US10D3040A IMO 10kA UL1077 MCB 3 pole 40A D Curve

Q: How many poles does this circuit breaker have?

The US10D3040A is a three-pole miniature circuit breaker for three-phase electrical systems.

Q: What is the breaking capacity?

The breaker provides a 10 kA interrupting capacity for dependable fault protection.

SKU: US10D3040AMPN: US10D3040A

List Price £36.00 ex VAT

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Why Choose the IMO US10D3040A UL1077 Miniature Circuit Breaker?

The IMO US10D3040A is a high-performance UL1077 supplementary protector miniature circuit breaker (MCB) designed to provide dependable overcurrent protection for industrial control panels, OEM machinery and automation systems. Manufactured by IMO Precision Controls, this compact device delivers reliable protection while ensuring compliance with recognised international standards for industrial applications.

Designed for demanding electrical installations, the US10D3040A combines a robust construction with a high 10 kA breaking capacity, making it suitable for protecting branch circuits and control equipment against overloads and short circuits. Its compact DIN rail mounting design enables fast installation and efficient use of panel space.

Featuring a 40 A current rating, D curve tripping characteristic and three-pole configuration, the US10D3040A is ideal for circuits with high inrush current loads such as motors, transformers and industrial machinery operating on 230/400 V AC systems.

Key Advantages

Compact UL1077 supplementary protector for industrial control panels.
40 A current rating for demanding industrial circuits.
D curve characteristic suitable for high inrush current applications.
Three-pole design for three-phase circuit protection.
10 kA breaking capacity for enhanced fault protection.
DIN rail mounting allows quick installation and maintenance.

Key Features

IMO US10 series supplementary protector.
40 A rated current.
D curve tripping characteristic.
Three-pole configuration.
10 kA interrupting capacity.
Suitable for 230/400 V AC industrial systems.
DIN rail mounting for control panels.
Designed for industrial automation and machinery applications.

Reliable Protection for Industrial Electrical Systems

The IMO US10D3040A is engineered to protect industrial electrical equipment against overload and short-circuit faults. Its D curve operating characteristic allows it to tolerate the high inrush currents associated with motors, transformers and inductive loads while still providing dependable fault protection.

Its compact footprint and DIN rail mounting simplify installation within industrial control panels, helping machine builders and maintenance engineers reduce installation time while ensuring reliable long-term performance.

Typical Applications

Industrial control panels.
Motor protection circuits.
OEM machinery.
Automation systems.
Control cabinets.
Three-phase industrial electrical installations.

Technical Specifications

Current	40 A
Phase	Three Phase
Manufacturer	IMO Precision Controls
Series	US10 UL1077
Model	US10D3040A
Product type	UL1077 supplementary protector miniature circuit breaker
Rated current	40 A
Number of poles	3
Trip characteristic	D Curve
Rated voltage	230/400 V AC
Frequency	50 / 60 Hz
Breaking capacity	10 kA
Mounting type	35 mm DIN rail
Terminal capacity	1 to 25 mm²
Protection rating	IP20
Standards	UL1077, IEC/EN 60898, IEC/EN 60947-2, CE
Dimensions (H × W × D)	approx. 85.5 × 52.7 × 78 mm
Weight	approx. 0.30 kg
HS Code	8536201090
Country of Manufacture	India
Poles	3-pole
Device Type	MCB
Trip Curve	D curve
Breaking Capacity	10 kA

Frequently Asked Questions

What is the IMO US10D3040A used for?

It is a UL1077 supplementary protector designed to provide overload and short-circuit protection for industrial control circuits and machinery.

What does the D curve characteristic mean?

A D curve breaker is designed for circuits with high inrush currents, making it suitable for motors, transformers and other inductive loads.

How many poles does this circuit breaker have?

The US10D3040A is a three-pole miniature circuit breaker for three-phase electrical systems.

What is the breaking capacity?

The breaker provides a 10 kA interrupting capacity for dependable fault protection.

How is the breaker installed?

The unit mounts directly onto a standard 35 mm DIN rail inside industrial electrical control panels.

Trusted by Industrial Control Professionals

IMO Precision Controls circuit protection products are trusted by panel builders, machine manufacturers and automation engineers worldwide for dependable electrical protection, easy installation and reliable long-term performance.

UK delivery

Delivery options

Free UK delivery on orders over £200 ex VAT. Order in-stock items before 2pm Monday to Friday for next-day delivery.

This product Lead time on request

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Standard delivery

£8 ex VAT · free over £200

UK parcel delivery is £8 ex VAT, or free on orders over £200 ex VAT.

Heavier items may be charged at a weight-based or pallet rate, shown at checkout.

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Order and pay online, then collect from our showroom.

Please allow 15–30 minutes after ordering for us to prepare your order.

Northern Ireland, ROI & export

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Delivery is calculated at checkout based on your destination.

Orders with mixed availability

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Need the in-stock items sooner? Ask us and we can split the delivery.

Business customer returns

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Need to return an item? Find the guidance for your order below, then contact our team before sending anything back.

Stocked items

Request within 30 days

Changed your mind or ordered the wrong item? Request a return within 30 days of receipt. There is no restocking charge.

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Faulty, damaged on delivery or the wrong product supplied? Contact our team as soon as possible with the details.

We will review the issue and arrange an appropriate resolution under our terms and conditions and your statutory rights.

Made-to-order items

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Manufactured, configured and special-order products can only be returned with the manufacturer’s approval. Any handling charge is agreed with you when you request the return.

This does not affect claims for faulty goods or items that do not meet the agreed specification.

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Send your order number, product details and reason for return. For faults or delivery damage, include photographs if available. We will confirm the next steps.

Email returns team 01706 242050

The 30-day return request period applies to change-of-mind returns for stocked items. It does not limit your statutory rights for faulty or non-conforming goods.

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