B11.5 SQUARE D Overload Relay Thermal Unit Fnob

Review SQUARE D Squareb11.5 Overload Relay Thermal Unit Fnob

The Square B11.5 Overload Relay Thermal Unit FNOB is a versatile electrical component designed to provide overload protection and thermal overload protection for various electrical applications. This unit is suitable for use with single-phase AC circuits and comes in a compact, square design, making it an ideal choice for space-constrained installations.

The B11.5 Overload Relay Thermal Unit FNOB features a thermal overload protection function that activates when the temperature of the protected circuit exceeds a safe level. This function helps prevent damage to the electrical components and ensures the safety of the users. The thermal element is designed to reset automatically once the temperature returns to normal, allowing the circuit to resume operation.

This unit also includes an overload protection function that disconnects the circuit when the current flowing through it exceeds the safe limit. This function helps prevent electrical overloads that could cause damage to the circuit or pose a safety hazard. The overload element is thermally resettable, meaning it will reset automatically once the overload condition has been rectified.

The Square B11.5 Overload Relay Thermal Unit FNOB has a rating of 15 amps at 125 volts and comes with a transparent, hinged cover that allows for easy access to the thermal element for inspection and maintenance. The unit is also designed with a removable terminal block that allows for easy wiring and connection of the electrical components.

The thermal unit is suitable for use in various applications, including HVAC systems, water heaters, and other electrical appliances. It is designed to meet UL and CSA standards for safety and reliability, ensuring peace of mind for users. The unit is also RoHS compliant, meaning it is free of certain hazardous materials, making it an environmentally friendly choice.

In summary, the Square B11.5 Overload Relay Thermal Unit FNOB is a compact and versatile electrical component that provides both overload and thermal overload protection for single-phase AC circuits. It is suitable for use in various applications and is designed to meet the highest safety and reliability standards. Its transparent cover and removable terminal block make it easy to install and maintain, making it a popular choice among electrical professionals and DIY enthusiasts.

The Square D B11.5 Overload Relay Thermal Unit FNOB is an essential electrical component used to protect motors and other electrical loads from overloading and overheating. Let's discuss some pros and cons of buying this particular model to help you make an informed decision.

1. Overload Protection: The B11.5 Overload Relay provides overload protection for your electrical loads. It automatically disconnects the circuit when the current exceeds the rated value, preventing damage to the motor and other components.

2. Thermal Protection: In addition to overload protection, this unit also provides thermal protection. It disconnects the circuit when the temperature exceeds a certain threshold, preventing damage due to overheating.

3. FNOB Design: The Fused No Voltage (FNOB) design of this unit provides additional protection against short circuits by incorporating a fuse into the unit.

4. Easy Installation: The unit is easy to install and requires minimal wiring. It can be mounted in a NEMA 1, 3R, 4, 4X, 6, 12, or 13 enclosure.

5. Cost-Effective: Compared to other overload and thermal protection devices, the B11.5 Overload Relay is reasonably priced, making it a cost-effective solution for protecting your electrical loads.

1. Limited Capacity: The B11.5 Overload Relay has a limited capacity, with a maximum current rating of 50 amps and a maximum voltage rating of 277 volts. If you have electrical loads with higher current or voltage requirements, you may need to consider a different model.

2. Manual Reset: The unit requires manual reset after a trip, which can be inconvenient in some applications. Automatic reset units may be a better option for applications where frequent resetting is required.

3. Limited Temperature Range: The B11.5 Overload Relay has a limited temperature range, with a minimum temperature rating of 32 F and a maximum temperature rating of 104 F. If you operate in extreme temperatures, you may need to consider a different model.

The Square D B11.5 Overload Relay Thermal Unit FNOB is a cost-effective and reliable solution for providing overload and thermal protection for electrical loads with a maximum current rating of 50 amps and a maximum voltage rating of 277 volts. Its easy installation and FNOB design provide additional protection against short circuits. However, its limited capacity, manual reset, and temperature range may be a concern for some applications.

If you have electrical loads with a current and voltage requirement within the B11.5 Overload Relay's capacity, and you don't require automatic reset or operation in extreme temperatures, this unit is a good choice for your application. However, if you have higher current or voltage requirements, or you need automatic reset or operation in extreme temperatures, you may need to consider a different model with a higher capacity and the desired features.

Details:

Most items are in stock when they listed. The item has its original packaging but it is not sealed. Squareb11.5 overload relay thermal unit, melting alloy, class 20. Squareb11.5 overload relay thermal unit manufactured by Square.

Special instructions. The product must be the original item shipped, with matching serial numbers if applicable. Manufacturer part number: B11.5. A new, unused item with no signs of wear.

2-year MRI shield protection plan included.

specifications genpurrelays:

• brand: Square D
• mpn: B11.5
• part type: Unit

payments genpurrelays:

• credit card: mastercard
• wallet: google-pay
• other

shipping genpurrelays:

• type: calculated
• service: ups ground, ups next day air
• transit: 5-8 days
• carrier: ups
• class: standard, one-day

offer genpurrelays:

• prices: $14.00–$99.99
• item condition:
  • New – Open box
  • New
  • Seller refurbished
  • Used
• in stock #: 5
• best offers: true
• sold #: 8
• options: ship-to-home
• availability: in stock
• started: january 22, 2026

returns genpurrelays:

• method: money back
• policy: returns accepted
• paid by: buyer
• time: 30 days

seller genpurrelays:

• # reviews: 2005 7
• city: mount sterling, kentucky
• rating: 99.6%

general genpurrelays:

• category: Business & Industrial > Electrical Equipment Supplies > General Purpose Relays