Optima G4 eith Reson8?

Hi,
I am about to fit a Reson8 to a Accenta G4 mini panel, I have noticed that the panel has 6 wires for the external bell box but the Reson8 only has a 5 wire connection strip

T RTN
D + Hold Off
A - Hold Off
B Trig
- STB

Do I need the + strobe connecting to anything in the control Panel?

Thanks for any help supplied.