Not recommended for new design. Use DW4 instaed. Wire Breakage Detector with 24V malfunction message output. Load range 5mA...3A. Shape 17,5mm. Wire Breakage Detector  - Short-Circuit Monitoring For load currents 5mA - 3A Short switching times 60µs/100µs Monitoring also in idle state Short-circuit proof, 30s Status display in front panel Malfunction message output plus switching 24VDC/50mA Mountable on 35 mm cap rail TS35 Clear terminal labeling Narrow design Shape 17,5mm, superlow PB - Power-Bus - compatible High reliability, 5 years warranty The Wire Breakage Detectors of the series DW1 have been developed for the monitoring of  24V consumers and their connection lines for wire breakage and short-cicuit. The proper condition of the line is signaled via an plus switching optocoupler output. The wire breakage detectors are used in alarm- and extinguishing systems. Datasheet 

Not recommended for new design. Use DW4 instaed. Wire Breakage Detector. NC as malfunction message output . Load range 5mA...3A. Shape 17,5mm. Wire Breakage Detector - Short-Circuit Monitoring  For load currents 5mA - 3A Short switching times 60µs/100µs Monitoring also in idle state Short-circuit proof, 30s Status display in front panel Malfunction message output, NO, analog switch, 30VDC/100mA Mountable on 35mm cap rail TS35 Clear terminal labeling Narrow design Shape 17,5mm, superlow PB - Power-Bus - compatible High reliability, 5 years warranty The Wire Breakage Detectors of the series DW2 have been developed for monitoring of  24V consumers and their connection lines for wire breakage and short-circuit. The proper condition of the line is signaled via an plus switching optocoupler output. The wire breakage detectors are used in alarm- and extinguishing systems. Datasheet 

Wire Breakage/Short-Circuit Monitoring for switch contacts, shape 17,5mm. Wire Breakage Monitoring - Line Monitoring for Switch ContactsN/O / N/C monitoringMonitoring also in idle stateStatus display in front panelMalfunction message output, N/O, analog switch, 30VDC/100mASignal output optodecoupled Mountable on 35mm cap rail TS35Clear terminal labelingNarrow designShape 17,5mm, superlowPB - Power-Bus - compatibleHigh reliability, 5 years warrantyThe devices of the Wire Breakage Monitoring series DW3 have been developed for line monitoring of mechanical switch contacts like for example N/O or N/C contacts for wire breakage and short-circuit. The proper condition of the line connection is signaled via a potential free electronic contact, which in case of failure opens (closed current condition). The switching condition of the monitored contact is also signaled via a potential free electronic contact and additionally via a relay contact (changeover). This switching condition can be inverted via Dip-switch S1-1. The switch S1-2 is functionless and is intended for later extensions. At N/O's the monitoring of a complete reporting chain with any number of contacts is possible, at N/C's only single contacts can be monitored. The devices are easily mountable on cap rail and need an auxiliary power of 24VDC. Datasheet

Wire Breakage Monitoring – Short Circuit Monitoring, Wire Breakage Monitoring for Flashlights and Sirens.For load current 5mA - 3AMonitoring also in idle conditionOptimized for flashlights and sirensShort circuit proof, 30sStatus display in front panelFault signal output, N/C, analog switchSupply 24VDCMountable on 35mm cap rail TS35Clear terminal labelingNarrow designShape 17,5mm, super lowPB - Power-Bus compatibleHigh reliability, 5 years warrantyThe devices of the wire breakage detector series DW4 have been developed for monitoring of both driven as well as non-driven consumer wires. They correspond in their functioning to the series DW2, but they were optimized especially for flashlights and sirens. (They also can be used for other consumers as for example magnetic valves or resistive loads). Because they have a pulsating current consumption during operation, a wire breakage during driven condition will be signaled after a delay time of ca. 6 seconds, during non-driven operation there is no delay of the report.Datasheet

Fan – Speed monitoring, Power supply 24VMonitoring a fan speedfor ground-switching outputs1 to 4 fansStatus display in the front of the deviceCollective alarm outputSupply 24VDCfor mounting rail mounting TS35clear terminal markingsmall dimensionsThe fan monitoring devices LU1 are used for speed monitoring of fans with ground-switching tachometer signal output. Up to 4 fans can be monitored in parallel. The minimum speed can be set separately for each fan or jointly for all 4 fans via a 20-turn spindle potentiometer, depending on the device version. If the set minimum speed of a fan is not reached, this is indicated via a common fault signal output (relay de-energised / quiescent current principle) and a red LED in the front of the housing indicates the fault for the corresponding channel (depending on the device variant). A green LED indicates that the device is ready for operation. The devices require an auxiliary power of 24Vdc and can be snapped onto TS35 mounting rail.Datasheet

Fan speed monitorung with NPN input. smal housing 6,2mm. Without cover plate. Monitoring a fan speedfor ground-switching outputs1 FanStatus display in the front of the deviceCollective alarm outputSupply 24VDCfor mounting rail mounting TS35clear terminal markingsmall dimensionsDesign 6.3mm, terminal housinghigh reliability, 5 years warrantyThe fan monitoring devices LU2 are used for speed monitoring of fans with ground switching signal output. The minimum speed can be set via a potentiometer. If the set minimum speed of the fan is not reached, this is signalized via a common fault signal output transistor and a green LED in the front of the housing indicates the fault. The function of this signal output can be switched via a dip switch. S1-1 set to off means that the output switches off (0V) when the fan speed falls below the set value, whereas S1-1 set to ON the output is set to on (24V). The devices require an auxiliary power of 24Vdc and can be snapped onto TS35 mounting rail.Datasheet