Bimetallic Thermostat and Thermal Protector with Normally Closed or Normally Open Contacts Auto Reset or Manual Reset Sealed Firmly for Reliable Over-Current and Over-Temperature Protection
The BW & BH series thermostats provide reliable protection against over-current and over-temperature conditions. These sealed units feature small internal resistance, operate silently, and reset automatically. The bimetallic components respond to both temperature and current changes, altering their state to either cut off or complete the circuit as needed for protection.
The BH series offers enhanced safety compared to standard protectors, with immediate response to sudden current surges without temperature lag.
| 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. Custom reset temperatures available |
| Life times | 10000 cycles |
| Size | L15mm W7.1mm H3.8mm |
| Lead wire | #22 3266, end half tripping, length is 70mm (customizable) |
| Certifications | UL File no: E487478 CQC certificate no: CQC16002142880 TUV certificate no: B160592241002 |
| Model | Case | Length(mm) | Width(mm) | Height(mm) | Voltage & 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 (customizable) |
| H21 | Metal | 18.5 | 7.3 | 3.8 | 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 (customizable) |
| 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 (customizable) |
| Code | Temperature | Code | Temperature |
|---|---|---|---|
| 30 | 30℃ | 100 | 100℃ |
| 35 | 35℃ | 105 | 105℃ |
| 40 | 40℃ | 110 | 110℃ |
| 45 | 45℃ | 115 | 115℃ |
| 50 | 50℃ | 120 | 120℃ |
| 55 | 55℃ | 125 | 125℃ |
| 60 | 60℃ | 130 | 130℃ |
| 70 | 70℃ | 135 | 135℃ |
| 75 | 75℃ | 140 | 140℃ |
| 80 | 80℃ | 145 | 145℃ |
| 85 | 85℃ | 150 | 150℃ |
| 90 | 90℃ |
BH series thermal protectors are effective security devices used in:
- 1.5 horsepower motors
- Lighting devices
- Inverter welding machines
- Switch power supplies
- Rechargeable battery packs
- Fluorescent lamp ballasts
- Portable power tools
- Various electric appliances
Enforced types (3.5MPa pressure rating) are suitable for plastic-coated motor installations.
These universal protectors feature large metal casings containing bimetallic components with silver alloy contacts, conductive brackets, and insulation stands. During abnormal operation, rising temperatures cause the bimetallic components to quickly open the circuit, automatically resetting when temperatures return to safe levels.
| 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 |
| Life times | 10000 cycles |
| Contact Closure resistance | ≤50mΩ |
| Insulation resistance | ≥100mΩ |
| Electric strength | AC1500V/1min (no breakdown or flashover) |
All products have UL, CQC, TUV and RoHS certification approval.
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