Load cells (usually strain guages)measure force. They may either have an internal amplifier, or require an external amplifier. An internal, or integral, amplifier may provide advantages such as fewer componenets, lower total cost, and possibly reduced noise, since an unamplified signal that is run to the external conditioner may be more susceptible to noise than an amplified signal.
For load cells with no integral amplifier, the millivolt signal from the load cell must be amplified with a signal conditioner in order to work with the RMC. For best resolution, the signal should be amplified to to ±10 V or 0-10 V, although ±5 V, 0-5 V, and 4-20 mA will work as well.
The bandwidth requirement of the signal conditioner depends on the system it is measuring. Slower systems (those that are large or have compliant loads) can use signal conditioners with bandwidths in the hundreds of Hz. Faster systems will require signal conditioners with bandwidths in the kHz range. If the bandwidth spec is given as a time constant, it should be 1 millisecond (equivalent to 160 Hz) or less, but 160 microseconds (equivalent to 1 kHz) or less is even better.
Delta is aware of the following load cells and signal conditioners that have good bandwidth and work with the RMCs:
- DSCA38 signal conditionar: http://www.dataforth.com/model.view.aspx?modelid=32
p-RELS series load cell, with built-in amplifier: https://www.milwaukeecylinder.com/pdfs/p-rels-series-datasheet.pdf
Built-in amplifier makes wiring nice and easy.
- p-RELS series load cell, with built-in amplifier: https://www.milwaukeecylinder.com/pdfs/p-rels-series-datasheet.pdf
- Load Cells http://www.interfaceforce.com/loadcells.php
- DMA Signal Conditioner
- SGA Signal Conditioner
Other signal conditioners with a bit slower response are available from:
For more details, or to suggest a product to be added to this list, send an email to email@example.com.