Siemens

Siemens SIMATIC S5 WF 721 Positioning Module (6FM1721-3AA20)

SKU 6FM1721-3AA20

In stock
  • 12-month warranty
  • Free returns within 30 days

  • Manufacturer: Siemens

  • Product No.: 6FM1721-3AA20

  • Country of origin:Germany

  • Product Type: Positioning Modules

  • Barcode: 85389091

  • Payment: T/T, Western Union

  • Weight: 400g

  • Dimensions: 25.40cm x 2.50cm x 20.30cm

  • Shipping port: Xiamen

  • Warranty: 12 months

Description

The 6FM1721-3AA20 is a single-axis Positioning Module (WF 721) from the SIMATIC S5-135/155 family. Engineered by Siemens, this module provides high-precision motion control by processing feedback from position encoders. It is highly versatile, supporting both serial and incremental encoder interfaces, which allows it to adapt to various legacy automation setups. Despite being in a phase-out product lifecycle stage, it remains a critical component for the maintenance and operational continuity of older SIMATIC S5 control architectures in heavy industrial sectors.

Features

  • Single-Axis Control: Optimized for precise motion management of one machine axis.
  • Encoder Versatility: Supports integration with serial and incremental position encoders for flexible feedback loops.
  • Seamless Integration: Designed specifically for the S5-135/155 PLC racks.
  • Industrial Durability: Built to withstand the harsh conditions typical of legacy manufacturing environments.

Technical Specifications

Attribute Specification
Manufacturer Siemens
Range SIMATIC S5
Subrange S5-135/155
Model 6FM1721-3AA20
Product Type Positioning Module (WF 721)
Controlled Axes 1
Weight 0.40kg
Dimensions 25.40 x 2.50 x 20.30 cm
Commodity Code 85389091
PLM Product Phase Phase-Out

Installation Guidelines

  • Rack Insertion: Power down the S5-135/155 PLC rack before inserting or removing the WF 721 module to prevent electrical damage to the backplane.
  • Encoder Wiring: Ensure that encoder cables are shielded and kept separate from power-carrying conductors to prevent signal interference with the pulse-counting circuitry.
  • Grounding: Verify that the rack itself is properly grounded to ensure the stability of the low-voltage signals processed by the positioning module.
  • Configuration: Utilize the appropriate S5 programming tools to define the machine parameters and encoder scaling factors required for precise positioning.
  • Maintenance: Periodically inspect the edge connectors for signs of oxidation, which is common in older systems and can lead to intermittent positioning errors.

FAQ

How many axes can the 6FM1721-3AA20 module control?
This module is designed for the precise control of one single axis.

What type of encoders does this module support?
It supports both serial and incremental position encoders.

Which PLC series is this module compatible with?
It is designed for use with the Siemens SIMATIC S5-135 and S5-155 series.

Is this product still in active production?
No, the 6FM1721-3AA20 is currently in the phase-out stage of its lifecycle.

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  • Standard Delivery: 4–6 business days via DHL, FedEx, and UPS.
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Returns & Warranty

  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our technical warranty.
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Global Express Shipping

  • Standard Delivery: 4-6 Business Days via DHL, FedEx, and UPS.
  • Express Dispatch: Same-day dispatch for in-stock orders placed before 2:00 PM (GMT+8).
  • Worldwide Coverage: Serving over 150 countries, including rapid delivery to Saudi Arabia and UAE.

Returns & Warranty

  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our professional technical warranty.

Orders are processed and delivered Monday-Friday (excluding public holidays).


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TECHNICAL SPECIFICATIONS

Color pattern
Dots
Country of origin
Germany
Power source
DC Power

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