2-channel digital input terminal with timestamping EL1252
Signal LED2
Signal LED1 
Power contact
+24 V
Power contact 0 V
Power contact PE
Input 1
Input 2
+24 V
0 V
PE
Top view 
Contact assembly 
XFC – eXtreme Fast Control
extended temperature range
extended shock and vibration range

EL1252 | 2-channel digital input terminal with timestamping

The EL1252 digital input terminal acquires the fast binary control signals from the process level and transmits them, in an electrically isolated form, to the controller. The signals are furnished with a timestamp that identifies the time of the last edge change with a resolution of 1 ns. This technology enables signals to be traced exactly over time and synchronised with the distributed clocks across the system. With this technology, machine-wide parallel hardware wiring of digital inputs or encoder signals for synchronisation purposes is often no longer required. In conjunction with the EL2252 EtherCAT Terminal (digital output terminal with timestamp), the EL1252 enables responses with equidistant time intervals, largely independent of the bus cycle time.

Technical data EL1252 | ES1252
Connection technology 4-wire
Specification similar to EN 61131-2, type 3, “0”: -3…5 V DC, “1”: 11…30 V DC, typ. 3 mA input current
Number of inputs 2
Nominal voltage 24 V DC (-15 %/+20 %)
“0“ signal voltage -3…+5 V (similar to EN 61131-2, type 3)
“1“ signal voltage 11…30 V (similar to EN 61131-2, type 3)
Input current typ. 3 mA (similar to EN 61131-2, type 3)
Input filter typ. < 1 µs
Resolution timestamp 1 ns (channel 0/1)
Precision of timestamp in the terminal 10 ns (+ input delay)
Distributed clock precision << 1 µs
Input delay TON/TOFF < 1 µs
Distributed clocks yes
Time resolution signal 1 ns
Current consumption power contacts typ. 6 mA + load
Current consumption E-bus typ. 110 mA
Electrical isolation 500 V (E-bus/field potential)
Bit width in the process image 2 inputs + 36 byte timestamp
Configuration no address or configuration setting
Special features timestamping, latch last edge
Weight approx. 55 g
Operating/storage temperature -25…+60 °C/-40…+85 °C
Relative humidity 95 %, no condensation
Vibration/shock resistance conforms to EN 60068-2-6/EN 60068-2-27
EMC immunity/emission conforms to EN 61000-6-2/EN 61000-6-4
Protect. class/installation pos. IP 20/variable
Pluggable wiring for all ESxxxx terminals
Approvals CE, UL, Ex
Related products
EL1252-0050 2-channel digital input terminal 5 V DC, filter 1 µs, with time stamp
Further information  
XFC eXtreme Fast Control Technology