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Siemens Overload Relay: Electronic Protection, 3 Poles, 1NO/1NC, Frame Size A1 - IEC Electronic Overload Relays
SiemensIEC Electronic Overload Relays

Siemens Overload Relay: Electronic Protection, 3 Poles, 1NO/1NC, Frame Size A1

The SIEMENS Overload Relay: Electronic Protection is an IEC electronic overload relay with a frame size of A1, designed for use with Class 14 Starters and compatible contactors of the same frame size. It features a…

SKU 3G-OTH-44909

Brand
Siemens
Item
Overload Relay: Electronic Protection, 3 Poles, 1NO/1NC, Frame Size A1
Category
IEC Electronic Overload Relays
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Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
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Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

Siemens
Manufacturer Part Number
3UB81234EW2
Type
1NO/1NC, Frame Size A1, 10 A – 40 A
Poles
3
Frame Size
A1
Compatible Contactors
Frame Size A1
Auxiliary Contact Form
1NO/1NC
Maximum Voltage Rating
690V AC
Thermal Units Required
Not Applicable to Electronic Type Overload Relays
Terminal Connection Type
Screw Terminals
Compatible Contactor Series
Class 14 Starters

Technical Documents

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

Product Description

The SIEMENS Overload Relay: Electronic Protection is an IEC electronic overload relay with a frame size of A1, designed for use with Class 14 Starters and compatible contactors of the same frame size. It features a 1NO/1NC auxiliary contact form, screw terminals, and a maximum voltage rating of 690V AC. This three-pole relay covers a current range of 10 A to 40 A and does not require thermal units, as it is an electronic type.

Frequently Asked Questions

What is the SIEMENS 3UB81234EW2 overload relay used for?

The SIEMENS 3UB81234EW2 is an IEC electronic overload relay used to protect motors from overcurrent and phase loss in industrial applications. It is designed for use with Class 14 starters and compatible contactors of frame size A1, making it suitable for pump, fan, and conveyor systems.

What are the specifications of the SIEMENS 3UB81234EW2 overload relay?

The SIEMENS 3UB81234EW2 is a three-pole electronic overload relay with a frame size A1, current range 10 A to 40 A, and maximum voltage rating 690V AC. It features 1NO/1NC auxiliary contacts, screw terminals, and does not require thermal units. It is compatible with Class 14 starters and frame size A1 contactors.

Where to buy the SIEMENS 3UB81234EW2 overload relay worldwide?

You can source the SIEMENS 3UB81234EW2 overload relay worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time; we provide reliable sourcing for Siemens components.

How to select the correct SIEMENS overload relay for a motor?

To select the correct SIEMENS overload relay, match the relay's current range (e.g., 10 A to 40 A for the 3UB81234EW2) to the motor's full-load current. Ensure the frame size (A1) matches your contactor and starter series (Class 14). For electronic types, no thermal units are needed; set the dial to the motor's FLA.

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 iec electronic overload relays. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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