Technology

General

Two channels of the EL3204-0162 analog input terminal enable direct connection of resistance sensors in 2-wire technology. A micro-controller within the terminal is used for converting and linearizing the resistance to a temperature value.

The temperatures are displayed as follows:

• Measuring range 10 to 1047 Ω: 1/64 ohm
• Measuring range 10 to 4095 Ω: 1/16 ohm
  (The use of the terminal in the range 0 to 10 ohm is not recommended)
• All other measuring ranges: 1/10 °C (1 digit = 0.1 °C)

Besides that, a wire break is reported to the controller and indicated by the ERROR LED. Pt100, NI100, Pt200, Pt500, NI120, NI1000 and Pt1000 elements are implemented over their full measuring ranges as resistance sensors. The terminal can be fully configured over the fieldbus. A self-defined scaling of the output can, for instance, be performed, or the temperature conversion can be switched off.

Characteristic curves for KT/KTY sensors are implemented and selectable via the CoE directory.

In the delivery state, the measured value is displayed in increments of 1/10 °C in two's complement format (integer). The complete measuring range is output for each resistance sensor. Other presentation types are selectable via index 0x8000:02 / 0x8010:02 (e.g. signed amount representation or high resolution with 1/100 °C).

Two further input channels of the EL3204-0162 can process analog signals in the range from 0 to 10 V or -10 to +10 V. The inputs are designed in 2-wire technology. See process data.