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Siemens REF3B020 EF3B020 - 20A 3 Pole Molded Case Circuit Breaker

  • 20A
  • 3 Pole
  • Bolt-On
Siemens REF3B020
EF3B020 - 20A 3 Pole Molded Case Circuit Breaker
Brand Siemens
SKU REF3B020
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  • 20A
  • 3 Pole
  • Bolt-On

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Siemens EF3B020 - 20A 3 Pole Molded Case Circuit Breaker

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$415.25 No Stock

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Description

A drop-in replacement for older systems, the Siemens REF3B020 is a 20A, 3-pole molded case circuit breaker. It features a fixed thermal-magnetic trip unit with long-time and instantaneous functions to ensure reliable commercial and industrial circuit protection. Designed for bolt-on installation, it fits legacy Siemens and ITE panelboards and motor control centers. It replaces the EF3B020. This E-Frame breaker handles up to 600VAC and 250VDC, delivering 14kAIC at 480VAC.

Specifications

Key specifications
Brand Siemens
Part Number REF3B020-R
Series EF Frame
Amperage 20A
Poles 3
Mounting Style Bolt-On
Voltage 240VAC, 480VAC, 600VAC, 250VDC
Phase 3
AIC Rating 18kA @ 240VAC, 14kA @ 480VAC, 14kA @ 600VAC, 10kA @ 250VDC
Fit and installation
Terminal Type Lugs
For Use With Siemens/ITE Panelboards, Motor Control Centers
Wire Gauge 14-1/0 AWG (Cu), 12-1/0 AWG (Al)
Max Wire 1/0 AWG
Min Wire 14 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed Thermal, Fixed Magnetic
Standards and features
Available Options Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch
Accessories Load Side Lugs
Standards CSA C22.2 No. 5, NEMA AB-1, UL 489
Approval CSA, UL
Temp Rating 40C
Construction Features Non-Interchangeable Trip

Product FAQs

5 answers
What is the modern replacement for the legacy EF3B020 circuit breaker?

The EF3B020 is a legacy EF frame breaker. For system upgrades or new installations, it is typically replaced by the modern Siemens ED63B020 molded case circuit breaker.

Which specific enclosures and panelboards are compatible with the EF3B020?

In addition to standard Siemens and I-T-E motor control centers, this bolt-on breaker installs directly into legacy FC-1 panelboards and FC-20 switchboards.

Is the EF3B020 breaker HACR rated for HVAC applications?

Yes, this breaker carries an HACR rating, meaning it is tested and approved for use with commercial heating, air conditioning, and refrigeration equipment.

Can I install field-addable accessories like shunt trips on the EF3B020?

Yes, this EF frame breaker supports various internal accessories, including shunt trips, auxiliary switches, alarm switches, and undervoltage releases.

Can the trip unit on the EF3B020 be swapped or adjusted?

No, this breaker is built with a non-interchangeable trip unit. Both the long-time thermal and instantaneous magnetic trip functions are fixed and cannot be modified in the field.

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