In my 8511+ manual there is a paragraph about setting it up:
Remote sensing
Remote sensing is used to counteract the effect of lead resistance. For example, if you
connect a power supply to the DC Load, the voltage at the power supply's terminals will
not be the same as the voltage at the DC Load's terminals if there is a current flowing
because of the finite resistance from the wires. Using remote sensing, you can sense
the voltage at the power supply's terminals, effectively removing the effect of the voltage
drop in the connection wire.
When using remote sensing, the power displayed by the instrument includes both the
power dissipated inside the instrument and the power dissipated in the leads from the
power supply to the DC Load's input terminals.
Steps to enable remote sensing in the menu:
?1? Press (Shift)+ 9 key into the menu
?2? VFD displays >CONFIG, press Enter key to confirm
?3? Press to choose> SENSE, press Enter key to confirm
(4) Press to choose>ON, press Enter key to confirm, then remote sense function has
been set,and VFD display Sense indicator.
Remote Sensing: SENSE (+) and SENSE (–) are the remote sensing inputs. By
eliminating the effect of the inevitable voltage drop in the DC load leads, remote sensing
provides greater accuracy by allowing the DC load to regulate directly at the source's
output terminals.