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Siemens 5SY42457 C-Curve 2-Pole UL1077 Supplementary Protector - C-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors
SiemensC-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors

Siemens 5SY42457 C-Curve 2-Pole UL1077 Supplementary Protector

The Siemens 5SY4 series IEC Supplementary Protector (SKU 3G-OTH-21165) is a C-curve, 2-pole UL1077 DIN rail-mount supplementary protector rated at 45 A. It features a maximum AIR rating of 10 kA at 400 V AC, AC…

SKU 3G-OTH-21165

Brand
Siemens
Item
5SY42457 C-Curve 2-Pole UL1077 Supplementary Protector
Part Number
5SY42457
Category
C-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors
Available to Order
Also known as:5SY42457Siemens
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Technical Specifications

Siemens
Manufacturer Part Number
5SY42457
Series
5SY4
Type
10kA at 400V AC, Screw Clamp, 5SY4
AC
400V
DC
72V
Curve Type
C
Max. AIR Rating
10kA at 400V AC
AC Voltage Rating
400V AC
DC Voltage Rating
72V DC
Terminal Connection
Screw Clamp

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

Product Description

The Siemens 5SY4 series IEC Supplementary Protector (SKU 3G-OTH-21165) is a C-curve, 2-pole UL1077 DIN rail-mount supplementary protector rated at 45 A. It features a maximum AIR rating of 10 kA at 400 V AC, AC voltage rating of 400 V AC, and DC voltage rating of 72 V DC, with screw clamp terminals.

Frequently Asked Questions

What is the Siemens 5SY42457 supplementary protector used for?

The Siemens 5SY42457 is a C-curve, 2-pole UL1077 DIN rail-mount supplementary protector rated at 45 A. It protects industrial control circuits, HVAC equipment, and motor starters from overcurrents and short circuits in panel boards and machinery across 14 industrial departments.

What are the specifications of the Siemens 5SY42457?

The Siemens 5SY42457 is a 45 A, 2-pole supplementary protector with a C-curve, rated 400V AC and 72V DC. It has a maximum AIR rating of 10kA at 400V AC and uses screw clamp terminals. It is part of the 5SY4 series and complies with UL1077.

Where to buy the Siemens 5SY42457 worldwide?

3G Electric supplies the Siemens 5SY42457 supplementary protector 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 and other Siemens circuit protection components.

How to install the Siemens 5SY42457 on a DIN rail?

To install the Siemens 5SY42457, snap it onto a standard 35 mm DIN rail. Ensure the rail is clean and the protector is oriented correctly. Tighten the screw clamp terminals to the manufacturer's recommended torque. Always de-energize the circuit before installation and follow local electrical 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
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Siemens Products

3G Electric supplies Siemens c-curve, 2-pole ul1077 din rail-mount supplementary protectors. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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C-curve, 2-pole supplementary protector rated 1 A, 400V AC, with a maximum interrupting rating of 5kA at 400V AC. Features screw clamp terminals and mounts on DIN rail. Suitable for overcurrent and short-circuit protection in branch circuits and equipment
Siemens
C-curve, 2-pole supplementary protector rated 1 A, 400V AC, with a maximum interrupting rating of 5kA at 400V AC. Features screw clamp terminals and mounts on DIN rail. Suitable for overcurrent and short-circuit protection in branch circuits and equipment

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