Electronics

Loadpins can be supplied with integrated electronics or as passive sensors with strain gauge bridge. The “Electrics” section is intended for loadpins with integrated electronics only.

Thanks to a digital filter, the integrated electronics have a stable, low noise, zero point stable output signal, particularly at low frequencies of 5 to 105 Hz. The resolution on the analogue output is 4096 parts.

Configuration of loadpin electronics

The load pin with integrated amplifier supplies an analogue output signal of -10.0 V to +10.0 V or of 4-20mA. The display in the unloaded condition can be combined with the tare function (Tara) at 0.0 V or 4 mA, or to other factory preset values.

If both compression loading and tensile loading are displayed, a voltage output of ±10V is recommended.

Tare function (tara)

Applying a control pulse to the “tara” input automatically synchronizes the output signal to 0.0 V or 4 mA. The control pulse must be high for at least 1s, then low for at least 100 ms

Please note: no high signal must remain on the tara input when you switch on.

Scaling function (scale)

The loadpin is available with a scaling function as an option. Owing to a high level on the “scale input”, the measuring signal that is currently applied is scaled to 10.0 V (20mA).

Prior to the scale function being activated, the tara must be applied.

Procedure: the sensor is subjected to a mechanical stress at 100% of the load. Applying a control pulse to the “Scale” input automatically synchronizes the output signal to 10.0V. The control pulse must be high for at least 5s, then low for at least 100 ms.

Please note: when switching on, no high signal must be present on the scale input.

Configuring the scale function (Setup mode 1)

The end value can also be scaled at less than 100% of maximum load.

The proportion of the calibration load on the maximum load can be set in Setup Mode 1 in increments of 5%.

Procedure:

1. Switch off operating voltage;
2. Create the scale input(grey) on the operating voltage(high potential);
3. Switch on operating voltage:
4. Disconnect the scale input from the operating voltage(high potential) – (Setup mode 1 is now active).
5. Re-applying the high potential to the scale input (for 2s) raises the threshold by 5%.Applying the high potential to the tara input (for 2s) lowers the threshold by 5%.The output signal now shows the voltage that will be displayed after the scale function has been activated.Example: If a voltage of 1.0 V is applied to the output (in Setup mode 1), calibrate to 10% of maximum load.If a voltage of 9.0 V is applied to the output (in Setup mode 1), calibrate to 90% of maximum load.
6. Switch off operating voltage;
7. Switch on operating voltage. The measurement amplifier is now back in normal operating mode..

Threshold (open collector)

The threshold switch reacts when the threshold is crossed. The threshold set in delivery condition is 90% of the measuring range. Above 90% of the measuring range, the threshold output is switched to earth. If elongation falls below 88%, the output switches to high impedance.

Configuring the threshold function (Setup mode 2)

The threshold switch of the threshold can be set in increments of 5%.

Procedure:

1. Switch off operating voltage;
2. Create the tara input on the operating voltage (high potential);
3. Switch on operating voltage:
4. Disconnect the tara input from the operating voltage (high potential); (Setup mode 2 is now active).
5. Re-applying the high potential to the scale input raises the threshold by 5%. Applying the high potential to the tara input lowers the threshold by 5%. In Setup mode 2, the output signal show the voltage at which the threshold will be triggered.Example: If you see an output voltage of 1.0 V on the output, the threshold value will be triggered at 10% of the maximum load and reset again at 8%.  If you see an output voltage of 9V on the output, the threshold value will be triggered at 90% of the maximum load.
6. Switch off operating voltage
7. Switch on operating voltage. The measurement amplifier is now back in normal operating mode.

Safety instructions

All safety instructions must be observed during assembly, commissioning and operation of the loadpin. Only appropriately qualified personnel must be allowed to work with the loadpin. Failure to comply with the safety instructions may lead to serious injury and/or material damage. Before commissioning, please check to ensure that the load pin is suitable for your application. The instructions given in this document and on the test certificate must be observed.