Product Description:
The KSD301 Snap Disc Thermoswitch, 10A 250V Normally Closed(NC) | Bimetal Thermal Switch for Kettle, Microwave & Floor Scrubber from Qimao Electronic uses a bimetallic disc as both sensor and switch. Contacts are normally closed at room temperature, so the load stays powered until the disc senses the preset action temperature and snaps open. Once the surface cools, the disc snaps back and the contact closes again. Rated 10A at 250VAC, with AC2500V electrical strength and no breakdown or flashover. Action temperature is set at 5°C per step, from 40–150°C in phenolic housing or 40–260°C in ceramic. Terminal options include flat foot and bent foot. Mounting styles cover fixed ring and movable ring. It works as a standalone thermal cutoff—no coil, no spring, no control board.
Specification:
| Item | Typical |
|---|---|
| Product Name: | KSD301 Snap Disc Thermoswitch, 10A 250V Normally Closed(NC) | Bimetal Thermal Switch for Kettle, Microwave & Floor ScrubberKSD301 Snap Disc Thermoswitch, 10A 250V Normally Closed(NC) | Bimetal Thermal Switch for Kettle, Microwave & Floor Scrubber |
| Model: | KSD301-07 |
| Electrical Rating | 10A / 16A at 250VAC |
| Contact Rating: | 250VAC 10A / 125VAC 15A (customizable) |
| Action Temperature Range: | Bakelite type: 40~150℃, adjustable in 5℃ increments;Ceramic type: 40~260℃, adjustable in 5℃ increments |
| Action Tolerance: | Optional ±3℃ / ±5℃ / ±10℃ |
| Set Point Tolerance: | ±3°C to ±5°C (depending on model) |
| Contact Type: | Normally Closed (NC, auto-open at target temp); Normally Open (NO) customizable |
| Typical Applications | Pressure cookers, water dispensers, microwave ovens, electric water heaters, electric kettles and other heating appliances |
| Dielectric Strength: | AC 2500V for 1 minute, no breakdown or flashover |
| Mounting: | Bent foot, fixed ring / movable ring |
Working Principle:
The KSD301 Snap Disc Thermoswitch, 10A 250V Normally Closed(NC) | Bimetal Thermal Switch for Kettle, Microwave & Floor Scrubber uses a bimetallic disc as both sensor and switch. At room temperature the disc stays convex, holding the normally closed contact together. When the mounting surface reaches the preset action temperature, the disc snaps to concave and pushes the contact open, cutting power to the load. As the surface cools, the disc snaps back at the reset temperature and the contact closes again. There is no coil, no spring, and no external sensor—the disc does everything. Response is fast and repeatable, and the trip point does not drift with age. This is why the KSD301 is widely used as a standalone thermal cutoff in appliances.
Features:
-
KSD301 Snap Disc Thermoswitch, 10A 250V Normally Closed(NC) | Bimetal Thermal Switch for Kettle, Microwave & Floor Scrubber
Closed at room temperature, opens when the disc reaches the preset limit. Fail-safe for overheat protection. -
10A / 16A at 250VAC
Covers kettles, microwaves, floor scrubbers and similar loads. Inductive loads need derating or arc suppression. -
Action temperature 40–260°C, 5°C per step
Phenolic covers 40–150°C; ceramic extends to 260°C. Tight steps let you match the trip point to your design limit. -
±3°C / ±5°C accuracy
Phenolic holds ±3°C; ceramic holds ±5°C. Less safety margin needed in your design. -
Flat foot or bent foot terminals
Flat for straight wiring, bent for side-entry. Both accept standard quick-connects or solder. -
Fixed ring or movable ring mounting
Fixed ring for repeatable thermal contact; movable ring for more installation freedom. -
AC2500V electrical strength
No breakdown or flashover. Matters near control electronics or high-voltage parts. -
Automatic reset
Re-closes after the surface cools below the reset point. No manual reset button. -
Snap action, minimal arcing
Fast opening reduces arc duration and RF interference. Suitable near control electronics. -
No coil, no spring, no sensor
The disc is the whole mechanism. Fewer parts, fewer failure modes, no drift with age.
Application Scenarios:
-
KSD301 Snap Disc Thermoswitch, 10A 250V Normally Closed(NC) | Bimetal Thermal Switch for Kettle, Microwave & Floor Scrubber used for electric kettles
Boil-dry cutoff on the heating plate. Auto-reset version re-closes after the plate cools. -
Microwave ovens
Thermal cutoff on the magnetron, transformer, or cavity wall. Opens before these components overheat. -
Floor scrubbers
Protects the drive motor and pump motor from overheating under sustained load or blocked airflow. -
Water dispensers
Dry-boil protection on the heating plate. Auto-reset version re-closes after cooling. -
Pressure cookers
Overheat limit on the main heating element. Opens if the primary control fails. -
Electric water heaters
High-limit protection on the heating element. Opens if water temperature climbs past the set limit. -
Motors and transformers
Limits winding temperature under overload or blocked ventilation. -
Power tools
Thermal protection under sustained load or blocked cooling vents. Compact body fits inside the tool housing.
Customization Service:
