1. H20,H21 series thermostat’s Principle and structure
H20,H21serial universal and enhanced protectors with large metal casing are composed of the thermal conductive metal casing, bimetallic parts welded with silver alloy contact point, conductive bracket, insulation fixation stand, fixed contact strip and heat resistance cable. In case of abnormal operation, along with the increase of the environment temperature to the set value, the bimetallic parts perform quick action, open the contact point, and disconnect the circuit. When the device is cooled to the temperature for safe operation, the contact point will automatically closes and recover normal operation.
2. H20,H21series thermal protector’s Specification
2.1.Switch type: normally closed, normally opened.
2.2.Operating Voltage / Current: AC250V / 5A; AC125V / 8A
2.3.Operating Temperature: 40~150℃ (one step for every 5°C)
2.4.Standard Tolerance: ±3°C / ±5°C / ±7°C
2.5.Reset temperature: operating temperature decrease by 15-45°C
2.6.Contact Closure resistance: ≤50mΩ
2.7.Insulation resistance: ≥100mΩ
2.8.Electric strength: AC1500V/1min free from phenomena of break down and flashover.
2.9.Service life: 10000 times
| Electrical Rating | DC-12V max 12A; DC-24V max 10A; AC-125V max 8A; AC-250V max 16A |
| Open temperature | (30~150)±5°C; 5°C a step |
| Reset temperature | 2/3 of the action temperature with tolerance of ±15°C. Reset temperature can also be provided according to customers' requirement. |
| Life times | 10000 times |
| Contact Closure resistance: | ≤50mΩ |
| Insulation resistance: | ≥100mΩ |
| Electric strength: | 2.10. AC1500V/1min free from phenomena of break down and flashover. |
| UL File no | E487478 |
| CQC certificate no | CQC16002142880 |
| TUV certificate no | B160592241002 |
3. H20,H21series thermal protector’s Dimension
| Model | Case | Length(mm) | width(mm) | High(mm) | Vol.&Current | Lead wire |
| H20 | Plastic | 18.5 | 8 | 4 | DC-12V max 12A; DC-24V max 10A; AC-125V max 8A; AC-250V max 10A | #20 3135, end 5mm half tripping, length is 70mm, or according to customer’s require |
| H21 | Metal | 18.5 | 7.3 | 3.8 |
| H21 | Metal | 20 | 8 | 4 | AC250V 20A | #16 3135 |
| BH-A1D | Metal | 15 | 6.6 | 3.2 | DC-12V max 12A; DC-24V max 10A; AC-125V max 8A; AC-250V | #20 3135, #22 3266,#22 3135, end 5mm half tripping, length is 70mm, or according to customer’s require |
| BH-B2D | Plastic | 15 | 7.1 | 3.8 |
| BH-TB02B-B8D | Plastic | 15 | 5.2 | 2.4 | DC-12V max 4A; DC-24V max 3A; AC-125V max 3A; AC-250V max 2A | 3266-AWG24#, 3135-AWG24# or nickel strip normally, length is 70 mm or according to customer’s require |
4. H20,H21series temperature protector’s Application
H20,H21series is applicable to chargeable battery, ballast, massager, micro motor, transformer, electric tools, heat electric appliance and instrument etc.
The product UL,CQC,TUV and RoHS certification approval.
