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Siemens Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp - C-Curve, 4-Pole UL1077 DIN Rail-Mount Supplementary Protectors
SiemensC-Curve, 4-Pole UL1077 DIN Rail-Mount Supplementary Protectors

Siemens Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp

The SIEMENS IEC Supplementary Protector (SKU 30XW19, MPN 5SY44257) is a C-Curve, 4-Pole UL1077 DIN Rail-Mount supplementary protector rated at 25 A Amps. It features a Max. AIR Rating of 10kA at 400V AC, a DC Voltage…

SKU 3G-OTH-20486

Brand
Siemens
Item
Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp
Category
C-Curve, 4-Pole UL1077 DIN Rail-Mount Supplementary Protectors
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Technical Specifications

Siemens
Manufacturer Part Number
5SY44257
Series
5SY4
Type
10kA at 400V AC, Screw Clamp, C
AC
400V
DC
72V
Max. AIR Rating
10kA at 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 IEC Supplementary Protector (SKU 30XW19, MPN 5SY44257) is a C-Curve, 4-Pole UL1077 DIN Rail-Mount supplementary protector rated at 25 A Amps. It features a Max. AIR Rating of 10kA at 400V AC, a DC Voltage Rating of 72V DC, and a Screw Clamp terminal connection. This device is part of the 5SY4 series and is designed for overcurrent protection in industrial applications.

Frequently Asked Questions

What is the SIEMENS 5SY44257 supplementary protector used for?

The SIEMENS 5SY44257 is a C-curve, 4-pole UL1077 DIN rail-mount supplementary protector rated at 25 A. It provides overcurrent protection in industrial control panels, machinery, and automation systems where branch-circuit protection is not required. Its 72V DC rating suits DC control circuits.

What are the specifications of the SIEMENS 5SY44257?

The SIEMENS 5SY44257 (MPN 5SY44257) is a 25 A, 4-pole supplementary protector with a C-curve trip characteristic. It has a max. AIR rating of 10kA at 400V AC, a DC voltage rating of 72V DC, and screw clamp terminals. It is part of the 5SY4 series and mounts on a DIN rail.

Where to buy the SIEMENS 5SY44257 worldwide?

3G Electric supplies the SIEMENS 5SY44257 supplementary protector to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this genuine Siemens component.

How to install a SIEMENS 5SY4 series supplementary protector?

Install the SIEMENS 5SY4 series protector by snapping it onto a standard 35 mm DIN rail. Ensure the supply is de-energized. Connect conductors to the screw clamp terminals per the torque rating on the device label. Follow local electrical codes and the manufacturer's instructions for proper overcurrent protection.

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 c-curve, 4-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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