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SIEMENS IEC 5SY44028 D-Curve 4-Pole UL1077 Supplementary Protector - D-Curve, 4-Pole UL1077 DIN Rail-Mount Supplementary Protectors
SIEMENS IECD-Curve, 4-Pole UL1077 DIN Rail-Mount Supplementary Protectors

SIEMENS IEC 5SY44028 D-Curve 4-Pole UL1077 Supplementary Protector

The SIEMENS IEC Supplementary Protector (MPN 5SY44028) is a D-Curve, 4-Pole UL1077 DIN Rail-Mount supplementary protector rated at 2 Amps. It features a 72V DC rating and a 10kA interrupting capacity at 400V AC, with…

SKU 3G-OTH-154292

Brand
SIEMENS IEC
Item
5SY44028 D-Curve 4-Pole UL1077 Supplementary Protector
Category
D-Curve, 4-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 IEC
Manufacturer Part Number
5SY44028
Type
10kA at 400V AC, Screw Clamp, D
AC
400V
DC
72V

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

Product Description

The SIEMENS IEC Supplementary Protector (MPN 5SY44028) is a D-Curve, 4-Pole UL1077 DIN Rail-Mount supplementary protector rated at 2 Amps. It features a 72V DC rating and a 10kA interrupting capacity at 400V AC, with Screw Clamp terminals. This 5SY4 series device is designed for overcurrent protection in industrial control panels and equipment.

Frequently Asked Questions

What is the SIEMENS IEC Supplementary Protector 5SY44028 used for?

The SIEMENS IEC Supplementary Protector 5SY44028 provides overcurrent protection for industrial control panels and equipment. Its D-Curve trip characteristic makes it suitable for loads with high inrush currents, such as motors and transformers, in commercial and industrial applications.

What are the specifications of the SIEMENS 5SY44028 supplementary protector?

The SIEMENS 5SY44028 is a 4-pole, D-Curve supplementary protector rated at 2 Amps with a 72V DC rating and 10kA interrupting capacity at 400V AC. It features Screw Clamp terminals, mounts on a DIN rail, and complies with UL1077 standards.

Where to buy the SIEMENS 5SY44028 supplementary protector worldwide?

You can source the SIEMENS 5SY44028 supplementary protector through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations, ensuring reliable supply for your projects.

How to install the SIEMENS 5SY44028 supplementary protector?

Install the SIEMENS 5SY44028 by snapping it onto a DIN rail. Ensure the circuit is de-energized, then connect wires to the Screw Clamp terminals using the specified torque. Follow standard electrical safety practices and consult the manufacturer's datasheet for detailed wiring diagrams.

Used in

Common applications for SIEMENS IEC
Motor control centers — Siemens 5SY4 D-curve supplementary protectors (e.g., 5SY42108) for motor branch circuit protection
HVAC equipment — A-curve protectors (e.g., 5SY42255) for compressor and fan motor overcurrent protection
Industrial conveyor systems — 4-pole D-curve protectors (e.g., 5SY44168) for three-phase motor protection with neutral
Pump control panels — 2-pole supplementary protectors (e.g., 5SY42038) for single-phase pump motor protection
Machine tool control circuits — A-curve protectors (e.g., 5SY44155) for solenoid valve and relay protection
Power distribution sub-panels — 4-pole protectors (e.g., 5SY44155) for three-phase branch circuit protection in light industrial settings

SIEMENS IEC Products

3G Electric supplies SIEMENS IEC d-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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Compatible alternatives & equivalents

Cross-referenced by specification & description
4-pole D-curve supplementary protector rated 4 A, 400 V AC / 72 V DC, with 10 kA breaking capacity at 400 V AC. Screw clamp terminals. UL1077 listed for branch-circuit protection in industrial control panels, HVAC, and automation systems. DIN rail mount
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4-pole D-curve supplementary protector rated 4 A, 400 V AC / 72 V DC, with 10 kA breaking capacity at 400 V AC. Screw clamp terminals. UL1077 listed for branch-circuit protection in industrial control panels, HVAC, and automation systems. DIN rail mount
D-Curve, 4-pole UL1077 supplementary protector rated 10 A, 400 V AC, 72 V DC. Interrupting capacity 10 kA at 400 V AC. Screw clamp terminals. For DIN rail mounting. Used for overcurrent and short-circuit protection in control circuits and equipment
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D-Curve, 4-pole UL1077 supplementary protector rated 10 A, 400 V AC, 72 V DC. Interrupting capacity 10 kA at 400 V AC. Screw clamp terminals. For DIN rail mounting. Used for overcurrent and short-circuit protection in control circuits and equipment
D-Curve, 4-pole UL1077 supplementary protector rated 0.5 A with screw clamp terminals. Breaking capacity 10kA at 400V AC, voltage rating 72V DC. For DIN rail mounting in control panels and automation systems where branch-circuit protection is not required
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D-Curve, 4-pole UL1077 supplementary protector rated 0.5 A with screw clamp terminals. Breaking capacity 10kA at 400V AC, voltage rating 72V DC. For DIN rail mounting in control panels and automation systems where branch-circuit protection is not required
4-pole D-curve supplementary protector rated 63 A, 400V AC and 72V DC, with 10kA interrupting capacity at 400V AC. Screw clamp terminals. UL1077 listed for overcurrent protection in control panels, HVAC, and machinery
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4-pole D-curve supplementary protector rated 63 A, 400V AC and 72V DC, with 10kA interrupting capacity at 400V AC. Screw clamp terminals. UL1077 listed for overcurrent protection in control panels, HVAC, and machinery
This 4-pole supplementary protector features a D-curve trip characteristic for overcurrent protection in circuits with high inrush loads. Rated 16 A, 400V AC and 72V DC, with a 10kA interrupting capacity at 400V AC. Screw clamp terminals facilitate wiring. Suitable for DIN rail mounting in control panels and equipment
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This 4-pole supplementary protector features a D-curve trip characteristic for overcurrent protection in circuits with high inrush loads. Rated 16 A, 400V AC and 72V DC, with a 10kA interrupting capacity at 400V AC. Screw clamp terminals facilitate wiring. Suitable for DIN rail mounting in control panels and equipment
40 A, D-curve, 4-pole supplementary protector from the 5SY4 series. Rated 72V DC and 10kA at 400V AC with screw clamp terminals. UL1077 listed for DIN rail mounting. Used for overcurrent protection in industrial control panels, HVAC equipment, and machinery where high inrush loads occur
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40 A, D-curve, 4-pole supplementary protector from the 5SY4 series. Rated 72V DC and 10kA at 400V AC with screw clamp terminals. UL1077 listed for DIN rail mounting. Used for overcurrent protection in industrial control panels, HVAC equipment, and machinery where high inrush loads occur

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D-Curve, 4-pole supplementary protector rated 32 A with screw clamp terminals. Interrupting capacity 10 kA at 400 V AC. For overcurrent and short-circuit protection of industrial control circuits and equipment in panel building and machinery applications
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This 4-pole supplementary protector from the 5SY4 series features a D tripping curve and is rated 50 A, 400V AC (10kA interrupting capacity) and 72V DC. It uses screw clamp terminals and mounts on a standard DIN rail. Suitable for overcurrent and short-circuit protection in industrial control circuits and equipment
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This 4-pole supplementary protector with D-curve trip characteristic is rated 25 A, 400 V AC and 72 V DC, with a breaking capacity of 10 kA at 400 V AC. It features screw clamp terminals and is designed for DIN rail mounting. Typical applications include overcurrent and short-circuit protection of industrial control circuits and equipment
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This 4-pole supplementary protector with D-curve trip characteristic is rated 25 A, 400 V AC and 72 V DC, with a breaking capacity of 10 kA at 400 V AC. It features screw clamp terminals and is designed for DIN rail mounting. Typical applications include overcurrent and short-circuit protection of industrial control circuits and equipment
D-Curve, 4-pole supplementary protector rated 13 A, 400 V AC / 72 V DC with 10 kA breaking capacity at 400 V AC. Screw clamp terminals. UL1077 listed for DIN rail mounting. Suitable for overcurrent and short-circuit protection in industrial control circuits, panel boards, and automation systems
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D-Curve, 4-pole supplementary protector rated 13 A, 400 V AC / 72 V DC with 10 kA breaking capacity at 400 V AC. Screw clamp terminals. UL1077 listed for DIN rail mounting. Suitable for overcurrent and short-circuit protection in industrial control circuits, panel boards, and automation systems
This 4-pole supplementary protector features a D-curve trip characteristic for overcurrent protection in industrial control panels and equipment. Rated 8 A at 400V AC and 72V DC with a 10kA interrupting capacity at 400V AC, it uses screw clamp terminals for secure wiring. Suitable for DIN rail mounting, it provides branch circuit protection in automation and power distribution systems
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This 4-pole supplementary protector features a D-curve trip characteristic for overcurrent protection in industrial control panels and equipment. Rated 8 A at 400V AC and 72V DC with a 10kA interrupting capacity at 400V AC, it uses screw clamp terminals for secure wiring. Suitable for DIN rail mounting, it provides branch circuit protection in automation and power distribution systems
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D-Curve 4-pole supplementary protector rated 1A, 400V AC and 72V DC, with 10kA interrupting capacity at 400V AC. Screw clamp terminals. UL1077 listed. Suitable for overcurrent protection in industrial control circuits and loads with high inrush currents
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