Current implementations of digital controllers assume that sensing, control and actuationare performed in a periodic fashion. In classic control schemes, where sensors and controllers aredirectly connected, periodicity does not provide particular drawbacks, but, in the case of wireless sensornetworks, such a choice may be questionable. One of the driving constraints in the design of wirelesssensor networks is represented by its energy efficiency, and it has been shown that the main cause ofenergy consumption is due to the radio activities of the sensor nodes. By using periodic implementations,the sensor nodes are enforced to keep on transmitting measurements to the controller even if it is notreally needed, thus wasting energy. To cope with these problems, self-triggered control was recentlyintroduced. This technique aims at reducing the conservativeness of periodic implementations providingan adaption of the inter-sampling intervals based on the current output of the system. Existing workon self-triggered control considers linear systems controlled by state feedback controllers under theassumption of small time-delays. In this paper the problem of designing a self-triggered control schemethat applies to first-order processes with large dead-times controlled by PI controllers is addressed.Moreover, the proposed self-triggered scheme is robust with respect to set-point changes and externaldisturbances, which are typical in process industry. The results are validated by simulations.