SIMATIC PLC S7 300 6ES7321-1BH02-0AA0 SM 321, DI 16×24V DC

SIMATIC S7-300 PLC 6ES7321-1BH02-0AA0 SM 321, DI 16×24V DC

I. Product Description:

The SIMATIC 6ES7321-1BH02-0AA0 is a digital input module from SIMATIC’ SIMATIC S7-300 series; its full model number is SM 321, DI 16×24V DC. It is a basic, cost-effective module designed to acquire 16 channels of 24V DC digital signals

16 digital input channels, 24 V DC; input characteristics comply with the IEC 61131 Type 1 standard

Rated voltage: 24 V DC

Powered by a 24 V DC load power supply; draws a maximum of 10 mA from the backplane bus; typical power consumption: 3.5 W

II. Product Specifications:

SIMATIC 6ES7321-1BH02-0AA0｜SIMATIC S7-300 SM 321 Digital Input Module

Permitted Input Voltage Range: 20.4 to 28.8 V DC;
Input Type: Sink/source;
Input Characteristic: IEC 61131-2 Type 1;
Signal "0" Input Voltage: -3 to 5 V DC;
Signal "1" Input Voltage: 15 to 30 V DC;
Input Current at Signal "1": Approximately 7 mA;
Input Delay: Approximately 1.2 to 4.8 ms;
Input Frequency: Up to 100 Hz;
High-Speed Inputs: Not intended for high-speed counting applications;
Channel Grouping: 16 inputs arranged in 2 groups of 8 channels;
Electrical Isolation: Inputs electrically isolated from the backplane bus;
Hardware Interrupts: Supported according to configured parameters;
Diagnostic Functions: Module diagnostics supported;
Status Indication: LED status indication for individual input channels;
Power Supply: 24 V DC;
Backplane Bus Current Consumption: Approximately 30 mA at 5 V DC;
Typical Power Loss: Approximately 3.5 W;
Front Connector: 20-pin front connector;
Engineering Software: STEP 7 / TIA Portal;
Configuration: Parameterizable through the STEP 7 engineering environment;
System Compatibility: SIMATIC S7-300 automation systems;
Mounting: Installation on the S7-300 mounting rail;
Protection Rating: IP20;
Operating Temperature: 0 to 60 °C;
Storage / Transport Temperature: -40 to 70 °C;
Maximum Cable Length: Up to 600 m for shielded cables and up to 1,000 m for unshielded cables, depending on signal conditions;
Dimensions (W × H × D): Approximately 40 × 125 × 120 mm;
Net Weight: Approximately 210 g;
Typical Applications: Digital sensor signal acquisition, switch monitoring, proximity sensor interfaces, machine automation, conveyor systems, packaging equipment, production lines, and industrial automation systems based on the SIMATIC S7-300 platform

III. Technical Parameters:

SIMATIC S7-300, digital input SM 321, isolated, 16 DI, 24 V DC, 1x 20-pole

IV. Industries Served:

The SIMATIC 6ES7321-1BH02-0AA0 serves as a basic digital input module for the S7-300 system.

Typical application scenarios explicitly mentioned for this module include: In automotive production lines and robotic workcells, it can be used to acquire signals from various sensors to enable precise position monitoring and safety interlocks.

The most common application areas. This module is widely used in equipment such as packaging machinery, machine tools, assembly lines, and material handling systems to acquire signals from pushbuttons, limit switches, and proximity switches, providing inputs for the automatic operation of the equipment.

The S7-300 PLC is widely used in the field of process control, and this module serves as one of its input components.

V. Why choose us?

We source directly from China’s Tier 1 channels, eliminating all middleman markups. This means you get competitive prices close to factory cost, and we pass those savings on to you as profit or budget flexibility for your projects.

Don’t let stockouts slow down your project schedule. For popular models like the S7-1500 and G120, which are frequently purchased, we always maintain high levels of in-stock inventory. The moment you place your order, the goods are already ready in our warehouse. Within 1–3 business days, you’ll receive the tracking number for your international express shipment. Whether your factory is in the Middle East, Southeast Asia, or across Europe and the Americas, our global logistics network helps you reclaim valuable time.

From precision manufacturing in Europe to oil and gas fields in the Middle East, and electronics assembly lines in Southeast Asia, our products and solutions have withstood the test of demanding operating conditions around the world. We deeply understand the unique characteristics of each market, and this global experience is the guarantee of your project’s successful implementation.

We don’t just sell products—we provide the technical support that keeps your equipment running smoothly. Whether you’re facing challenges with product selection, encountering commissioning errors, or dealing with unexpected failures, our technical team is always on standby to ensure your production line issues receive a professional response—not just a voicemail.

VI. FAQ:

1,How to buy the product?

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