Connecting 4 panels in parallel

[donmc512]

Is it acceptable to connect panel 1 and 2 via a MC4 T block (T1), then panel 3 and 4 via a MC4 T block (T2), then connect wire from T1 and T2 via a 3rd T block and cable out of that to the charge controller (about 15-20 ft). Panels are 17.5 v, 4.87 amps. Total length from panel to charge controller about 20-25 ft.

[inetdog]

Is it acceptable to connect panel 1 and 2 via a MC4 T block (T1), then panel 3 and 4 via a MC4 T block (T2), then connect wire from T1 and T2 via a 3rd T block and cable out of that to the charge controller (about 15-20 ft). Panels are 17.5 v, 4.87 amps. Total length from panel to charge controller about 20-25 ft.

It will work electrically, in that the current from the parallel panels will get to the CC. (Assuming you do the same thing on both + and - sides of the panel.)
But it leaves you no place to put a fuse in each individual panel circuit. Does the panel manufacturer specify a maximum series fuse size?

Ideally you would want to use a 5 to 7 amp fuse in series with each panel, to protect a faulty panel from being damaged or ignited by the reverse current from the other three panels. If the manufacturer specifies a maximum series fuse size of 15 amps, you could theoretically put a fuse on the output of T1 and T2, or at the two inputs to T3, but to do that you would have to add some sort of combiner box, taking away the convenience of using T's in the first place.

You will probably be better off connecting all four panels to a fused combiner box, then to the CC. This will also give you a place to connect all of the - leads together.