The analog input module EP-3804 can detect up to 4 analog thermocouple sensors or voltages between ± 15 mV and ± 2 V. The resolution is 16 bit per channel. Sensor type and temperature range are set using parameterisation. Mixed operation using different sensors is possible. For each channel, an internal or external cold-junction compensation (CJC) can be parameterized. A status LED is assigned to each channel. The inputs are protected against voltage surges and overcurrent. Voltages that exceed ±30 V may cause the destruction of the module. The module provides individual channel diagnosis with channel related error messages.