The invention relates to an apparatus for monitoring a conveying installation, comprising: a conveying belt (2) made of elastomeric material with a load-bearing side (3) for the conveying material and with a running side (4), the conveying belt having, in particular, an embedded reinforcing element (7); at least one detectable segment (8) which is embedded in the load-bearing side (3) and/or running side, in the vicinity of the surface; a detection system (6), in particular in the form of an optoelectronic system, which contactlessly senses and evaluates the detectable segment (8), in particular in conjunction with a process computer; and other installation parts, namely a drive drum, reversing drum, supporting rollers, supporting frameworks, and possibly other components; the detectable segment (8) being based on a thermochromic substance which results in a change in color if the temperature changes within the critical temperature range of a conveying belt, the detection system (6) sensing and evaluating the change in color.