Ground wires for Oracle-Delphi MKIII TT

There are three ground wires running along side of the RCA cable that connects the TT to the preamp. I have one connected to the preamp,where do the the other two connect? Do all three connect to the same post? Thank you.
Where do these wires originate on the turntable? Do you have the separate termination box on this turntable? Basically - with ground wires - you keep attaching them until the hum get's louder - then you take off the last one you attached.Weirdly enough - I've had TT/Pre combo's in the past that had noticeably less hum with the ground wire not attched to anything.These wires/interconnects wouldn't happen to say Discwasher anywhere on the jacket? Discwasher made some early low capacitance interconnects many years ago - that had a ground wire alongside each shielded cable in the pair.
Oracle turntables have a ground connection under the aluminum main chassis - look for a screw terminal there. In some models you can also connect a ground wire to the motor chassis.