Siemens 6ES7331-7KB02-0AB0 SIMATIC S7-300 Analog Input 2 AI 14-bit

The Siemens 6ES7331-7KB02-0AB0 is a SIMATIC S7-300 analog input module (SM 331) with 2 isolated analog inputs and a resolution of up to 14 bits. It accepts voltage, current, thermocouple, resistance thermometer, and resistance signals, and supports removal and insertion with the backplane bus active. Supplied as a spare part for existing S7-300 installations.

Technical specifications:

• MLFB: 6ES7331-7KB02-0AB0
• Manufacturer: Siemens
• Product line: SIMATIC S7-300
• Analog inputs: 2 (1 for resistance measurement)
• Resolution: 9/12/12/14 bit unipolar; 9/12/12/14 bit + sign bipolar; 15 bit with overrange
• Input types: voltage, current, thermocouple (E, J, K, N), RTD (Pt100, Ni100), resistance
• Voltage ranges: -10 V to +10 V, -5 V to +5 V, -2.5 V to +2.5 V, -1 V to +1 V, -500 mV to +500 mV, -250 mV to +250 mV, -80 mV to +80 mV, 1 V to 5 V
• Current ranges: 0-20 mA, 4-20 mA, -20 to +20 mA, -10 to +10 mA, -3.2 to +3.2 mA
• Resistance ranges: 0-150 , 0-300 , 0-600
• Integration time: 2.5 / 16.67 / 20 / 100 ms (parameterizable)
• Supply voltage: 24 V DC; power loss 1 W typical
• Isolation: channels isolated from backplane bus and electronics supply, tested at 500 V DC
• Cable length: max. 200 m shielded (50 m for 80 mV ranges and thermocouples)
• Front connector: 20-pin
• Dimensions (W x H x D): 40 x 125 x 120 mm
• Weight: approx. 250 g
• Approvals: FM (hazardous locations), CCC-Ex, NK (maritime), CCS (maritime)

Features and benefits:

• Isolated inputs protect the backplane bus from signal-side faults, with isolation tested at 500 V DC
• Single module covers voltage, current, thermocouple, RTD, and resistance – eliminating the need for separate input modules
• Parameterizable diagnostic and limit value alarms with group error LED for rapid fault identification
• Internal and external thermocouple cold-junction compensation with characteristic linearization for types E, J, K, N
• Hot-swap capable – can be removed and inserted with the S7-300 backplane bus energized

Applications:

• Temperature monitoring using Pt100 or Ni100 RTDs in S7-300 process control systems
• Acquisition of 4-20 mA signals from 2-wire and 4-wire process transmitters
• Thermocouple-based temperature measurement in manufacturing and process automation
• Spare part replacement in existing SIMATIC S7-300 analog input installations

Approved for use in hazardous locations (FM, CCC-Ex) and maritime applications (NK, CCS). Part of the Siemens SIMATIC range.

Also known as: Siemens 6ES7331-7KB02-0AB0, SIMATIC S7-300 SM 331 analog input module, S7-300 2AI signal module.