This unit is used for checking for the slowing down of rotating units due to the slipping of belts of clutches, fracture of transport belts or chains or as a motor protection in the case of mechanical overload. This control is carried out by the CRTP controller which is made up of an electronic circuit which is enclosed in a plastic container which has an undecal plug and a sensor which can be inductive, capacitive or photoelectric. - Power supply 24-110/220 Vac 50/60 Hz- Relay output 1 pole changeover 5A to 220 Vac- Led incorporated- The time range goes from 0.03 sec. to 512 sec- Initial delay is adjustable in order to permit rotating unit to start- Function A with alarm and manual reset- Function B with alarm and automatic reset- Adapted for NAMUR and amplified NPN or PNP sensor- All the functions are programmed through a selector switch- In case of loss of power, the relay changes state thus giving the alarm condition