ABB 1SFN034700R1000 VM300H is a mechanical interlock unit that prevents simultaneous operation of two compatible horizontally mounted AC-operated or DC-operated contactors.
£32.57
The ABB 1SFN034700R1000, manufacturer designation VM300H, is a purpose-designed mechanical interlock unit used to interlock two horizontally mounted contactors. It mechanically prevents both contactors from closing simultaneously, supporting safe and dependable operation in reversing, changeover and transfer-control circuits.
As a genuine ABB contactor accessory, the VM300H is designed for direct mechanical coordination between compatible contactors. Its purely mechanical interlocking action does not depend on the contactor control voltage, allowing it to work with both AC-operated and DC-operated contactors.
The VM300H can mechanically interlock two compatible contactors of the same or different ratings when installed according to ABB’s contactor compatibility tables. Its horizontal mounting arrangement makes it suitable for coordinated switching assemblies where simultaneous contactor operation must be prevented.
Mechanical interlocks create a physical link between two contactors so that closing one contactor prevents the other from closing. This provides an additional layer of protection in circuits where simultaneous switching could cause conflicting phase connections or unsafe equipment operation.
The ABB VM300H is suited to reversing starters, electrical changeover systems and other coordinated switching arrangements. It can complement electrical interlocking within the control circuit while continuing to provide physical contactor separation independently of the control supply.
| Manufacturer | ABB |
|---|---|
| Series | VM300H |
| Model | VM300H |
| Order code | 1SFN034700R1000 |
| Product type | Mechanical interlock unit |
| Interlocked devices | 2 contactors |
| Mounting arrangement | Horizontal |
| Operating principle | Mechanical interlocking |
| Contactor operation | AC or DC operated |
| Suitable for | Compatible ABB contactors according to the manufacturer’s selection table |
| Product net weight | 0.15 kg |
The ABB VM300H mechanically interlocks two horizontally mounted contactors so that they cannot close simultaneously.
The VM300H is designed to mechanically interlock two compatible contactors.
Yes. The VM300H can be used with compatible AC-operated or DC-operated contactors.
Yes. Contactors of the same or different ratings can be interlocked when the combination is approved in ABB’s compatibility tables.
The VM300H is designed for an assembly in which the two compatible contactors are mounted horizontally.
ABB mechanical interlock units provide dependable physical coordination between compatible contactors, helping prevent conflicting switching states in industrial motor-control and changeover 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.
● frequently asked questions
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.
We supply all leading manfacturers in our industry. we offer next day delivery on most poplour products.
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.
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.
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.
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
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...