help with connections please

[pmitch1400]

i bought two 50 volt 250 watt new solar panels at a garage sale they were still in the boxes, and on opening the junction boxes i find that there is no connection terminals only five buss wires from the cells. i have tried a meter on the wires and get different voltages ranging from around 12-13 volts to 52 volts how should i connect this to my system. i emailed the manufacturer but no response if anyone could help i would be much obliged. thanks Peter




the make is Ningbo Solar Electric Company

[inetdog]

i bought two 50 volt 250 watt new solar panels at a garage sale they were still in the boxes, and on opening the junction boxes i find that there is no connection terminals only five buss wires from the cells. i have tried a meter on the wires and get different voltages ranging from around 12-13 volts to 52 volts how should i connect this to my system. i emailed the manufacturer but no response if anyone could help i would be much obliged. thanks Peter




the make is Ningbo Solar Electric Company

You should find that the five bus wires consist of the two ends of the series string of cells and three wires connected at equally spaced positions along the string. This allows you to connect bypass diodes in four places to limit the loss of power from the panel when only some of the cells are shaded.
It is much more common to just have one or two center tap leads rather than three, but unless one of the five buss wires is actually a panel ground, that is what you have.
Note that 13 times 4 is 52.

The only way you can connect one panel is to run the + and - leads to an MPPT controller to charge batteries or possibly to a micro-inverter if you want to go grid-tied. You should install bypass diodes in a connection box attached to the panel.
You can either connect the two panels in series to get 100V or in parallel to get twice the amps at 50V. What you do there will depend on what you are going to connect them to.

[pmitch1400]

help with connections

You should find that the five bus wires consist of the two ends of the series string of cells and three wires connected at equally spaced positions along the string. This allows you to connect bypass diodes in four places to limit the loss of power from the panel when only some of the cells are shaded.
It is much more common to just have one or two center tap leads rather than three, but unless one of the five buss wires is actually a panel ground, that is what you have.
Note that 13 times 4 is 52.

The only way you can connect one panel is to run the + and - leads to an MPPT controller to charge batteries or possibly to a micro-inverter if you want to go grid-tied. You should install bypass diodes in a connection box attached to the panel.
You can either connect the two panels in series to get 100V or in parallel to get twice the amps at 50V. What you do there will depend on what you are going to connect them to.

Thanks for the reply INETDOG, i am sure glad that someone can help as the makers are obviously not interested anymore .