Eaton
Eaton FH51 Thermal Unit Trip Class 20
Thermal overload unit rated Trip Class 20 for 24 to 30.3 A full-load current, compatible with NEMA Size 1 and 2 starters
- TypeIndustrial Electrical Controls & Automation
- ColorTransparent
- Trip Class 20 provides reliable overload protection
- Full-load current range 24 to 26.2 A suits motor circuits
- Extended range 27.7 to 30.3 A covers higher loads
- Compatible with NEMA Size 1 and 2 starters
- Fits Series A200 and B100 controllers
Eaton FH51 Thermal Unit
The Eaton FH51 thermal unit provides Trip Class 20 overload protection for motor starters. It is designed for electricians and maintenance technicians who need reliable thermal safeguarding in industrial control panels.
Compatible with NEMA Size 1 and 2 starters
This unit fits Series A200 and B100 motor starters across multiple current ranges. It replaces heater elements in existing overload relays, freeing panel space by using the starter's built-in mechanism instead of a separate breaker.
Sustained overload response
Under continuous overcurrent the thermal element heats gradually, tripping at the calibrated 20-class curve rather than instantly. This behaviour suits motors that experience routine start-up surges but must be disconnected during prolonged overload conditions.
Highlights
- Trip Class 20 provides reliable overload protection
- Full-load current range 24 to 26.2 A suits motor circuits
- Extended range 27.7 to 30.3 A covers higher loads
- Compatible with NEMA Size 1 and 2 starters
- Fits Series A200 and B100 controllers
Specifications
| Brand | Eaton |
|---|---|
| Type | Industrial Electrical Controls & Automation |
| Color | Transparent |
Questions about this item
At what full-load current does the FH51 thermal unit trip under sustained overload?
The unit trips between 24 and 26.2 A or between 27.7 and 30.3 A depending on the selected heater range.
How much heat does the FH51 generate during continuous operation?
As a passive thermal overload relay it produces only the heat from its own current path; no active cooling or fan noise is present.
Which starter or contactor series must I already have for the FH51 to fit?
It is compatible with Eaton Series A200 and B100 starters in NEMA sizes 1 and 2.
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