Abstract: A delayed-activation sensor system includes at least one microsensor. The microsensor may include at least one sensor module for sensing a condition in an environment and a dissolvable coating encapsulating at least a portion of the at least one sensor module such that the dissolvable coating prevents the at least one sensor module from sensing the condition in the environment. The dissolvable coating may be dissolvable in a fluid in the environment such that the sensor module is activated after being located in the environment for a period of time. The microsensor may also include at least one energy harvester module to generate electrical power for the microsensor from the environment.