HD EtherCAT Terminal, 8-channel thermocouple input with open-circuit recognition EL3318
Signal LEDs
1…8
Error LEDs
9...16
Power contact
+24 V
Power contact 0 V
+TC1 
+TC2 
+TC3 
+TC4 
+TC5 
+TC6 
+TC7 
+TC8 
-TC1
-TC2
-TC3
-TC4
-TC5
-TC6
-TC7
-TC8
Top view 
Contact assembly 
Observe for earthed
thermocoupler: differential
inputs max. ± 2 V to ground

EL3318 | HD EtherCAT Terminal, 8-channel thermocouple input with open-circuit recognition

The EL3318 analog input terminal allows eight thermocouples to be connected directly and is thus particularly suitable for space-saving use in control cabinets. The EtherCAT Terminal circuit can operate thermocouple sensors using the 2-wire technique. A microprocessor handles linearisation across the whole temperature range, which is freely selectable. The error LEDs indicate a broken wire. Compensation for the cold junction is made through an internal temperature measurement at the terminal. The EL3318 can also be used for mV measurement.

The HD EtherCAT Terminals (High Density) with increased packing density feature 16 connection points in the housing of a 12 mm terminal block.

Technical data EL3318
Number of inputs 8
Power supply via the E-bus
Thermocouple sensor types types J, K, L, B, E, N, R, S, T, U (default setting type K), mV measurement
Distributed clocks –
Input filter limit frequency typ. 1 kHz; dependent on sensor length, conversion time, sensor type
Connection method 2-wire
Wiring fail indication yes
Conversion time approx. 5 s up to 40 ms, depending on configuration and filter setting, default: approx. 500 ms
Temperature range in the range defined in each case for the sensor (default setting: type K; -200…+1,370 °C); voltage measurement: ±30 mV…±75 mV
Resolution 0.1 °C per digit
Measuring error < ±0.3 % (relative to full scale value)
Electrical isolation 500 V (E-bus/signal voltage)
Current consumption power contacts –
Current consumption E-bus typ. 210 mA
Bit width in the process image 8 x 32 bit TC input, 8 x 16 bit TC output
Configuration no address setting, configuration via the controller
Conductor types solid wire, stranded wire and ferrule
Conductor connection solid wire conductors: direct plug-in technique; stranded wire conductors and ferrules: spring actuation by screwdriver
Rated cross-section solid wire: 0.08…1.5 mm²; stranded wire: 0.25…1.5 mm²; ferrule: 0.14…0.75 mm²
Special features open-circuit recognition
Weight approx. 70 g
Operating/storage temperature 0…+55 °C/-25…+85 °C
Relative humidity 95 %, no condensation
Vibration/shock resistance conforms to EN 60068-2-6/EN 60068-2-27/29
EMC immunity/emission conforms to EN 61000-6-2/EN 61000-6-4
Protect. class/installation pos. IP 20/variable
Product announcement
 estimated market release 1st quarter 2012