Here is my guess.
Pins 4 & 5 are not used, hence no connection (N.C)
Pins 6, 7 are most likely used for romote on/off. If not used a jumper would be connected between pins 6 & 7.
Pins 8 & 15 are sense lines.
May be used in case there is too much voltage drop to your load. If you can drive a load without the use of Pins 8 & 15 then you don't need to connect anything to it.
This link may help... http://www.power-factor-1st.com/uplo...oting-tips.pdf
You didn't say what power supply you were using so I couldn't look for it.