22-17, 01:09 PM	#4
creeky Journeyman EcoRenovator Join Date: Jun 2011 Location: a field somewhere Posts: 304 Thanks: 64 Thanked 44 Times in 31 Posts	The flooded cell voltages on the 30 are pretty close. The float is 27.4. The absorb is 28.8. The equalize is 29.8/30.2. You could (should?) run your batteries on the equalize cycle. A good quick fix to get your SG back up. But it's true. You're at 1kw of solar panels. So maybe that is time to get mppt working for you. Though. As you say, you're fully recharged by noon. So pwm is doing it okay for you. One ts-60 would do you. That controller is programmable. So you can put in your charge absorb, float and equalize settings. I programmed my mppt to lithium. that was nice. Lots of good chinese controllers now too. And the european Victron is pretty nice. Cheap too. __________________ Current projects Chevy Volt battery pack conversion To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. Blog that is down right now but will return To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. Business where I sell solar stuff [url]https://www.bobolinksolar.com

01-22-17, 01:56 PM	#6
creeky Journeyman EcoRenovator Join Date: Jun 2011 Location: a field somewhere Posts: 304 Thanks: 64 Thanked 44 Times in 31 Posts	Those are some pretty high numbers eh. So at least you can run the two controllers you have now on equalize daily. 30.2. Just to get you to the time you put in a new controller. Then run a real equalize to desulphate the batteries after you put in the new controller. __________________ Current projects Chevy Volt battery pack conversion To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. Blog that is down right now but will return To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. Business where I sell solar stuff [url]https://www.bobolinksolar.com

01-22-17, 04:09 PM	#8
drfhm Lurking Renovator Join Date: Jan 2017 Location: spain Posts: 4 Thanks: 0 Thanked 0 Times in 0 Posts	Think this is the answer Nope , my inverter tracks total use and i zero it every morning at 8pm . I only have 7 pieces of equipment and it was a simple calculation to work out my consumption which matches the figures the inverter gives . There is no question that my controllers pass through more than i consume to the batteries and they used to be replenished by midday but that was with Trojan batteries which required charging within the parameters of the controllers i have now . The Rolls ones wont because they require more voltage although every morning before i get any charge coming in and after resting for 7 hours with only the inverters 26watt draw Im always getting a voltage in them of 24 - 24.3 . Have made the decision tonight that in the morning i will order the TS-60 as i think it will allow the adjustment of Bulk/Absorption and Float to suite the batteries as well as a few other useful tweaks such as forced Equalization however i have only skipped through the manual . Fingers crossed

01-22-17, 01:40 PM	#5
drfhm Lurking Renovator Join Date: Jan 2017 Location: spain Posts: 4 Thanks: 0 Thanked 0 Times in 0 Posts	I contacted Rolls and i will copy and paste their reply , i gave them the same info , all the charge settings for the batteries are higher than other batteries i have used for myself and from looking at friends systems and batteries , Rolls need 30.6v Bulk/Absorption but for some reason their tech guy said 29.8v from a charge controler which is .8v less than the manual ( S-605 ) , dont know why , strange , lastly 31.8 equalization , as you say the float voltage is close enough 27.6v and my controllers Float at 27.4v. Reading through the below email string, it would appear that the charge voltages are a little low and the size of the charger is a little small . Solar Controller: Bulk / Absorption: 29.8V Charger (or Charger / Inverter): Bulk / Absorption: 30.60V Charger Current: 50A Absorption time: 4 hours Equalisation: 31.8V Equalisation time: 2.5 hours I will look at the ones you suggested .

01-22-17, 03:53 PM	#7
jjackstone Helper EcoRenovator Join Date: Mar 2009 Location: Sacramento,Ca Posts: 88 Thanks: 5 Thanked 32 Times in 23 Posts	Is there any chance at all that you are using more power than you think? JJ