Step 15 (3/3): Insert the RPR220 optical sensor into the terminal block CAUTION: Identifying which legs are which is tricky, so please take care with this step! If in doubt, don’t be afraid to ask us to check the position before you tighten it in place.
On one side of the black plastic body, the upper edge is slightly sloped and “RPR220” is written on it (you need to look carefully). The two legs on this side of the device should both be inserted into the top side of terminal 1.
Of the remaining two legs, the one closest to the chamfered (flattened) corner edge of the black plastic body is inserted into the top side of terminal 2.
The final leg is inserted into the top side of terminal 3.