SQF Thermal Fuse Cement Resistors Features: 1. It is suitable for protecting circuit boards. 2. Flameproof construction in a ceramic case, resistant to humidity and insulation. 3. In high resistance value, the winding cores will be replaced by power film cores. 4. Excellent anti-surge characteristics and accurate fusibility.
SQF Thermal Fuse Cement Resistors
Products | SQF Thermal Fuse Cement Resistors |
Features | 1. It is suitable for protecting circuit boards. 2. Flameproof construction in a ceramic case, resistant to humidity and insulation. 3. In high resistance value, the winding cores will be replaced by power film cores. 4. Excellent anti-surge characteristics and accurate fusibility. |
Electrical And Mechanical Performance of SQF Thermal Fuse Cement Resistors:
Characteristics | Standards | Test Methods |
Resistance Tolerance | ±5%(J) | - |
Resistance Temp. Coeff. | ±300 ppm/°C; <1Ω:±600ppm/°C | - |
Power Rating Load | Surface temp.130°C Max.ΔR/R≤±1% | Rated voltage for 30 minutes |
Short Time Overioad | ±2% | 10 times of rated wattage for 5 seconds.
|
Dielectric Withstanding Voltage | No evidence of mechanical damage or insulation breakdown.
| AC 1000V for 1 minutes.
|
Insulation Resistance | 10,00MΩ | DC 500V megger
|
Terminal Strength
| No evidence of mechanical damage.
| 4.5 kg
|
Solder-ability | Minimum95%coverage | 235 ± 5°C for 2 seconds |
Resistance to Soldering Heat | No evidence of mechanical damage.ΔR/R≤±1% | 265±5°C for 10 ±1 seconds
|
Environmental Characteristics of SQF Thermal Fuse Cement Resistors:
Characteristics | Standards | Test Methods |
Temp. Cycle | △R/R≤±1% | -25°C ( 1 hrs.)—► Room Temp.( 2 hrs.) —►+Operating temp.( 1 hrs.) —►Room Temp.( 2 hrs.) / ( 5 cycles) |
Load Life | △R/R≤±5% | Rated power load 90 minutes ON 30 minutes OFF 70°C 1000 hours |
Moisture-proof Load Life | △R/R≤±5% | Rated power load 90 minutes ON 30 minutes OFF 40°C95%RH500 hours |
Nonflammability
| not flamed
| 16 times of rated wattage for 5 min.
|
Dimensions of SQF Thermal Fuse Cement Resistors:
Rated Wattage | W±1 | S±1 | H±1.5 | P+2/-1 | d1 ±0.1 | d2±0.1 | Resistance Range (Ω) |
SQF3 | 12 | 8 | 25 | 5 | 0.8 | 2A:0.6 3A:0.6 5A:1.0 10A:1.0 | 0.1~50K |
SQF5 | 13 | 9 | 25 | 5 | 0.8 | 0.1~50K | |
SQF7 | 13 | 9 | 39 | 5 | 0.8 | 0.1~50K | |
SQF10S | 16 | 12 | 35 | 7.5 | 0.8 | 0.1~50K | |
SQF10 | 20Max. | 9 | 25Max. | 12.5 | 0.8 | 0.8 | 0.1-50K |
Ratings of SQF Thermal Fuse Cement Resistors:
Rated Current | Rated Functioning Temperature | Rated Wattage | ||||
SQF3 | SQF5 | SQF7 | SQF10 | SQF10S | ||
3A | 145°C | 1.6W | 1.6W | 2.2W | 3.2W | 2.5W |
5A | 145°C | 1.6W | 1.6W | 2.2W | 3.2W | 2.5W |
10A | 132°C | 1.6W | 1.6W | 2.2W | 3.2W | 2.5W |
10A | 185°C | 2.1W | 2.1W | 2.4W | 4.2W | 3.5W |
Derating Curve of SQF Thermal Fuse Cement Resistors:
For resistors operated in ambient temperatures above 25°C , power rating must be derated in accordance with the curve below.