Remote Sense Connections - Agilent Technologies N8900 series Operating Manual

Connections-Single Unit

Remote Sense Connections

When the sense leads are not connected to the load, the power supply will internally sense the voltage at the output
terminals (referred to as local sensing), which regulates the output voltage at the output terminals. This does not com-
pensate for the load lead voltage drop.
Remote sensing improves the voltage regulation at the load by monitoring the voltage at the load rather than at the
output terminals. This lets the power supply compensate for the voltage drop in the load leads. Remote sensing is use-
ful for CV operation with load impedances that vary or have significant lead resistance. It has no effect during CC oper-
ation. Because sensing is independent of other power supply functions, remote sensing can be used regardless of how
the power supply is programmed.
Equipment Damage Always connect the + sense lead to the + terminal of the load and the -
sense lead to the - terminal of the load. If a sense lead opens during operation the output may
momentarily overshoot.
Connect the unit for remote sensing by connecting the sense leads as close as possible to the load. The power supply
will automatically detect that the remote sense terminals are being used and will compensate for the load lead voltage
drop.
Do NOT bundle the sense wire-pair together with the load wires; keep the load wires and sense wires separate. Keep
the sense wire-pair as short as possible and twist or bundle it to reduce lead inductance and noise pickup.
Note that the sense leads carry only a few milliamperes of current and can be a much lighter gauge than the load
cables. However, note that any voltage drop in the sense leads can degrade the output voltage regulation. Try to keep
the sense lead resistance less than about 0.5 Ω per lead (this requires 20 AWG/1.0 mm 2 or heavier for a 50 foot
length).
32 Agilent N8900 Series Operating and Service Guide