Pin assignment, display and diagnosis

EL3201-00x0

	Four-wire connection The EL3202-0010/0020/0030 high-precision terminals may be operated as intended only using the 4-wire connection technique!

EL3202-00x0 – pin assignment

Terminal point	No.	Comment
+R1	1	Input +R1, current-carrying
+RL1	2	Input +RL1, de-energized sense line
-R1	3	Input -R1, current-carrying
-RL1	4	Input -RL1, de-energized sense line
+R2	5	Input +R2, current-carrying
+RL2	6	Input +RL2, de-energized sense line
-R2	7	Input -R2, current-carrying
-RL2	8	Input -RL2, de-energized sense line

Notice

Increased measurement uncertainty with signal bundling of the AGND line

In this terminal, the AGND contacts (signal return line -R) are connected in the terminal.
If the connection lines are to be reduced on the system side, one line instead of n lines can be used for all n RTD sensors at this terminal.
However, since each channel individually permanently drives its measuring current (some 100 µA, see explanations chapter "RTD measurement in EL32xx"), all n RTD currents then flow via one line, there is an n-fold increase in voltage drop there, which is also recorded by the ratiometric voltage measurement in the terminal.
The result is the same as for long lines. If RTD sensors are to be connected in this way, a system-side check and, if necessary, compensation using WireCalibration CoE 0x80n0:1B (convert voltage drop to apparent line resistance for this purpose) or UserScale 0x80n0:11/12 is recommended.
Since the line resistances are temperature-dependent and the measuring current depends on the RTD resistance, however, such a static "compensation" cannot achieve the measurement uncertainty as in operation with two lines connected short.

	Connection of analog RTD signal lines To ensure that the analog signals can be measured with as little interference as possible, also observe the notes in the chapter "Connection of analog RTD signal lines".

EL3202-00x0 - LEDs

LED	Color	Meaning
RUN	green	This LED indicates the terminal's operating state:
		off	State of the EtherCAT state machine: INIT = initialization of the terminal or BOOTSTRAP = function for firmware updates of the terminal
		flashing	State of the EtherCAT state machine: PREOP = function for mailbox communication and different standard-settings set
		Single flash	State of the EtherCAT state machine: SAFEOP = verification of the sync manager channels and the distributed clocks. Outputs remain in safe state
		on	State of the EtherCAT state machine: OP = normal operating state; mailbox and process data communication is possible
ERROR1, ERROR2	red	Short circuit or wire breakage. The resistance is in the invalid range of the characteristic curve