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Siemens 5SY42506 B-Curve 2-Pole Supplementary Protector - B-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors
SiemensB-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors

Siemens 5SY42506 B-Curve 2-Pole Supplementary Protector

The SIEMENS IEC Supplementary Protector (SKU 5SY42506, MPN 5SY42506) is a B-Curve, 2-Pole UL1077 DIN Rail-Mount supplementary protector rated at 50 A Amps. It features a Max. AIR Rating of 10kA at 400V AC, AC Voltage…

SKU 3G-OTH-21963

Brand
Siemens
Item
5SY42506 B-Curve 2-Pole Supplementary Protector
Category
B-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

Siemens
Manufacturer Part Number
5SY42506
Series
5SY4
Type
10kA at 400V AC, Screw Clamp, 5SY4
AC
400V
DC
72V
Curve Type
B
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 5SY42506, MPN 5SY42506) is a B-Curve, 2-Pole UL1077 DIN Rail-Mount supplementary protector rated at 50 A Amps. It features a Max. AIR Rating of 10kA at 400V AC, AC Voltage Rating of 400V AC, and DC Voltage Rating of 72V DC, with a Screw Clamp terminal connection from the 5SY4 series.

Frequently Asked Questions

What is the SIEMENS 5SY42506 supplementary protector used for?

The SIEMENS 5SY42506 is a B-curve, 2-pole supplementary protector rated at 50 A. It protects branch circuits and sensitive equipment against overloads and short circuits in industrial control panels, HVAC systems, and automation applications where UL1077 listing is required.

What are the specifications of the SIEMENS 5SY42506?

The SIEMENS 5SY42506 is a 50 A, 2-pole supplementary protector with a B-curve. It has an AC voltage rating of 400 V AC, a DC voltage rating of 72 V DC, and a maximum AIR rating of 10 kA at 400 V AC. Terminal connection is screw clamp, and it is part of the 5SY4 series.

Where to buy the SIEMENS 5SY42506 worldwide?

You can source the SIEMENS 5SY42506 supplementary protector 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.

How to install the SIEMENS 5SY42506 supplementary protector?

Install the SIEMENS 5SY42506 on a DIN rail by snapping it into place. Ensure the circuit is de-energized. Connect wires to the screw clamp terminals per the torque specifications in the datasheet. Verify polarity for DC applications. 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 b-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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Compatible alternatives & equivalents

Cross-referenced by specification & description
SIEMENS IEC Supplementary Protector: 16 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42166)
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SIEMENS IEC Supplementary Protector: 16 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42166)
This B-curve, 1-pole supplementary protector from the Siemens 5SY4 series is rated at 16 A with a maximum air rating of 10kA at 230/400V AC and a DC voltage rating of 72V. It features screw clamp terminals and is designed for DIN-rail mounting. Typical applications include protection of branch circuits and sensitive equipment in industrial control panels, HVAC systems, and lighting circuits
Siemens
This B-curve, 1-pole supplementary protector from the Siemens 5SY4 series is rated at 16 A with a maximum air rating of 10kA at 230/400V AC and a DC voltage rating of 72V. It features screw clamp terminals and is designed for DIN-rail mounting. Typical applications include protection of branch circuits and sensitive equipment in industrial control panels, HVAC systems, and lighting circuits
This 1-pole supplementary protector from the Siemens 5SY4 series features a B-curve trip characteristic and a rated current of 50 A. It provides overcurrent protection for downstream equipment in applications such as industrial control panels, HVAC systems, and lighting circuits. The unit is UL1077 listed for branch-circuit use and mounts on a DIN rail. Terminal connection is via screw clamp
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This 1-pole supplementary protector from the Siemens 5SY4 series features a B-curve trip characteristic and a rated current of 50 A. It provides overcurrent protection for downstream equipment in applications such as industrial control panels, HVAC systems, and lighting circuits. The unit is UL1077 listed for branch-circuit use and mounts on a DIN rail. Terminal connection is via screw clamp
B-curve, 1-pole supplementary protector rated 63 A with screw clamp terminals. Provides overcurrent protection for branch circuits and equipment in industrial control panels, HVAC systems, and lighting applications. Rated 10kA at 230/400V AC and 72V DC. DIN rail mount, UL1077 listed
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B-curve, 1-pole supplementary protector rated 63 A with screw clamp terminals. Provides overcurrent protection for branch circuits and equipment in industrial control panels, HVAC systems, and lighting applications. Rated 10kA at 230/400V AC and 72V DC. DIN rail mount, UL1077 listed
B-curve, 1-pole supplementary protector rated 6 A, with a maximum AIR rating of 10kA at 230/400V AC and DC voltage rating of 72V DC. Features screw clamp terminals and DIN rail mounting. Suitable for overcurrent protection in industrial control panels and equipment where branch-circuit protection is not required
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B-curve, 1-pole supplementary protector rated 6 A, with a maximum AIR rating of 10kA at 230/400V AC and DC voltage rating of 72V DC. Features screw clamp terminals and DIN rail mounting. Suitable for overcurrent protection in industrial control panels and equipment where branch-circuit protection is not required

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B-curve, 2-pole supplementary protector rated 10 A, 400V AC and 72V DC with a maximum interrupting rating of 10kA at 400V AC. Features screw clamp terminals and is designed for DIN-rail mounting. Suitable for overload and short-circuit protection in branch circuits and control panels
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B-curve, 2-pole supplementary protector rated 10 A, 400V AC and 72V DC with a maximum interrupting rating of 10kA at 400V AC. Features screw clamp terminals and is designed for DIN-rail mounting. Suitable for overload and short-circuit protection in branch circuits and control panels
B-curve, 2-pole supplementary protector rated 25 A with screw clamp terminals. AC voltage rating 400 V AC, DC voltage rating 72 V DC, maximum interrupting rating 10 kA at 400 V AC. Suitable for overload and short-circuit protection in branch circuits, control panels, and equipment
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B-curve, 2-pole supplementary protector rated 25 A with screw clamp terminals. AC voltage rating 400 V AC, DC voltage rating 72 V DC, maximum interrupting rating 10 kA at 400 V AC. Suitable for overload and short-circuit protection in branch circuits, control panels, and equipment
SIEMENS IEC Supplementary Protector: 63 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42636)
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SIEMENS IEC Supplementary Protector: 63 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42636)
SIEMENS IEC Supplementary Protector: 32 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42326)
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SIEMENS IEC Supplementary Protector: 32 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42326)
SIEMENS IEC Supplementary Protector: 20 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42206)
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SIEMENS IEC Supplementary Protector: 20 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42206)
SIEMENS IEC Supplementary Protector: 6 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42066)
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SIEMENS IEC Supplementary Protector: 6 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42066)
SIEMENS IEC Supplementary Protector: 40 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42406)
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SIEMENS IEC Supplementary Protector: 40 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42406)
SIEMENS IEC Supplementary Protector: 13 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42136)
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SIEMENS IEC Supplementary Protector: 13 A Amps, 72V DC, 10kA at 400V AC, Screw Clamp, 5SY4, 400V AC (MPN 5SY42136)