Why Choose the ABB 1SFN030300R1000 VM19 Mechanical Interlock Unit?
The ABB 1SFN030300R1000, also known as the VM19, is a robust mechanical interlock unit designed for use with ABB AF series contactors. It provides a safe mechanical interlocking function between two contactors of the same frame size, preventing both devices from closing simultaneously and ensuring safe operation in reversing and changeover motor control circuits.
Developed for industrial automation, OEM machinery and motor control applications, the VM19 installs directly between two compatible contactors. Its compact design eliminates the need for complex external interlocking mechanisms while increasing operational safety and reliability in demanding industrial environments.
Compatible with ABB AF116 to AF370 contactors of the same frame size, the ABB 1SFN030300R1000 is the ideal accessory for reversing starters, transfer switching applications and interlocked contactor assemblies requiring dependable mechanical locking.
Key Advantages
Provides reliable mechanical interlocking between two contactors.
Prevents simultaneous closing of both contactors.
Designed for ABB AF116 to AF370 contactors.
Suitable for reversing and changeover motor starter assemblies.
Improves operational safety and system reliability.
Key Features
ABB VM19 mechanical interlock unit.
Part number 1SFN030300R1000.
Mechanical interlock accessory.
For two contactors of equal frame size.
Compatible with AF116...AF370 contactors.
No auxiliary contacts required for mechanical locking.
Compact side-by-side installation.
Robust industrial construction.
Maintenance-free operation.
Suitable for industrial motor control systems.
Safe Mechanical Interlocking for Industrial Contactors
Mechanical interlock units are essential for reversing starters and changeover applications where two contactors must never close simultaneously. The ABB VM19 provides a simple yet highly effective mechanical locking mechanism that physically prevents simultaneous operation, helping protect motors, power circuits and connected equipment.
Its durable construction and direct mounting arrangement allow panel builders and OEM manufacturers to create compact, reliable motor control systems while maintaining high safety standards throughout the installation.
Typical Applications
Reversing motor starters.
Forward and reverse motor control.
Industrial control panels.
Transfer and changeover systems.
Machine building.
OEM automation equipment.
Industrial switchgear assemblies.
Technical Specifications
Series
VM Mechanical Interlock Units
Part number
1SFN030300R1000
Product type
Mechanical interlock unit
Application
Reversing and changeover contactor interlocking
Compatible contactors
AF116..AF370, AF116B..AF370B, AX260..AX370
Mounting type
Side-by-side contactor mounting
Connection compatibility
Screw terminal contactors
Construction
Industrial insulated thermoplastic and metal mechanism
Protection function
Prevents simultaneous contactor operation
Dimensions (W × H × D)
approx. 70 × 58.7 × 31.9 mm
Weight
approx. 0.05 kg
Standards
EN 60947-4-1, UL 60947-4-1
Frequently Asked Questions
What is the ABB 1SFN030300R1000 used for?
It is a mechanical interlock unit that prevents two compatible ABB contactors from closing at the same time.
Which contactors is the VM19 compatible with?
The VM19 is designed for ABB AF116 to AF370 contactors of the same frame size.
Why is a mechanical interlock required?
Mechanical interlocking prevents simultaneous operation of reversing or changeover contactors, protecting motors and electrical systems from faults.
Does the VM19 require electrical wiring?
No. The VM19 operates purely as a mechanical interlock and does not require electrical connections.
Where is the VM19 typically installed?
It is installed directly between two side-by-side compatible ABB contactors in reversing or changeover motor control assemblies.
Trusted by Industrial Automation Professionals
ABB VM mechanical interlock units are trusted by panel builders, OEM manufacturers and automation engineers for delivering safe, reliable interlocking in reversing motor starters and industrial control systems.
Series
VM Mechanical Interlock Units
Part number
1SFN030300R1000
Product type
Mechanical interlock unit
Application
Reversing and changeover contactor interlocking
Compatible contactors
AF116..AF370, AF116B..AF370B, AX260..AX370
Mounting type
Side-by-side contactor mounting
Connection compatibility
Screw terminal contactors
Construction
Industrial insulated thermoplastic and metal mechanism
Protection function
Prevents simultaneous contactor operation
Dimensions (W × H × D)
approx. 70 × 58.7 × 31.9 mm
Weight
approx. 0.05 kg
Standards
EN 60947-4-1, UL 60947-4-1
No documents available for this product.
Delivery
We offer fast UK delivery on all stocked items. Orders placed before 3pm Monday to Friday are eligible for next-day delivery.
Standard delivery: 2–3 working days
Next-day delivery: available on in-stock items when ordered before 3pm
Express options available — contact us for details
Returns
If you need to return an item, please contact our sales team within 30 days of receipt. Items must be returned unused in their original packaging.
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● 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.
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We supply all leading manfacturers in our industry. we offer next day delivery on most poplour products.
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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.
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...
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...