Reviewing Remote Sense Wiring During Load Disconnection

Remote sense compensates voltage drop between a supply and its load, but a removable load introduces states where the power and sense connections may not remain intact together. Review those states before treating the connector as a simple extension of the output terminals.

Draw power and feedback separately

The TDK-Lambda remote sensing explanation describes sensing at the load, the finite compensation range, and local sense connections when remote sensing is unused. The exact supply manual determines the supported wiring and fault behavior.

Draw positive power, return power, positive sense, and negative sense as separate conductors. Include connector contacts, local sense links, fuses, and any fallback resistors specified by the manufacturer.

List partial connection states

Consider either sense conductor open, either power conductor open, and the order in which contacts make or break. Determine what voltage the control circuit sees in each state. Do not assume that an open sense input always falls back to local regulation; that is a device specific feature.

If the load can be disconnected while energized, check whether the connector guarantees a relevant contact sequence. A schematic net name does not establish which physical pin separates first during real handling.

Check compensation and protection limits

Calculate the normal cable drop at maximum load and compare it with the supply’s permitted compensation. The supply terminal voltage rises to make up that drop, so components at the source end may experience a different voltage from the regulated load.

For a hypothetical 1 V total cable drop while maintaining 12 V at the load, the supply terminals need approximately 13 V. This illustrates why the allowed adjustment range and source-end component ratings must be checked together.

Validate fault behavior with a controlled load

Use a suitable dummy load and a reviewed switching fixture to reproduce supported connection events. Monitor voltage at both supply and load, sense pin voltage where accessible, current, and protection status. Begin with bounded conditions that cannot damage the intended product load.

Check restoration as well as disconnection. A supply that enters a protection state may require a specific recovery action, and the reconnection transient can differ from normal startup.

Save the conductor map, contact sequence assumptions, compensation budget, and measured fault response. If remote sense is not used, install the manufacturer’s required local connections. A satisfactory design establishes a defined feedback condition for every supported connection state. Correct voltage with a fully seated connector does not establish acceptable behavior when one thin sense wire or one power contact opens before the others.