I take it that the pedal is a midi pedal and that the rack unit converts midi into analogue switching, right? To switch amps like a Boogie via midi.
If it is such a unit, you can use the (midi) pedal - no need for the rack thing. Herbert speaks midi.
With which kind of cable the pedal is hooked to the rack unit?
A pic would help too - or the "name" of your pedal/unit.