My off grid solar system was designed by an EE and professionally installed about 8 and half years ago. I bought the property 4 years ago so have no direct knowledge about the installation.
It consisted of 16x80W PV panels, a Xantrex C40 PWM controller, 16 Trojan T105 batteries in two strings of 8 in series connected in parallel, giving some 450Ahours C20 at 48V.
It supplies a small home with two adult occupants who are careful consumers of electricity. We did a power use audit when we moved in 4 years ago and calculated a daily use of 80 amps. Thus we were slightly undersized (80 x 3 = 240, thus 480 amp hours required) but compensated by only using things like vacuum cleaner, washing machine, toaster, hair dryer and similar items during the day when the sun was shining brightly.
The battery cables are shared both by the controller input to battery and out to the inverter. The cabling from the PV are 8mm thick, with both negative and positive cables running directly to the controller - the positive cable runs to the controller through a fuse. The cabling from the batteries are 15mm thick, the negative lead goes to a fuse, and then to a bus bar. 8mm cables go from the bus bar to the controller and to the inverter.
The battery positive cable goes to a 100amp shunt, from which 8mm cables go to controller and inverter. There is another fuse on the input to the inverter.
We have just replaced the battery bank and the controller after 8 years and 3 months of service.
New Batteries are eight 12V 290Ahr AGM, connected in two strings of 4 connected in parallel giving 48V and 580 Ahrs at C20.
New controller is an eTracer 60amp MPPT controller.
They were installed by a registered electrician who followed the old wiring/cable configuration.
Doing some research on other matters, I found that perhaps this is not ideal! It seems the cabling from the controller to the battery bank should be totally separate from the cabling from battery to Inverter.
I would appreciate comments from those more experienced than I in these things. If in fact I do need to change the cabling, do I connect Controller and inverter cables to the same battery terminals, or to terminals at opposite ends of the battery bank?
Thanks in advance, Sub.
It consisted of 16x80W PV panels, a Xantrex C40 PWM controller, 16 Trojan T105 batteries in two strings of 8 in series connected in parallel, giving some 450Ahours C20 at 48V.
It supplies a small home with two adult occupants who are careful consumers of electricity. We did a power use audit when we moved in 4 years ago and calculated a daily use of 80 amps. Thus we were slightly undersized (80 x 3 = 240, thus 480 amp hours required) but compensated by only using things like vacuum cleaner, washing machine, toaster, hair dryer and similar items during the day when the sun was shining brightly.
The battery cables are shared both by the controller input to battery and out to the inverter. The cabling from the PV are 8mm thick, with both negative and positive cables running directly to the controller - the positive cable runs to the controller through a fuse. The cabling from the batteries are 15mm thick, the negative lead goes to a fuse, and then to a bus bar. 8mm cables go from the bus bar to the controller and to the inverter.
The battery positive cable goes to a 100amp shunt, from which 8mm cables go to controller and inverter. There is another fuse on the input to the inverter.
We have just replaced the battery bank and the controller after 8 years and 3 months of service.
New Batteries are eight 12V 290Ahr AGM, connected in two strings of 4 connected in parallel giving 48V and 580 Ahrs at C20.
New controller is an eTracer 60amp MPPT controller.
They were installed by a registered electrician who followed the old wiring/cable configuration.
Doing some research on other matters, I found that perhaps this is not ideal! It seems the cabling from the controller to the battery bank should be totally separate from the cabling from battery to Inverter.
I would appreciate comments from those more experienced than I in these things. If in fact I do need to change the cabling, do I connect Controller and inverter cables to the same battery terminals, or to terminals at opposite ends of the battery bank?
Thanks in advance, Sub.
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