Transformer bridges for use with resistance strain gauges and similar transducers
L N Clarke · Journal of Scientific Instruments · 1960
A method of balancing a.c. bridges having transformer ratio arms is described which is particularly suitable for use with resistance transducers such as electrical-resistance strain gauges. The long-time stability and accuracy of reading can be readily made better than required for most static testing by the use of an auxiliary transformer. The bridge can be combined with a commercial potentiometric recorder to form a multi-channel self-balancing a.c. bridge which can provide different ranges on successive channels. The balancing system lends itself to the control of testing machines, especially for the production of a given time-pattern of load or strain. The use of other types of transducers is considered.