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Siemens Mechanical Interlock: Mechanical Interlock - Siemens Circuit Breaker Locks & Padlocks
SiemensSiemens Circuit Breaker Locks & Padlocks

Siemens Mechanical Interlock: Mechanical Interlock

The Siemens Mechanical Interlock (MPN ECQML12) is a circuit breaker lock and padlock accessory designed for use with Siemens BQ Circuit Breakers. This mechanical interlock provides a physical locking mechanism to…

SKU 3G-OTH-23377

Also listed as: ECQML 12 · ECQML-12

Brand
Siemens
Item
Mechanical Interlock: Mechanical Interlock
Category
Siemens Circuit Breaker Locks & Padlocks
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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
ECQML12
For Use With
Siemens BQ Circuit Breakers
Product Type
Mechanical Interlock

Technical Documents

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

Product Description

The Siemens Mechanical Interlock (MPN ECQML12) is a circuit breaker lock and padlock accessory designed for use with Siemens BQ Circuit Breakers. This mechanical interlock provides a physical locking mechanism to prevent unauthorized operation or accidental switching of the breaker.

Frequently Asked Questions

What is the Siemens ECQML12 mechanical interlock used for?

The Siemens ECQML12 mechanical interlock is a circuit breaker accessory that physically locks Siemens BQ circuit breakers to prevent unauthorized operation or accidental switching. It is commonly used in industrial electrical panels, commercial buildings, and maintenance lockout/tagout (LOTO) safety procedures.

What are the specifications of the Siemens ECQML12 mechanical interlock?

The Siemens ECQML12 is a mechanical interlock designed for use with Siemens BQ circuit breakers. Its product type is mechanical interlock, and the manufacturer part number is ECQML12. It provides a physical locking mechanism to secure the breaker handle, enhancing safety during maintenance or isolation tasks.

Where to buy the Siemens ECQML12 mechanical interlock worldwide?

You can source the Siemens ECQML12 mechanical interlock through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we supply genuine Siemens accessories for industrial applications.

How to install the Siemens ECQML12 mechanical interlock on a BQ breaker?

To install the Siemens ECQML12, first ensure the BQ circuit breaker is in the OFF position. Align the interlock with the breaker handle mounting holes, then secure it using the provided hardware. The interlock will physically block handle movement when locked. Always follow Siemens installation instructions and local safety codes.

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

Siemens Products

3G Electric supplies Siemens siemens circuit breaker locks & padlocks. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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