Product Description

Siemens 3RB3026-1QB0 Electronic Overload Relay – 6–25 A, Class 10E

The Siemens 3RB3026-1QB0 is a microprocessor-based electronic overload relay from the Siemens SIRIUS 3RB3 series, designed for motor protection against overload, phase failure and asymmetry. It provides an adjustable current range of 6–25 A, a Class 10E trip characteristic, Size S0 construction and contactor mounting. Siemens specifies screw terminals for the main and auxiliary circuits and manual-automatic reset.

Siemens SIRIUS 3RB3 Electronic Overload Relay

The 3RB3026-1QB0 is designed to provide electronic motor protection in industrial electrical installations. Its microprocessor-based design monitors motor current and provides a defined overload response according to the selected Class 10E characteristic.

The compact S0 contactor-mounted design makes it suitable for compatible Siemens SIRIUS motor-starter assemblies.

Typical applications include:

• Industrial motors

• Pumps

• Fans and blowers

• Compressors

• Conveyors

• Machine tools

• Production equipment

• Process machinery

• Motor starters

• Industrial control panels

Adjustable 6–25 A Current Range

The 3RB3026-1QB0 has an adjustable current-setting range of 6 to 25 A, with a thermal current of 25 A.

This allows the relay to be adjusted according to the rated current of the protected motor. The current setting should be selected using the motor nameplate data and the requirements of the complete protection system.

Siemens load-feeder documentation also lists the 3RB3026-1QB0 with a 6–25 A setting range in compatible motor-starter configurations.

Class 10E Trip Characteristic

The exact 3RB3026-1QB0 is a Class 10E electronic overload relay. Siemens' product datasheet explicitly specifies the trip class as CLASS 10E.

Class 10E provides a defined overload tripping characteristic for motors with corresponding starting requirements. The selected overload class should be matched to the motor's starting time and actual operating conditions.

Electronic Overload Protection

The primary purpose of the 3RB3026-1QB0 is electronic protection against motor overload.

The relay continuously monitors motor current and responds when the configured overload characteristic is exceeded.

This can help protect motors against:

• Prolonged overcurrent

• Excessive mechanical loading

• Motor overheating caused by overload

• Abnormal operating conditions

• Excessive starting duration

Correct adjustment of the current setting is essential for effective motor protection.

Phase-Failure and Asymmetry Protection

The Siemens 3RB30 electronic overload relay family provides overload, phase-failure and asymmetry protection.

These functions are important in three-phase motor applications because phase loss or significant current imbalance can result in increased motor heating and electrical stress.

1 NO + 1 NC Auxiliary Contacts

The 3RB3026-1QB0 incorporates 1 normally closed (NC) and 1 normally open (NO) auxiliary contact. Siemens specifies the NC contact for contactor disconnection and the NO contact for the “tripped” message.

These contacts can be used for:

• Contactor-control circuits

• Trip indication

• PLC or control-panel feedback

• Alarm signalling

• Motor fault indication

• Electrical interlocking

Contactor Mounting

The 3RB3026-1QB0 is designed for contactor mounting and belongs to Size S0. Siemens specifies S0 as the overload-relay size and the compatible contactor size.

This allows the overload relay to be combined with a compatible Siemens SIRIUS contactor to create a compact motor-starter assembly.

Screw-Terminal Connections

The 3RB3026-1QB0 uses screw connections for both the main and auxiliary circuits.

This provides a conventional wiring arrangement for electrical panels, motor starters and maintenance applications.

The auxiliary circuit terminal is designed for practical connection and servicing in industrial installations.

Manual and Automatic Reset

The exact 3RB3026-1QB0 supports manual and automatic RESET. Siemens identifies the device with a Manual-Automatic-Reset configuration.

The typical recovery time after an overload trip is approximately 3 minutes with automatic reset, while manual and remote reset conditions are specified at 0 minutes under the applicable conditions.

The reset method should be selected according to the motor application and control-system requirements.

TEST Function and Self-Monitoring

The Siemens 3RB30 electronic overload-relay range includes diagnostic functions such as TEST functionality, switch-position indication and self-monitoring.

These functions can assist with:

• Commissioning

• Functional testing

• Troubleshooting

• Preventive maintenance

• Panel servicing

Electrical Characteristics

The 3RB3026-1QB0 has an insulation voltage of 690 V and a surge-voltage resistance of 6 kV. Siemens specifies approximately 1.2 W total power loss at rated current in the hot operating state, or approximately 0.4 W per pole.

The operating temperature range is specified as -25 °C to +60 °C, with the device designed for operation up to 2,000 m altitude under the applicable conditions.

Motor Applications

The 3RB3026-1QB0 is suitable for compatible motors within its 6–25 A adjustment range.

Pumps

Suitable for motor protection in pump applications against overload and phase-related abnormal conditions.

Fans and Blowers

The Class 10E characteristic can be selected for compatible motor starting requirements.

Compressors

Provides electronic overload protection for suitable compressor motors.

Conveyors

Can be incorporated into motor starters for conveyor applications.

Machine Tools

The compact S0 design is suitable for machine-control and motor-starter panels.

Production Equipment

Useful for industrial motors used in manufacturing and production machinery.

Suitable for OEMs, Panel Builders and Electrical Dealers

The 3RB3026-1QB0 is suitable for OEM equipment manufacturers, electrical panel builders, maintenance teams, industrial buyers and electrical product dealers.

For customers purchasing through SB Smart, the product is positioned as an industrial electrical component for supply and procurement, rather than as an automation-service or automation-integration product.

SB Smart can supply Siemens industrial electrical products for applications across Faridabad, Delhi NCR, Gurgaon/Gurugram, Noida, Haryana, Punjab, Mumbai and other major Indian cities.

Key Features

• Siemens SIRIUS 3RB3 electronic overload relay

• Article number 3RB3026-1QB0

• Microprocessor-based electronic overload protection

• 6–25 A adjustable current range

• Class 10E

• Size S0

• Contactor mounting

• Screw terminals for main and auxiliary circuits

• 1 NO + 1 NC auxiliary contacts

• Overload protection

• Phase-failure protection

• Asymmetry protection

• Manual RESET

• Automatic RESET

• TEST function

• Self-monitoring

• Switch-position indication

• 690 V insulation voltage

• 6 kV surge-voltage resistance

Benefits

• 6–25 A adjustable range: Suitable for a broad range of compatible industrial motors.

• Class 10E: Provides a defined overload characteristic for suitable motor-starting requirements.

• Electronic protection: Provides continuous motor-current monitoring.

• Phase protection: Helps protect against phase failure and asymmetry.

• 1 NO + 1 NC contacts: Provides control, signalling and trip-feedback functions.

• Contactor mounting: Supports compact S0 motor-starter assemblies.

• Screw terminals: Provides a familiar industrial wiring solution.

• Manual/automatic reset: Supports different motor-control requirements.

• TEST and self-monitoring: Assist commissioning and maintenance.

• Compact S0 design: Helps save control-panel space.

Why Choose Siemens 3RB3026-1QB0?

The Siemens 3RB3026-1QB0 is a compact electronic overload relay for motor protection in the 6–25 A range with a Class 10E trip characteristic. Siemens specifies S0 contactor mounting, screw connections, manual-automatic reset and 1 NO + 1 NC auxiliary contacts for this configuration.

It is a suitable choice for customers looking to buy or source Siemens motor-protection products for industrial electrical panels, motor starters, machinery and replacement requirements.

SB Smart supplies Siemens industrial electrical products and components across India, supporting procurement requirements for businesses, panel builders, maintenance departments and industrial buyers.

Delivery Across India

SB Smart supplies Siemens industrial electrical products across Faridabad, Gurgaon/Gurugram, Delhi NCR, Haryana, Noida, Punjab, Mumbai and major cities across India.

Major delivery locations include:

• Faridabad

• Delhi

• Gurgaon/Gurugram

• Delhi NCR

• Noida

• Greater Noida

• Haryana

• Punjab

• Mumbai

• Pune

• Ahmedabad

• Bengaluru

• Hyderabad

• Chennai

• Kolkata

• Jaipur

• Chandigarh

• Lucknow

• Indore

• Surat

• Vadodara

• Nagpur

• Coimbatore

• And other major cities across India

Frequently Asked Questions

1. What is Siemens 3RB3026-1QB0?

It is a Siemens SIRIUS 3RB3 electronic overload relay for motor protection with a 6–25 A adjustable current range and Class 10E trip characteristic.

2. What is the current setting range?

The adjustable current range is 6–25 A.

3. What is the trip class?

The exact 3RB3026-1QB0 is Class 10E.

4. Does it provide phase-failure protection?

Yes. The 3RB30 range provides phase-failure and asymmetry protection in addition to overload protection.

5. How many auxiliary contacts does it have?

It provides 1 NO + 1 NC auxiliary contacts. The NC contact is specified for contactor disconnection and the NO contact for the “tripped” indication.

6. Is it contactor-mounted?

Yes. The 3RB3026-1QB0 is designed for S0 contactor mounting.

7. Does it use screw terminals?

Yes. Siemens specifies screw connections for the main and auxiliary circuits.

8. What reset options are available?

It supports manual and automatic RESET.

9. Does it have diagnostic functions?

Yes. The 3RB30 range includes TEST functionality, switch-position indication and self-monitoring.

10. Where can I buy Siemens 3RB3026-1QB0 in India?

SB Smart supplies Siemens industrial electrical products in India, including Siemens SIRIUS overload relays and related motor-control components, for industrial buyers, panel builders, maintenance requirements and product procurement.