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LCN Electromagnetic Door Holder: Wall - Mounted - Electromagnetic Door Holders & Releases
LCNElectromagnetic Door Holders & Releases

LCN Electromagnetic Door Holder: Wall - Mounted

3G Electric supplies the LCN SEM7840 AL Electromagnetic Door Holder, a wall-mounted aluminum unit with a Fail Safe failure mode. We interpret customer demand and deliver genuine industrial equipment across 14…

SKU 3G-OTH-512594

Brand
LCN
Item
Electromagnetic Door Holder: Wall - Mounted
Category
Electromagnetic Door Holders & Releases
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Technical Specifications

LCN
Manufacturer Part Number
SEM7840 AL
Type
Aluminum
Failure Mode
Fail Safe
View Full Spec Sheet

Technical Documents

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

Product Description

3G Electric supplies the LCN SEM7840 AL Electromagnetic Door Holder, a wall-mounted aluminum unit with a Fail Safe failure mode. We interpret customer demand and deliver genuine industrial equipment across 14 departments—and far more—with specialist depth in combustion, pumps, and controls as an authorized distributor for brands like Schneider, ABB, Siemens, SKF, Festo, Fluke, Interpump, and FBR.

Frequently Asked Questions

What is the LCN SEM7840 AL Electromagnetic Door Holder used for?

The LCN SEM7840 AL is a wall-mounted electromagnetic door holder designed to hold fire-rated doors open under normal conditions. In a fire alarm or power loss, its Fail Safe mode releases the door to close automatically, supporting life safety and compartmentation in commercial buildings.

What are the specifications of the LCN SEM7840 AL?

The LCN SEM7840 AL is an aluminum wall-mounted electromagnetic door holder with a Fail Safe failure mode. Its manufacturer part number is SEM7840 AL. It is designed for use in fire-rated door assemblies where automatic door closing upon power interruption is required.

Where to buy the LCN SEM7840 AL worldwide?

3G Electric supplies the LCN SEM7840 AL Electromagnetic Door Holder to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this genuine LCN part.

How to install the LCN SEM7840 AL door holder?

Install the LCN SEM7840 AL on a wall at the desired door-holding position, following the manufacturer's wiring diagram for fail-safe operation. Ensure the door-mounted armature aligns with the electromagnet. Test release under power loss. For specific torque and voltage requirements, consult the LCN installation manual.

Used in

Common applications for LCN
Manufacturing quality control — LCN Force Gauge (ADA/FG) for verifying spring tension in assembly lines
Packaging industry — LCN Force Gauge for testing seal strength or compression of packaging materials
Maintenance and repair — LCN Force Gauge for checking actuation force of mechanical switches or valves
Material testing — LCN Force Gauge for measuring force in simple tensile or compressive tests on small components
Educational labs — LCN Force Gauge for demonstrating basic force measurement principles in engineering courses

LCN Products

3G Electric supplies LCN electromagnetic door holders & releases. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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