Send a part number, a photo, or a whole BOM — we supply it and stand behind it. Worldwide shipping to 80+ countries.

3G Electric
RFQ CartGet a QuoteSign inSign up
Siemens Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp - B-Curve, 4-Pole UL1077 DIN Rail-Mount Supplementary Protectors
SiemensB-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 30XW18, MPN 5SY44256) is a B-Curve, 4-Pole UL1077 DIN Rail-Mount supplementary protector rated at 25 Amps. It features a Max. AIR Rating of 10kA at 400V AC, a DC Voltage…

SKU 3G-OTH-21599

Brand
Siemens
Item
Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp
Category
B-Curve, 4-Pole UL1077 DIN Rail-Mount Supplementary Protectors
Available to Order
Trade pricing by quote — replies within 24h
Qty
WhatsApp an engineer
No account needed — your quote request goes straight to our engineers. A free account lets you track quotes and re-order faster.
Worldwide Shipping
Air & sea freight
Datasheet on Request
Technical specs
1-Day Quote
Replies within 24h

Technical Specifications

Siemens
Manufacturer Part Number
5SY44256
Series
5SY4
Type
10kA at 400V AC, Screw Clamp, B
AC
400V
DC
72V
Max. AIR Rating
10kA at 400V AC
DC Voltage Rating
72V DC
Terminal Connection
Screw Clamp
View Full Spec Sheet

Technical Documents

No technical documents available for this product.
Request documentation →
Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.
Talk to an engineer

Ask a question

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

Product Description

The SIEMENS IEC Supplementary Protector (SKU 30XW18, MPN 5SY44256) is a B-Curve, 4-Pole UL1077 DIN Rail-Mount supplementary protector rated at 25 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, part of the 5SY4 series.

Frequently Asked Questions

What is the SIEMENS 5SY44256 supplementary protector used for?

The SIEMENS 5SY44256 is a B-Curve, 4-pole supplementary protector rated at 25 Amps. It protects branch circuits and equipment from overcurrent and short circuits in industrial control panels, HVAC systems, and machinery. Its 72V DC rating suits DC control circuits, while the 10kA interrupting capacity at 400V AC handles high-fault AC applications.

What are the specifications of the SIEMENS 5SY44256?

The SIEMENS 5SY44256 is a B-Curve, 4-pole supplementary protector rated at 25 Amps. It has a Max. AIR Rating of 10kA at 400V AC, a DC Voltage Rating of 72V DC, and a Screw Clamp terminal connection. It is part of the 5SY4 series and mounts on a DIN rail per UL1077.

Where to buy the SIEMENS 5SY44256 worldwide?

You can source the SIEMENS 5SY44256 through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we provide competitive pricing and reliable supply for this 5SY4 series supplementary protector.

How to install the SIEMENS 5SY44256 supplementary protector?

Install the SIEMENS 5SY44256 by snapping it onto a standard DIN rail. Ensure the supply is off. Connect wires to the Screw Clamp terminals, tightening to the torque specified on the device label. For DC applications, verify polarity if required. Follow local electrical codes and the manufacturer's instructions for safe operation.

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 b-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.

You might also need

Burners & Combustion →Pumps & Compressors →Spare Parts →All Products →

Similar products

Matched by specification & description
SIEMENS IEC Supplementary Protector: 13 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44136). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 13 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44136). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42256). Key specifications — Terminal Connection: Screw Clamp; AC Voltage Rating: 400V AC; Curve Type: B; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Series: 5SY4; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 25 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42256). Key specifications — Terminal Connection: Screw Clamp; AC Voltage Rating: 400V AC; Curve Type: B; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Series: 5SY4; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 10 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42106). Key specifications — Terminal Connection: Screw Clamp; AC Voltage Rating: 400V AC; Curve Type: B; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Series: 5SY4; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 10 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42106). Key specifications — Terminal Connection: Screw Clamp; AC Voltage Rating: 400V AC; Curve Type: B; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Series: 5SY4; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 40 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42406). Key specifications — Terminal Connection: Screw Clamp; AC Voltage Rating: 400V AC; Curve Type: B; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Series: 5SY4; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 40 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42406). Key specifications — Terminal Connection: Screw Clamp; AC Voltage Rating: 400V AC; Curve Type: B; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Series: 5SY4; Brand: SIEMENS.

More from Siemens

View all Siemens parts →
SIEMENS IEC Supplementary Protector: 32 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44326). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 32 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44326). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 10 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44106). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 10 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44106). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 63 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44636). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 63 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44636). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 50 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44506). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 50 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44506). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 16 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44166). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 16 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44166). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 20 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44206). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 20 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44206). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 6 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44066). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 6 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44066). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
SIEMENS IEC Supplementary Protector: 40 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44406). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.
Siemens
SIEMENS IEC Supplementary Protector: 40 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, B, 400V AC (MPN 5SY44406). Key specifications — Series: 5SY4; DC Voltage Rating: 72V DC; Max. AIR Rating: 10kA at 400V AC; Terminal Connection: Screw Clamp; Brand: SIEMENS.