ST HE421N3-H1TF Pizzato ST H series safety sensor

ST HE421N3-H1TF Pizzato ST H series safety sensor

Pizzato ST HE421N3-H1TF is a 24 V DC ST H series RFID electronic safety interlock sensor with high-level actuator coding, dual safety outputs, signalling output, magnetic holding and an integrated 3 m cable for industrial machine guarding.

SKU: STHE421N3-H1TFAlt SKU: STHE421N3H1TFMPN: ST HE421N3-H1TF
Price
List Price £151.12 ex VAT
Your Price (ex VAT)
£151.12
Manufacturer Lead Time Standard Manufacturer Lead Time 5-6 Weeks, Call For Express Delivery Options
Get the best trade prices Trade exclusive

Create a trade account to unlock exclusive pricing, special offers and more.

SUBTOTAL (EX VAT) £151.12
Trade pricing is personalised to your account

Manufacturer Lead Time

£151.12

Why Choose the Pizzato ST HE421N3-H1TF ST H Series Safety Sensor?

The Pizzato ST HE421N3-H1TF is a robust RFID electronic safety interlock sensor with magnetic holding designed for reliable non-contact monitoring of guards, doors and access points on industrial machinery. As part of the advanced Pizzato ST H RFID Safety Sensor Series, it combines high-level RFID actuator coding with redundant electronic safety technology for dependable integration into modern machine safety systems.

Operating from a 24 V DC supply, the ST HE421N3-H1TF provides two safety outputs OS1–OS2 and one signalling output O3. Its electronic architecture is designed for connection to compatible safety modules and safety PLCs, providing reliable guard position monitoring while avoiding the mechanical wear associated with conventional contact-based safety switches.

The ST HE421N3-H1TF uses a high-level coded RFID actuator and incorporates the permanent magnet characteristic of the ST H series, helping keep guards closed against vibration, recoil and air turbulence. The N3 configuration provides an integrated 3 m cable, while the robust technopolymer housing, 78 mm mounting hole spacing and high ingress protection make the sensor suitable for demanding industrial installations.

Key Advantages

  • Reliable RFID non-contact safety interlocking for industrial machine guards.
  • High-level coded RFID actuator provides enhanced protection against inappropriate substitute actuation.
  • Integrated permanent magnet helps keep guards closed against vibration, recoil and air turbulence.
  • Non-contact sensing minimises mechanical wear and maintenance requirements.
  • Redundant electronic design supports high-performance machine safety applications.
  • Integrated 3 m cable simplifies installation and machine wiring.
  • Symmetrical housing allows convenient installation on left- or right-hand guards.
  • 78 mm mounting hole spacing facilitates upgrades from traditional SR B series magnetic sensors.
  • Robust construction supports operation in demanding industrial environments.

Key Features

  • Pizzato ST H RFID Safety Sensor Series.
  • 24 V DC supply voltage.
  • 2 safety outputs OS1–OS2.
  • 1 signalling output O3.
  • RFID coded non-contact actuator detection.
  • High actuator coding level.
  • Permanent magnet incorporated into the ST H housing.
  • Integrated 3 m cable.
  • Symmetrical technopolymer housing.
  • 78 mm mounting hole spacing.
  • Designed for high-performance industrial machine safety systems.
  • Suitable for connection to compatible safety modules and safety PLCs.
  • ST H series protection suitable for demanding industrial environments.

Reliable Safety Monitoring for Industrial Automation

RFID safety sensors such as the Pizzato ST HE421N3-H1TF monitor the position of machine guards by electronically recognising a coded actuator without requiring mechanical contact between the sensor and actuator. This non-contact operating principle reduces mechanical wear while providing dependable guard monitoring across the repeated opening and closing cycles found in automated machinery.

The ST H series combines RFID safety monitoring with an integrated permanent magnet that helps maintain guard closure where vibration, recoil or air turbulence could otherwise cause unwanted movement. High-level actuator coding and redundant electronics make the series particularly suitable for machine builders requiring reliable safety performance and resistance to deliberate or accidental bypassing.

Typical Applications

  • Industrial machine guard monitoring.
  • Safety doors and movable access panels.
  • Robotic cells and automated manufacturing systems.
  • Packaging and processing machinery.
  • Conveyor and material handling equipment.
  • Guards exposed to vibration, recoil or air turbulence.
  • OEM machine building and industrial safety systems.

Technical Specifications

Tick the specs you need, then view products that match.

Cable Length (m) 3 m
Product Series Pizzato ST H (RFID)
Sensing Principle RFID (coded)
Coding Level High (unique)
Contacts 2 safety outputs (OSSD) + 1 signalling
Supplied As Sensor + actuator kit
Connection Integrated cable
Manufacturer Pizzato Elettrica
Series ST H RFID Safety Sensor Series
Model ST HE421N3-H1TF
Product type RFID electronic safety interlock sensor with magnetic holding
Supply voltage 24 V DC
Safety outputs 2 (OS1–OS2)
Signalling output 1 (O3)
Detection technology RFID coded non-contact sensing
Actuator coding level High
Connection type Integrated fixed cable
Cable length 3 m
Housing material Technopolymer
Housing design Symmetrical ST H housing with permanent magnet
Mounting hole spacing 78 mm
Safety integrity level SIL 3 according to IEC 61508
HS Code 85369095

Frequently Asked Questions

What is the Pizzato ST HE421N3-H1TF used for?

The ST HE421N3-H1TF is designed for non-contact monitoring of machine guards, safety doors and access panels in industrial machinery and automation systems.

What supply voltage does the ST HE421N3-H1TF require?

The sensor operates from a 24 V DC supply for integration with industrial machine safety systems.

What safety outputs does the ST HE421N3-H1TF provide?

The sensor provides two electronic safety outputs OS1–OS2 together with a signalling output O3 for guard status indication and machine control integration.

What connection does the Pizzato ST HE421N3-H1TF use?

The N3 version is supplied with an integrated 3 m cable, providing a fixed electrical connection for installation on industrial machinery.

What actuator coding does the ST HE421N3-H1TF use?

The H1 configuration uses a high-level coded RFID actuator, providing enhanced protection against activation by an incorrect or substitute actuator.

Trusted by Machine Builders Worldwide

Pizzato ST H series RFID safety sensors are designed for machine builders and automation engineers requiring reliable non-contact guard monitoring, high-level actuator coding, magnetic holding and robust integration into modern industrial safety systems.

● Service Agreements

Credit Accounts

Our service agreements are built to support long term procurement relationships. By working closely with engineering teams and procurement departments, we help streamline purchasing processes while ensuring consistent access to critical components and sourcing support when it matters most.

 Priority sourcing and supply support

 Flexible payment terms for qualifying organisations

 Support for engineering, maintenance, and operations

500 +

Stock lines ready to ship

1,000 +

Same day dispatches

3500 +

Customers supported

28 

Trusted Manfacturers

● frequently asked questions

Common questions about our products and support

 

At Led Controls Ltd we help engineers source the right automation and control gear with confidence. below are quick answers to what we are asked most often.

What product ranges do you supply

We supply all leading manfacturers in our industry. we offer next day delivery on most poplour products. 

Can you help specify the correct part?

Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.

Do you have stock for urgent orders?

Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.

What are your delivery times and costs?

Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.

What about warranties, returns and faulty items?

Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.

● latest blog

Discover  our latest insights and
expert advice

From a Simple Idea to Small Business of the Year: The LED Controls Story So Far…

From a Simple Idea to Small Business of the Year: The LED Controls Story So Far…

LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.

LED Controls: Danfoss Drives Authorised Partner

LED Controls: Danfoss Drives Authorised Partner

2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...

LED Controls: Your Complete Control Panel Solution

LED Controls: Your Complete Control Panel Solution

2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...