Hi everyone,
I've been dabbling in solar recently to make an offgrid setup.
I have 4 x 'Solar Europa', 36v, 220w panels wired in series to a 'Tracer4215BN', 40a MPPT charge controller. I have a bank of 12 'Varta' 12v, 70ah batteries. The batteries are wired into 6 parallel banks of two batteries (in series), giving one huge 24v, 420ah bank. I've also got a small 'Mercury', 600w modified wave inverter.
I've tested my system for a few weeks now and it's good! I want to expand and develop it further.
What I have noticed is that the inverter is not suitable for my needs because; 1) It is not allowing enough wattage to be drawn, and 2) It needs a to be a sine wave inverter.
This leads me to investigate a few issues:
Upgrading my bank voltage. It's possible for me to upgrade the bank to 48v, although the charge controller doesn't seem to support it. Why though? If it can support 12,24 and 36, why can't it support 48v? If it did support 48v, how would this affect MPPT? MPPT seems to work on higher voltages, so what if my panels were delivering only 32v at some point? the batteries wouldn't charge? Is it even worth me upgrading to 48v?
I want to be able to draw a maximum of 3kw on a very irregular basis, I'd like to be able to draw 50w on a permanent (24/7) basis, and throughout the day time i'd expect to be drawing on average 500w for a few hours. The 3kw idea is for times when both a hoover and a microwave are running simultaneously (very unlikely) and for general future-proofing.
Wiring is not the issue for me; I can get thick cables very cheaply as I have a contact, plus, the inverter will be very close to the battery bank.
One issue for me is that most powerful inverters seem to be 48v, rather than 24v.
I'm looking at some APC UPS units, some are 24v (2.7kw) and some are 48v (4kw).
I guess I'm just a bit lost when it comes to making a decision on the bank voltage for the inverter. Can anyone steer me in the right direction?
Thanks, Antony
Panels:
http://www.renugen.co.uk/content/Solar_Panel_Brochures_part_4/Solar%20Panel%20Brochures%20part%204/solar_europa_brochure/solar_europa_chn220-60p.pdf
Charge Controller:
http://www.epsolarpv.com/en/index.php/Product/pro_content/id/573/am_id/136
I've been dabbling in solar recently to make an offgrid setup.
I have 4 x 'Solar Europa', 36v, 220w panels wired in series to a 'Tracer4215BN', 40a MPPT charge controller. I have a bank of 12 'Varta' 12v, 70ah batteries. The batteries are wired into 6 parallel banks of two batteries (in series), giving one huge 24v, 420ah bank. I've also got a small 'Mercury', 600w modified wave inverter.
I've tested my system for a few weeks now and it's good! I want to expand and develop it further.
What I have noticed is that the inverter is not suitable for my needs because; 1) It is not allowing enough wattage to be drawn, and 2) It needs a to be a sine wave inverter.
This leads me to investigate a few issues:
Upgrading my bank voltage. It's possible for me to upgrade the bank to 48v, although the charge controller doesn't seem to support it. Why though? If it can support 12,24 and 36, why can't it support 48v? If it did support 48v, how would this affect MPPT? MPPT seems to work on higher voltages, so what if my panels were delivering only 32v at some point? the batteries wouldn't charge? Is it even worth me upgrading to 48v?
I want to be able to draw a maximum of 3kw on a very irregular basis, I'd like to be able to draw 50w on a permanent (24/7) basis, and throughout the day time i'd expect to be drawing on average 500w for a few hours. The 3kw idea is for times when both a hoover and a microwave are running simultaneously (very unlikely) and for general future-proofing.
Wiring is not the issue for me; I can get thick cables very cheaply as I have a contact, plus, the inverter will be very close to the battery bank.
One issue for me is that most powerful inverters seem to be 48v, rather than 24v.
I'm looking at some APC UPS units, some are 24v (2.7kw) and some are 48v (4kw).
I guess I'm just a bit lost when it comes to making a decision on the bank voltage for the inverter. Can anyone steer me in the right direction?
Thanks, Antony
Panels:
http://www.renugen.co.uk/content/Solar_Panel_Brochures_part_4/Solar%20Panel%20Brochures%20part%204/solar_europa_brochure/solar_europa_chn220-60p.pdf
Charge Controller:
http://www.epsolarpv.com/en/index.php/Product/pro_content/id/573/am_id/136
