ADC fault or ADC fail

ADC fault or ADC fail

The “A to D” fault means that two identical Analogue to Digital conversions produced the same count number. Normally this would be impossible unless the Analogue to Digital (A to D) converter is faulty or the voltage readings from the scale base is outside the range of the A to D converter.

Corrective actions

Disconnect the load cell cable from the back of the indicator, turn the indicator off and back on again. Does the A to D fault go away? Try connecting the operator panel to another scale base and check for the A to D fault message. If the Operator panel works with another scale base, without faulting with “A to D fault”, then this indicates that the signal voltage from the scale base is outside the A to D range.

If the fault is traced to the scale base as described above, then check that the load cell cable from the operator panel to scale base junction box is not cut or crushed (a crushed cable can cause the internal wires to short out).  Swapping this cable between scale bases can be used to check the cable if suspected.

Also check that no wires have been caught between the edge of the metal junction box and the scale frame causing a short circuit.  Also measure the voltage between the green and white wires (signal wires for the four load cells), which voltage should not be greater than 10 mV.

    • Related Articles

    • Screen shows ADC 2 error

      This is usually a short circuit in the load cell cable, or an internal problem in the trimmer box. If the input signal from the load cells is shorted to the excitation voltage, then the scale will first read "Heavy Bag", then display the message "ADC ...
    • "Error Data Nil" message

      The "Error Data Nil" message on the passenger panel means that power is applied, but no RS-485 data is received at the passenger panel. The centre two pins of the connector and cable are used for the communications. This issue can be associated with ...
    • Passenger panel shows "Err Char Bad"

      The data being sent from the operator panel is corrupted and the passenger panel is reporting the error as “Bad Char” or bad character received. There are no settings that could be wrong that will produce this error, and you will need to confirm if ...
    • "Bad addr" message on passenger panel

      The command from the operator panel has a standardised format that includes an address byte. The message on the passenger panel indicates that the format received is unexpected. The fault could be with the operator panel, load cell cable or the ...
    • Weight reading is drifting

      Confirm that this happens when a weight is placed on the scale and not touched, and nobody is moving around the scales (movement of the floor/desk can be transmitted to the scale if these are touching the scale, which will appear as if the weight ...