Campbell Scientific CR10 CR10 Measurement and Control - Page 185

Excitotion Voltoge *Vx OV -vX Meosurement Sequence A/D Conv. SECTION 13. CRlO MEASUREMENTS Integrotion Integrotion A/D Conv. Time (milliseconds) FIGURE 13.5-2. Excitation and Measurement Sequence for 4 Wire Full Bridge TABLE 13.5-1. Comparison of Bridge Measurement Instructions lnstr. # Circuit Description lnstr. # Circuit Description 4 DC Half Bridge The delay parameter allows the user entered 7 3 Wire Compensates for lead Half Bridge wire resistance, settling time compensate for capacitance in long lead lengths. No assuming resistance is same in both wires. Two single-ended polarity reversal. One single-ended measure- measurements at each excitation polarity. ment. Measured Ratiometric output. voltage output. AC Half Bridge Bapid reversalof excitation polarity for ion depolarization. One single-ended measurement at each excitation polarity. Ratiometric output. Wire 4 One differential Bridge Full measurement at each excitation polarity. Ratiometric output. Differential Makes a differential Measurement measurementwithout with Excitation reversing excitation polarity. Used for fast measurements on load cells, PRTs etc. Resolution and common mode rejection worse than 6 if used with delay = 0. Measured voltage outPut. 6 Wire Compensates for lead FullBridge or 4 Half Wire Bridge wire resistance. Two differential measurements at each excitation polarity. Ratiometric output. 13-19