• Continuous measurement and display of voltage
• Customer-friendly menu for setting the parameters
• Storing the parameters in the internal memory
• Adjustable under-voltage, hysteresis and switching delay
• Display for circuit below the set threshold
• Display of relay operation after the expiry of the delay time
• Simultaneous display of under voltage
• Potential-free change-over contacts 5A / 250V
• Narrow 26mm DIN-Rail Housing

• Large setting range 10 - 14V / 20 - 28V
• Precision < 1%
• LED display after voltage falls below threshold
• Drop-off time delay adjustable from 0.5 - 100 sec
• Two-way output contact

Trigger unit for battery undervoltage protection, especially for monitoring the starter battery for diesel-driven generators. In the output, the unit has a two-way contact switched as a normally open contact.

• Two-stage frequency monitor with LCD digital display
• Threshold adjustable from 40 - 70Hz
• 0.05% precision of the frequency display
• Updating of frequency measurement every 20ms
• Switching delay adjustable from 10ms - 60 Sec
• Modern system, menu-driven and saved in EEPROM
• Output two-way contacts

This unit is used for monitoring the frequency of an AC mains network, especially in free-running off-mains networks, combined heat and power stations and emergency power supplies. As the DFW100 records the connected frequency with high precision ( better than 0.05% ), the unit is also suitable for monitoring the mains frequency in interconnected networks. The frequency monitor has an easy-to-use menu interface with an LCD display. The settings can be reprogrammed by the user during operation of the unit.

• Two-stage frequency monitor for 50Hz network application
• Underfrequency and overfrequency adjustable individually
• Continuous setting range +/- 20%
• LED displays for exceeding of values set
• Separate output via 2 output relays
• Two-way output contacts

The unit is used for detecting the mains frequency or generator frequency, especially for frequency monitoring in free-running networks. The underfrequency relay is active at the rated frequency and the overfrequency relay is not switched through. The unit is supplied with an auxiliary voltage via the measuring voltage.

• 2-way frequency monitoring with seperate output relay
• Digital displaying of actual frequency in Hz
• High accuracy of monitoring better 0,05%
• Event displaying of switch point overdrive
• Changing and displaying of setting values on LCD with bright contrast
• setting possibility of 2 frequency switch points with hysteresis and switching delay
• setting values to change by easy menu handling, saving into eeprom
• 5 – 264VAC input range of measuring voltage

The speed controller RFR500 is used to monitor the starting frequency and rated frequency of generators or gensets. With channel 1 the frequency will be monitored during starting of genset under low mains voltage until the start frequency ( 10-30Hz ) reached ( end of start ) by swiching of relay 1 (starting mashine will be stoped). The 2. channel monitors the rated frequency (50Hz) and is i.e. set to 49,9Hz. With this there is also a monitoring for underfrequency during normal running. The change of switchpoints for frequency, hysteresis or of switching delay (10ms – 60sec.) may be changes during normal running (easy programming) and will be used after storing into eeprom. The auxiliary voltage 24VDC will be get from battery, other supply voltages are available on request.

• 3-phase load current recording
• Differential current evaluation in percent
• Trigger range 5 - 15% of the instantaneous average value
• Switching delay ~0,2 - 5 sec
• LED displays for exceeding and triggering
• Two-way output contacts
• Auxiliary voltage 231VAC or 24VDC

The unit is usually used for motor / generator protection in 3- or 4-wire AC mains networks. It records the current of each individual wire and compares them with the average value for all three phases. In the case of undershooting or overshooting of a phase in comparison with the deviation in % set ( 5-50% ), the internal time circuit is triggered on completion of which the relay switches through.

• Two-stage 3/4-wire phase voltage monitoring
• Short release time < 50ms after undershoot or overshoot
• < 1% precision of switching points
• Auxiliary voltage supply from measuring voltage
• Separate adjustment for undervoltage and overvoltage
• Two-way output contacts

Trigger unit for undervoltage and overvoltage protection in 3- or 4-conductor AC mains networks.Each phase is recorded individually and causes the two-way output contacts to be triggered in the case of undershooting or overshooting of the setpoint value. The switching state is displayed via LED`s. Special evaluation circuitry allows rapids recording of values while suppressing interference to a high degree. The undervoltage relay is switched as a normally open contact and the overvoltage relay is switched as a normally closed contact.

• Input signal 0 - 20mA
• Threshold continuously adjustable from 0 - 100%
• LED display for exceeding of threshold
• Switching delay adjustable from 0.1 - 3 sec
• Two-way output contact
• Auxiliary voltage supply 231V

Trigger unit for 20mA applications in 55mm standard housing. Available for pick-up current delay and drop-off time delay of the output relay contacts. The scaling of the adjuster for the threshold ( 0-20mA) can be read off in %. Under the designation of GWG..., the unit is offered as a threshold indicator with a continuously adjustable 0-20 mA signal as an output.