A low-cost modular data-acquisition system for monitoring biometeorological variables

•A low-cost DAQ system was designed and implemented for measuring biometeorological variables.•Due to its general-purpose design the system can operate on either the RS-232 or RS-485 protocols.•Malfunctioning parts can be replaced without affecting the operation of the rest of the system.•Two ECTs were built and installed at remote sites during long-term deployments.•Field operation showed a robust, high-frequency, and high-reliability DAQ system performance.