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Siemens Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp - C-Curve, 3-Pole UL1077 DIN Rail-Mount Supplementary Protectors
SiemensC-Curve, 3-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 30XU14, MPN 5SY43257) is a 25 A, C-Curve, 3-Pole UL1077 DIN Rail-Mount supplementary protector from the 5SY4 series. It is rated for 400V AC and 72V DC, with a maximum AIR…

SKU 3G-OTH-19831

Brand
Siemens
Item
Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp
Category
C-Curve, 3-Pole UL1077 DIN Rail-Mount Supplementary Protectors
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Technical Specifications

Siemens
Manufacturer Part Number
5SY43257
Series
5SY4
Type
10kA at 400V AC, Screw Clamp, 5SY4
AC
400V
DC
72V
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 IEC Supplementary Protector (SKU 30XU14, MPN 5SY43257) is a 25 A, C-Curve, 3-Pole UL1077 DIN Rail-Mount supplementary protector from the 5SY4 series. It is rated for 400V AC and 72V DC, with a maximum AIR rating of 10kA at 400V AC, and features a screw clamp terminal connection.

Frequently Asked Questions

What is the SIEMENS 5SY43257 supplementary protector used for?

The SIEMENS 5SY43257 is a 25 A, C-Curve, 3-pole UL1077 supplementary protector designed to protect branch circuits and control equipment from overloads and short circuits. It is commonly used in industrial control panels, HVAC systems, and machinery across 14 industrial departments, including electrical and power transmission.

What are the specifications of the SIEMENS 5SY43257?

The SIEMENS 5SY43257 is a 25 A, C-Curve, 3-pole supplementary protector from the 5SY4 series. It is rated for 400V AC and 72V DC, with a maximum AIR rating of 10kA at 400V AC. Terminal connection is screw clamp, and it mounts on a DIN rail per UL1077.

Where to buy the SIEMENS 5SY43257 in worldwide?

3G Electric supplies the SIEMENS 5SY43257 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 and other Siemens circuit protection components.

How to install the SIEMENS 5SY43257 supplementary protector?

Install the SIEMENS 5SY43257 by snapping it onto a standard 35 mm DIN rail. Ensure the circuit is de-energized, then connect phase conductors to the screw clamp terminals using the correct torque specified on the device label. Verify polarity for DC applications and test operation after installation.

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, 3-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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SIEMENS IEC Supplementary Protector: 80 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY43807). Key specifications — Terminal Connection: Screw Clamp; Series: 5SY4; AC Voltage Rating: 400V AC; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Brand: SIEMENS.
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SIEMENS IEC Supplementary Protector: 80 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY43807). Key specifications — Terminal Connection: Screw Clamp; Series: 5SY4; AC Voltage Rating: 400V AC; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Brand: SIEMENS.