Siemens S7 1200 Digital Input Signal Board SB 1221 DI 4 6ES7221-3AD30-0XB0 Price in Bangladesh | Siemens S7 1200 signal Board Best Price

• Siemens Digital Input Signal Board

  Part Number: 6ES7221-3AD30-0XB0

  Parameter	Specification
  Product Family	SB 1221 Signal Board
  PLC Series	SIMATIC S7-1200
  Digital Inputs	4 DI
  Input Voltage	5 V DC
  Input Frequency	Up to 200 kHz (High-speed input)
  Input Type	Sourcing input
  Supply	From PLC backplane bus (5 V DC)
  Dimensions (W × H × D)	38 × 62 × 21 mm
  Power Loss	≈1 W
  Mounting	Installed inside S7-1200 CPU front slot
  Protection Class	IP20

  Product Description:
  6ES7221-3AD30-0XB0 is a SIMATIC S7-1200 SB1221 digital input signal board that provides 4 high-speed 5 V DC digital inputs (up to 200 kHz). It is installed directly inside the CPU signal board slot, allowing additional inputs without using a full expansion module.

  Key Features

  • 4 digital inputs (5 V DC)

  • High-speed input capability up to 200 kHz

  • Compact signal board expansion (no extra DIN-rail space required)

  • Ideal for high-speed sensors, encoders, and pulse signals

  • Configurable in TIA Portal

  Typical Applications

  • High-speed counters

  • Encoder signal reading

  • Pulse measurement

  • Position / speed monitoring systems

  Difference Between S7-1200 DI Types

  Type	Example Part Number	Installation
  Digital Input Module (SM)	6ES7221-1BH32-0XB0	Right side of CPU
  Signal Board (SB)	6ES7221-3AD30-0XB0	Inside CPU front slot

6. Analog Input / Output Combined Modules (SM 1234)

Module	Description	Part Number
SM 1234	4AI / 2AO	6ES7234-4HE32-0XB0
SM 1234	2AI / 2AO (Signal board type)	6ES7234-5HD30-0XB0