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SIEMENS 3SU1050-5BF21-0AA0 Panel-Mounted Key Switch - Panel-Mounted Key Switches without Contacts
SiemensPanel-Mounted Key Switches without Contacts

SIEMENS 3SU1050-5BF21-0AA0 Panel-Mounted Key Switch

The SIEMENS Keyed Selector Switch is a panel-mounted key switch without contacts, part of the Series 3SU. It features a 2-position, maintained/maintained switch action and a key removal position on the right. This 22…

SKU 3G-OTH-32156

Also listed as: 3SU10505BF210AA0 · 3SU1050 5BF21 0AA0

Brand
Siemens
Item
3SU1050-5BF21-0AA0 Panel-Mounted Key Switch
Part Number
3SU1050-5BF21-0AA0
Category
Panel-Mounted Key Switches without Contacts
Available to Order
Also known as:3SU1050-5BF21-0AA0Siemens
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

Siemens
Manufacturer Part Number
3SU1050-5BF21-0AA0
Switch Action
Maintained/Maintained
Key Removal Position
Right

Technical Documents

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Siemens Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SIEMENS Keyed Selector Switch is a panel-mounted key switch without contacts, part of the Series 3SU. It features a 2-position, maintained/maintained switch action and a key removal position on the right. This 22 mm panel mounting size unit is identified by manufacturer part number 3SU1050-5BF21-0AA0.

Frequently Asked Questions

What is the SIEMENS 3SU1050-5BF21-0AA0 keyed selector switch used for?

This SIEMENS keyed selector switch is used for panel-mounted access control in industrial machinery, requiring a key to operate. It provides two maintained positions, ensuring secure switching in applications like machine start/stop or mode selection across manufacturing, process control, and automation systems.

What are the specifications of the SIEMENS 3SU1050-5BF21-0AA0?

The SIEMENS 3SU1050-5BF21-0AA0 is a 22 mm panel-mounted key switch without contacts. It features a maintained/maintained switch action with key removal in the right position. Part of the Series 3SU, it is designed for secure, two-position control in industrial environments.

Where to buy the SIEMENS 3SU1050-5BF21-0AA0 worldwide?

3G Electric supplies the SIEMENS 3SU1050-5BF21-0AA0 keyed selector switch worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this Series 3SU component.

How to install the SIEMENS 3SU1050-5BF21-0AA0 keyed selector switch?

Install the SIEMENS 3SU1050-5BF21-0AA0 into a 22 mm panel cutout, securing it with the provided mounting nut. Wire the switch contacts (sold separately) per your control circuit. Ensure the key is in the right removal position before operation. Follow standard industrial safety practices for panel-mounted switches.

Used in

Common applications for Siemens
District cooling plants — LME73 + RWF55 for condenser-water modulation
Inflight catering and food-processing steam boilers — LMG22 with SQN90 air-fuel cross-damper
Hospital steam-plant redundancy — LME41 with QRA2 UV flame detection for dual-fuel boilers
Semiconductor fab process heat — LME23 and SKP55 gas valves on hot-oil heater skids
Container-terminal reefer-deck heating — LMG22 retrofit onto legacy burner racks
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Siemens Products

3G Electric supplies Siemens panel-mounted key switches without contacts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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