Increasingly higher demands are being placed on safety and system availability – across all sectors. Processes are becoming more and more complex, not only in mechanical engineering and the chemical industry, but also in plant and automation technology. Demands on power engineering are also increasing constantly.
Error-free and therefore cost-effective operation can only be achieved through continuous monitoring of important network and system parameters. Electronic monitoring relays in the EMD series are available for a wide range of monitoring tasks to avoid the consequences of errors or to keep them within limits.
The operating states are indicated using colored LEDs, errors that may occur can be sent to a control system via a floating contact or can shut down a part of the system. Some device versions are equipped with startup and response delays in order to briefly tolerate measured values outside the set monitoring range.
Ambient temperature (operation)
-25 °C ... 55 °C
-25 °C ... 40 °C (corresponds to UL 508)
Ambient temperature (storage/transport)
-25 °C ... 70 °C
Nominal input voltage UN
400 V (3 N ~ 400/230 V)
Phase sequence, phase failure, asymmetry
Min setting range of the voltage threshold value
342 V AC
Max. setting range of the voltage threshold value
457 V AC
Setting range for response delay
≤ 350 ms (fixed setting)
Setting range for starting delay
≤ 500 ms (fixed setting)
Fixed, approx. 30 %
< 100 ms
2 floating PDT contacts
Maximum switching voltage
250 V AC (in acc. with IEC 60664-1)
Interrupting rating (ohmic load) max.
750 VA (3 A/250 V AC, module aligned, ≤ 5 mm spacing)
1250 VA (5 A/250 V AC, module not aligned, ≥ 5 mm spacing)
5 A (fast-blow)
From the measured voltage
Mechanical service life
Approx. 2 x 107 cycles
100% operating factor
on standard DIN rail NS 35 in accordance with EN 60715