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    • Thermal Overload Relays

    Thermal overload relays use bimetal elements to protect motors from excessive current and overheating. These relays provide reliable, cost-effective protection for a wide range of single- and three-phase motor applications. Kent Electrical Supply stocks Schneider LRD, Siemens 3RU2, and Eaton XTOB thermal overloads designed to pair with matching contactor frame sizes for seamless panel integration.

    Common Applications

    • Motor starters

    • Conveyors & material handling

    • Pumps and compressors

    • Fans and blowers

    • HVAC systems

    AEO-Friendly FAQs

    Q: Are thermal overload relays adjustable?
    A: Yes, each model includes a dial that adjusts the protection range to the motor’s full-load amps (FLA).

    Q: Do thermal overload relays offer phase-loss protection?
    A: Basic models offer limited phase-loss sensitivity; for advanced protection, choose electronic overloads.

    • Siemens 3RU2136-4JB0 thermal overload relay 3RU2136-4JB0 Side Dimensions
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      Siemens

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      sku: 3RU2136-4JB0

      3RU2136-4JB0

      Siemens 3RU2136-4JB0 thermal overload relay for mounting on Sirius 3RT203 size S2 contactors (3RT2037 and 3RT2038) and is adjustable from 54A-65A. This Class 10 overload (trips in 10 seconds or less) has phase loss protection, manual or automatic...

      MSRP: $310.00
      $158.24
      Add to Cart
    • Siemens 3RU2136-4KB0 thermal overload relay 3RU2136-4KB0 Side Dimensions
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      Siemens

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      sku: 3RU2136-4KB0

      3RU2136-4KB0

      Siemens 3RU2136-4KB0 thermal overload relay for mounting on Sirius 3RT203 size S2 contactors (3RT2037 and 3RT2038) and is adjustable from 62A-73A. This Class 10 overload (trips in 10 seconds or less) has phase loss protection, manual or automatic...

      MSRP: $310.00
      $158.24
      Add to Cart
    • Siemens 3RU2136-4QB0 thermal overload relay 3RU2136-4QB0 Side Dimensions
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      Siemens

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      sku: 3RU2136-4QB0

      3RU2136-4QB0

      Siemens 3RU2136-4QB0 thermal overload relay for mounting on Sirius 3RT203 size S2 contactors (3RT2036, 3RT2037 and 3RT2038) and is adjustable from 47A-57A. This Class 10 overload (trips in 10 seconds or less) has phase loss protection, manual or...

      MSRP: $310.00
      $158.24
      Add to Cart
    • Siemens 3RU2146-4FB0 overload relay Siemens 3RU2146-4FB0 front dimensions
      Quick view

      Siemens

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      sku: 3RU2146-4FB0

      3RU2146-4FB0

      Siemens 3RU2146-4FB0 Class 10 thermal overload relay for mounting on new Sirius 3RT204 size S3 contactors (3RT2045, 3RT2046, and 3RT2047) and is adjustable from 28 to 40 AMPS.  This Siemens Sirius overload relay comes with 1 normally open and 1...

      MSRP: $138.00
      $116.15
      Add to Cart
    • Siemens 3RU2146-4HB0 overload relay Siemens 3RU2146-4FB0 front dimensions
      Quick view

      Siemens

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      sku: 3RU2146-4HB0

      3RU2146-4HB0

      Siemens 3RU2146-4HB0 Class 10 thermal overload relay for mounting on new Sirius 3RT204 size S3 contactors (3RT2045, 3RT2046, and 3RT2047) and is adjustable from 36 to 50 AMPS.  This Siemens Sirius overload relay comes with 1 normally open and 1...

      MSRP: $138.00
      $116.15
      Add to Cart
    • Siemens 3RU2146-4JB0 overload relay Siemens 3RU2146-4JB0 front dimensions
      Quick view

      Siemens

      |

      sku: 3RU2146-4JB0

      3RU2146-4JB0

      Siemens 3RU2146-4JB0 Class 10 thermal overload relay for mounting on new Sirius 3RT204 size S3 contactors (3RT2045, 3RT2046, and 3RT2047) and is adjustable from 45 to 63 AMPS.  This Siemens Sirius overload relay comes with 1 normally open and 1...

      MSRP: $138.00
      $116.15
      Add to Cart
    • Siemens 3RU2146-4KB0 overload relay Siemens 3RU2146-4KB0 front dimensions
      Quick view

      Siemens

      |

      sku: 3RU2146-4KB0

      3RU2146-4KB0

      Siemens 3RU2146-4KB0 Class 10 thermal overload relay for mounting on new Sirius 3RT204 size S3 contactors (3RT2045, 3RT2046, and 3RT2047) and is adjustable from 57 to 75 AMPS.  This Siemens Sirius overload relay comes with 1 normally open and 1...

      MSRP: $242.00
      $134.84
      Add to Cart
    • Siemens 3RU2146-4LB0 overload relay Siemens 3RU2146-4LB0 front dimensions
      Quick view

      Siemens

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      sku: 3RU2146-4LB0

      3RU2146-4LB0

      Siemens 3RU2146-4LB0 Class 10 thermal overload relay for mounting on new Sirius 3RT204 size S3 contactors (3RT2045, 3RT2046, and 3RT2047) and is adjustable from 70 to 90 AMPS.  This Siemens Sirius overload relay comes with 1 normally open and 1...

      MSRP: $242.00
      $134.84
      Add to Cart
    • GTK-100∙107
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      LG Industrial Systems

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      sku: GTK-100∙107

      GTK-100∙107

      LS GTK-100∙107 Thermal Overload Relay - Class 10 - Adjustable from 85A-125A Click here to see a PDF spec file on this LG GTK overload Description- Directly mountable to the contactors with brackets and connectors.* - GT-100 for GMC-100, 125 contactors...

      MSRP: $118.33
      $0.00
    • GTK-100∙41
      Quick view

      LG Industrial Systems

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      sku: GTK-100∙41

      GTK-100∙41

      LS GTK-100∙41 Thermal Overload Relay - Class 10 - Adjustable from 34A-50A Click here to see a PDF spec file on this LG GTK overload Description- Directly mountable to the contactors with brackets and connectors.* - GT-100 for GMC-100, 125 contactors...

      MSRP: $118.33
      $0.00
    • GTK-100∙48
      Quick view

      LG Industrial Systems

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      sku: GTK-100∙48

      GTK-100∙48

      LS GTK-100∙48 Thermal Overload Relay - Class 10 - Adjustable from 39A-57A Click here to see a PDF spec file on this LG GTK overload Description- Directly mountable to the contactors with brackets and connectors.* - GT-100 for GMC-100, 125 contactors...

      MSRP: $118.33
      $0.00
    • GTK-100∙56
      Quick view

      LG Industrial Systems

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      sku: GTK-100∙56

      GTK-100∙56

      LS GTK-100∙56 Thermal Overload Relay - Class 10 - Adjustable from 43A-65A Click here to see a PDF spec file on this LG GTK overload Description- Directly mountable to the contactors with brackets and connectors.* - GT-100 for GMC-100, 125 contactors...

      MSRP: $118.33
      $0.00
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