Tesla | Thermal Overload Relay 1.6-2.5A Adjustable | Manual or Automatic Reset
The Tesla D1307 is a thermal overload relay with a trip current adjustable from 1.6 to 2.5A, sized for small motor circuits. The D1307 mounts directly to the matching Tesla contactor frame sizes and opens its contact when current stays above the dial setting long enough to heat the motor. Tesla lists the relay with manual and automatic reset options.
Small motors are the ones most often left unprotected. A 1.6 to 2.5A load sits considerably below the rating of the protective device feeding the switchboard, so that device never registers a stalled damper or a seized extraction fan. The winding simply overheats. A thermal overload relay in this band monitors the current the motor actually draws rather than the capacity of the circuit. Calibrating the dial against the nameplate figure gives a small motor protection scaled to its own thermal limitations.
Fractional kilowatt motors appear throughout commercial plant: dampers, actuators, extraction units, dosing pumps, and circulation sets. The D1307 covers the 1.6 to 2.5A adjustment band, which accommodates the majority of those installations. Because Tesla lists manual and automatic reset options, one part number services an attended plant room and an unattended rooftop unit. Fitting the correct band during construction avoids a nuisance-tripping callout on commissioning day.
Features
- 1.6 to 2.5A adjustment range — the dial sets trip current anywhere between 1.6 and 2.5A to match a small motor nameplate.
- Small motor coverage — the band suits fractional kilowatt loads sitting well under the rating of the upstream protective device.
- Sustained overcurrent response — the D1307 acts on prolonged overload rather than on momentary current peaks.
- Start-up inrush tolerance — the thermal element rides through starting inrush and responds to load that stays elevated.
- Manual or automatic reset — Tesla lists both modes, so one part number covers attended and unattended equipment.
- Direct contactor mounting — the D1307 fits the matching Tesla contactor frame sizes without a separate mounting kit.
- Front-mounted current dial — the setting adjusts from the face of the relay once it is fitted to the contactor.
- Set to nameplate, not breaker rating — on a load this small the breaker sits far above the motor, so only the D1307 dial setting delivers real protection.
- Not short-circuit protection — a thermal overload relay acts on sustained overload, so the circuit still needs separate fault protection upstream.
- No trip class published — the Tesla datasheet gives the adjustment range and contactor fit but publishes no trip class or voltage rating.
- Licensed installation required — the D1307 forms part of a motor control circuit, and Sparky Direct supplies it for installation by a licensed electrician.
- One year warranty — a one year warranty applies for domestic and commercial use, handled as a return to Sparky Direct.
Where to use
- Damper and actuator motors — the D1307 protects small drive motors on air handling dampers and valve actuators.
- Small extraction fans — covers roof and inline extraction units whose motors draw within the 1.6 to 2.5A band.
- Dosing and circulation pumps — protects low current pump motors running chemical dosing and circulation duty.
- Feeder and short conveyor drives — small drive motors where a jam raises running current without producing a fault.
- Commercial refrigeration — condenser and evaporator fan motors sitting in the low current band on refrigeration plant.
- Workshop and laboratory equipment — small fixed machines and extraction rigs run from a contactor starter.
- Starter builds and repairs — the D1307 fits a new starter build or replaces a band that no longer suits the motor.
A thermal overload relay is not short-circuit protection. The D1307 acts on sustained overcurrent, so the motor circuit still needs a separate device for fault current. A motor drawing outside 1.6 to 2.5A at full load is not covered by this relay, and winding the dial to the top of the band to stop nuisance tripping leaves that motor unprotected. Tesla publishes no trip class or voltage rating, so confirm both against the starter and the supply.
