This family of peripherals expands the already formidable measurement and control capabilities of Campbell dataloggers.

Measurement peripherals are situated between the datalogger and its sensors, while control peripherals are situated between the datalogger and external device(s) under datalogger control.

Examples of measurement peripherals include vibrating wire interfaces, serial data interfaces, terminal input modules, and in most cases, multiplexers. Examples of control peripherals include relay drivers, some SDM peripherals, and occasionally, multiplexers. Some SDM devices can perform both measurement and control functions simultaneously.

As a group, these peripherals range from quite simple --- in the case of the precision resistor networks in our voltage dividers, to quite sophisticated --- in the case of SDM devices that have their own microprocessors and can perform measurement, control, and data processing functions independently of the connected datalogger.

In many cases, these devices increase the channel capacity of the dataloggers by allowing more sensors to be measured or more external devices to be controlled than is possible with the datalogger alone.

In some instances, the capabilities of the peripheral can provide additional capabilities to those available in the datalogger.