Module poly SILIKEN 220w/30v

Re: Module poly SILIKEN 220w/30v

Can these panels wired in 2 series outputting a voltage of 60v, but an open circuit voltage of nearly 80v -
match without problem with the regulator OUTBACK MX60?  http://www.siliken.com/pdf/Cat-ing/SLK60P6L-221-in.pdf

Jacques,

The MX60 can handle these two PV modules in series with no problem. What voltage battery bank are you planning?

Regards,
Jim / crewzer

Re: Module poly SILIKEN 220w/30v

Jacques,

The voltage output from two SLK60P6L modules connected in series will be 59.4 Vmp STC and 73.6 Voc STC. The MX60 can handle these input voltages under virtually any environmental conditions.

The voltage output from two Kaneca 60 W modules connected in series will be 134 Vmp and 183.6 Voc. The Voc is way above the MX60’s “suspend operation” limit of ~140 V, and it’s also above the MX’ documented absolute limit of 150 V.

Thank you for the battery voltage information. Unfortunately, I believe that a system consisting of a PV array rated at 59.4 V STC and a “48 V” battery bank will not work particularly well in your environment (Spain = warm and hot). The 48 V battery bank will typically need a charging voltage of between ~56 V (gel) and 59.2 V – 62 V (flooded-cell) to recharge at ~25 C.

PV module output voltage drops as the abmbient (and cell) temerature increases. Accordingly, the typical mid-day output voltage from two SLK60P6L modules connected in series will likely be in the 50 V to 55 V range with the controller operating in BULK / MPPT mode in your location. This is too low the meet the charging voltage requirements described above.

Unless you live in a cold part of Spain (is there such a place?), I recommend you consider connecting three SLK60P6L modules in series to the MX. The controller will down convert the ~80 V to the correct “48 V” charging voltage. The “extra” voltage will (mostly) be converted to additional charging current.

Finally, note that for every 100 Ah of 48 V battery capacity, you’ll need ~400 W STC of PV.

HTH,
Jim / crewzer

Re: Module poly SILIKEN 220w/30v

Jacques,

I believe the KANEKA's warm/hot weather output voltage may be too low to charge a 48 V battery bank. I also believe that connecting three Siliken modules in series would be very, very low risk -- if any at all -- in Spain.

A single Siliken's Voc is 36.8 V, so three in series would be 36.8 V x 3 = 110.4 V. The margin of safety between 110.4 V and the MX' "suspend operation" spec of 140.5 V is ~30 V, or ~27% of 110.4 V. Allowing for a temperature coefficient of -0.5%/C, the PV modules' cell temperature could drop to 25 C - 54 C = -29C (-20 F) before the Voc became a problem. Does your location reach -29 C on winter mornings? The Siliken's actual specs are even more conservative, which should permit an even greater temerature operating range.

The decision is ultimately yours to make, but I think you'll be unhappy with the Kaneka, and I think the the "three Siliken" arrangement will work fine.

Good Luck to you!
Jim / crewzer

Re: Module poly SILIKEN 220w/30v

niel,

No problem. A 100 W STC array can realistically supply ~5.5 A or so to a "12 V" battery, so that makes it a good match for a 12 V battery bank rated at ~100Ah. For a "48 V" battery bank, you'd need a PV array 4 X as large. So, ~400 W per 100 Ah at 48 V. YMMV.

HTH,
Jim / crewzer