Weighing Indicator

The weighing indicator is the part that turns the signal from the load cells into a number. It supplies the excitation the cells need, reads their small output, and applies the settings the site works with: capacity and division, zero and tare, hold, accumulation, and over/under or accept limits where a decision has to be made at the scale. The cells and the mechanical build set the real load range, and the indicator scales that signal, so the two are best chosen as one combination rather than separately.

On the sensor side, note how many cells feed the indicator and whether they arrive through a junction box, the signal range and excitation the cells expect, whether the wiring is four-wire or six-wire, and how long the cable run is between the cells and the indicator. A long run or a cable routed beside power lines is a common reason a reading drifts or jumps, and no keypad setting fixes that.

Then the human side. Decide how large the digits must be and whether they have to be read indoors, outdoors or under a canopy; which keys the operator actually needs, such as tare, zero, print and preset; and how quickly a stable reading has to appear after a load is placed. Outputs belong here too: serial or another connection to a printer, a computer, a PLC or a remote display, and setpoint contacts to drive a lamp, a valve or a buzzer. Finally, the supply available where the indicator sits and the way it is mounted: panel, desk, column or cabinet, sealed or open to a dry area.

When an indicator is replaced, the old settings are the specification to record: capacity, division, cell sensitivity, connection type, the outputs in use and any notes from the last calibration. Every one of those settings affects the whole system, so it is worth writing them down while the old unit is still connected.