Wirewound Resistors
Crohm Series CW wirewound resistors serve light-to-medium-duty braking of variable-frequency drives, speed regulation, wye-delta starting, heating, elevator controls, high-resistance neutral grounding and any type of AC or DC power circuit. Resistance values range from 0.2 to 300 ohms with current capabilities between 35 and 1 amp.
Design
- High-quality stainless resistor alloy wound into a spring
- Wrapped onto a spirally grooved ceramic insulating core
- Stainless-steel terminals clamped to the core at each end
- Open design allowing direct ambient-air cooling
- Cordierite core with excellent thermal-shock resistance and mechanical strength
- 3/8" center hole for 1/4"–5/16" threaded rod
Specifications
| Voltage insulation | 1000 volts |
| Insulation resistance (dry) | 1000 MΩ minimum |
| Resistance tolerance | ± 10% standard |
| Coefficient of resistivity | ~5% increase at full operating temperature |
| Operating temperature | 375 °C rise above ambient |
| Ambient derating | 40 °C base; −10% @ 50 °C, −20% @ 80 °C, −30% @ 100 °C |
Ordering & part numbers
Naming convention: CW(resistance × 100). Example: CW1000 = a 10 ohm, 384 watt resistor. 30 standard part numbers range from CW20 (0.20 Ω, 250 W) through CW30000 (300 Ω, 243 W).
Standard ratings
Representative standard part numbers. Non-standard resistance, wattage and current values are available — request a quote.
| Part No. | Resistance (Ω) | Power (W) | Max Current (A) |
|---|---|---|---|
| CW20 | 0.20 | 250 | 35.4 |
| CW40 | 0.40 | 260 | 25.5 |
| CW60 | 0.60 | 270 | 21.2 |
| CW80 | 0.80 | 280 | 18.7 |
| CW100 | 1.0 | 290 | 17.0 |
| CW150 | 1.5 | 300 | 14.1 |
| CW200 | 2.0 | 310 | 12.4 |
| CW300 | 3.0 | 320 | 10.3 |
| CW400 | 4.0 | 330 | 9.1 |
| CW500 | 5.0 | 340 | 8.2 |
| CW700 | 7.0 | 350 | 7.1 |
| CW1000 | 10 | 384 | 6.2 |
| CW1500 | 15 | 380 | 5.0 |
| CW2000 | 20 | 375 | 4.3 |
| CW3000 | 30 | 370 | 3.5 |
| CW4000 | 40 | 360 | 3.0 |
| CW5000 | 50 | 355 | 2.7 |
| CW7000 | 70 | 345 | 2.2 |
| CW10000 | 100 | 330 | 1.8 |
| CW12000 | 120 | 320 | 1.6 |
| CW15000 | 150 | 310 | 1.4 |
| CW18000 | 180 | 300 | 1.3 |
| CW20000 | 200 | 290 | 1.2 |
| CW22000 | 220 | 280 | 1.1 |
| CW25000 | 250 | 265 | 1.0 |
| CW27000 | 270 | 255 | 1.0 |
| CW28000 | 280 | 250 | 0.9 |
| CW29000 | 290 | 247 | 0.9 |
| CW29500 | 295 | 245 | 0.9 |
| CW30000 | 300 | 243 | 0.9 |
Related products
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