Warm up time may have an effect on voltage readings taken from s-type load cells, making prior load- voltage calibration equations inaccurate. PURPOSE: To evaluate the effect of warm up time on load- voltage relationship in s-type load cells. METHODS: Dead weight calibrations were performed on two load cells using 200kg after 15 minutes, 1 hour, and 2 hours of warm up time. A linear model was created to estimate the influence of warm up time on the load-voltage relationship (i.e. voltage = β0 + β1•load + β2•power.source(plug) + β3•time + β4•load • time.) RESULTS: Time did not affect voltage in one testedload cell (i.e. no main (p=0.2396) or interaction effect for load x time (p=0.7492)). In the second load cell, there was a significant interaction effect of load x time (p=0.0079). At 200kg (i.e. the maximum tested load), each minute of additional warm up time would change measured voltage by about -0.00005 volts on average. CONCLUSION: Although time did affect voltage and the load-voltage relationship, the size of the effect may be practically irrelevant.
Phillips, Jherrica; Pulido-Ojeda, Marcus; Kirkpatrick, Mikaela; Landa, Ashley; Martin, Eric; Beckham, George; and Kim, Steven
"Effect of Device Warm-Up Time on Load-Voltage Relationship in S-Type Load Cells,"
International Journal of Exercise Science: Conference Proceedings: Vol. 14:
2, Article 163.
Available at: https://digitalcommons.wku.edu/ijesab/vol14/iss2/163