CWT Ultra-mini Rogowski Coil
- Brand
- PEM
- Origin
- United Kingdom

A compact coil senses current in the conductor under test. Select by peak current, sensitivity and bandwidth.
Key specification options
- Sensitivity (mV/A)
- 200 / 100 / 50 and more
- Peak (A)
- 30 / 60 / 120 and more
- Noise (mVp-p)
- 20 / 15 / 10 and more
- Droop (%/ms)
- 80 / 65 / 35 and more
- LF(-3dB) bandwidth (Hz)
- 116 / 67 / 34 and more
- Peak di/dt (A/ns)
- 2.0 / 4.0 / 8.0 and more
Product design
CWT Ultra-mini is intended for smaller measurement locations, including evaluation of current probing arrangements near semiconductor leads. Selection should include the actual clearance for passing the coil and the space available after it is closed.
Measurement and application
Current waveform measurements depend on both probe placement and signal conditioning. Start with the conductor shape, available space and the waveform you need to observe, then consider the coil and measurement equipment together.
Selection and connections
Distinguish temporary testing from fixed installation, and confirm the required coil, integrator and cable combination rather than assuming that similar looking accessories are interchangeable.
Series models & specifications
CWT Standard Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak current (A) | Noise (mV p-p) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | di/dt(kA/μs) | High-frequency bandwidth (3dB), MHz · 300mm coil | High-frequency bandwidth (3dB), MHz · 700mm coil |
|---|---|---|---|---|---|---|---|---|
| CWT/3N | 10.0 | 600 | 14 | 0.9 | 1.0 | 2.0 | 10 | 5 |
| CWT/6 | 5.0 | 1.2k | 12 | 0.9 | 1.0 | 8.0 | 16 | 10 |
| CWT/15 | 2.0 | 3.0k | 7.0 | 0.7 | 0.8 | 20 | 16 | 10 |
| CWT/30 | 1.0 | 6.0k | 5.0 | 0.5 | 0.6 | 40 | 16 | 10 |
| CWT/60 | 0.5 | 12k | 3.0 | 0.35 | 0.4 | 40 | 16 | 10 |
| CWT/150 | 0.2 | 30k | 3.0 | 0.2 | 0.2 | 40 | 16 | 10 |
| CWT/300 | 0.1 | 60k | 3.0 | 0.1 | 0.1 | 40 | 16 | 10 |
CWT HF Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak current (A) | Noise (mV p-p) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | di/dt(kA/μs) | High-frequency bandwidth (3dB), MHz · 300mm coil | High-frequency bandwidth (3dB), MHz · 700mm coil |
|---|---|---|---|---|---|---|---|---|
| CWTHF/015 | 200 | 30 | 15 | 85 | 150 | 2.0 | 20 | 8 |
| CWTHF/03 | 100 | 60 | 11 | 78 | 105 | 4.0 | 20 | 8 |
| CWTHF/06 | 50 | 120 | 8.0 | 70 | 80 | 8.0 | 20 | 10 |
| CWTHF/1 | 20 | 300 | 6.0 | 50 | 50 | 20 | 20 | 10 |
| CWTHF/3 | 10 | 600 | 12 | 11 | 12 | 40 | 30 | 15 |
| CWTHF/6 | 5.0 | 1.2k | 12 | 5.5 | 6.0 | 80 | 30 | 15 |
| CWTHF/15 | 2.0 | 3.0k | 10 | 3.0 | 3.0 | 80 | 30 | 15 |
| CWTHF/30 | 1.0 | 6.0k | 10 | 1.5 | 1.5 | 120 | 30 | 15 |
| CWTHF/60 | 0.5 | 12k | 8.0 | 1.0 | 1.0 | 120 | 30 | 15 |
| CWTHF/150 | 0.2 | 30k | 5.0 | 0.8 | 0.8 | 120 | 30 | 15 |
| CWTHF/300 | 0.1 | 60k | 5.0 | 0.2 | 0.2 | 120 | 30 | 15 |
| CWTHF/600 | 0.05 | 120k | 5.0 | 0.06 | 0.05 | 120 | 30 | 15 |
| CWTHF/1500 | 0.02 | 300k | 5.0 | 0.035 | 0.03 | 120 | 30 | 15 |
CWT Mini Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak current (A) | Noise (mV p-p) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | di/dt(kA/μs) | High-frequency bandwidth (3dB), MHz · 100mm coil | High-frequency bandwidth (3dB), MHz · 200mm coil |
|---|---|---|---|---|---|---|---|---|
| CWTMini/03 | 100 | 60 | 15 | 6.6 | 7.0 | 1.0 | 10 | 5.0 |
| CWTMini/06 | 50 | 120 | 15 | 4.8 | 5.0 | 2.0 | 10 | 5.0 |
| CWTMini/1 | 20 | 300 | 12 | 3.6 | 4.0 | 2.5 | 20 | 15 |
| CWTMini/3 | 10 | 600 | 10 | 1.8 | 2.0 | 5.0 | 20 | 15 |
| CWTMini/6 | 5.0 | 1.2k | 10 | 0.8 | 0.9 | 10 | 20 | 15 |
| CWTMini/15 | 2.0 | 3.0k | 8.0 | 0.4 | 0.5 | 25 | 20 | 15 |
| CWTMini/30 | 1.0 | 6.0k | 7.0 | 0.25 | 0.3 | 40 | 20 | 15 |
| CWTMini/60 | 0.5 | 12k | 5.0 | 0.2 | 0.2 | 40 | 20 | 15 |
| CWTMini/150 | 0.2 | 30k | 5.0 | 0.1 | 0.1 | 40 | 20 | 15 |
| CWTMini/300 | 0.1 | 60k | 5.0 | 0.05 | 0.05 | 40 | 20 | 15 |
| CWTMini/600 | 0.05 | 120k | 5.0 | 0.03 | 0.02 | 40 | 20 | 15 |
| CWTMini/1500 | 0.02 | 300k | 5.0 | 0.03 | 0.02 | 40 | 20 | 15 |
CWT Ultra-mini Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak (A) | Noise (mVp-p) | Droop (%/ms) | LF(-3dB) bandwidth (Hz) | Peak di/dt (A/ns) | HF(-3dB) bandwidth (MHz) |
|---|---|---|---|---|---|---|---|
| CWTUM/015 | 200 | 30 | 20 | 80 | 116 | 2.0 | 30 |
| CWTUM/03 | 100 | 60 | 20 | 65 | 67 | 4.0 | 30 |
| CWTUM/06 | 50 | 120 | 15 | 35 | 34 | 8.0 | 30 |
| CWTUM/1 | 20 | 300 | 15 | 9.0 | 9.2 | 20 | 30 |
| CWTUM/3 | 10 | 600 | 10 | 6.0 | 6.2 | 40 | 30 |
| CWTUM/6 | 5.0 | 1200 | 10 | 3.0 | 3.2 | 70 | 30 |
| CWTUM/15 | 2.0 | 3000 | 5.0 | 2.0 | 2.0 | 70 | 30 |
| CWTUM/30 | 1.0 | 6000 | 5.0 | 2.0 | 2.0 | 70 | 30 |
CWT Mini 50HF Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak current (kA) | Noise (mVp-p) | Droop (%/ms) | LF(-3dB) bandwidth (Hz) | Peak di/dt (A/ns) | HF(-3dB) bandwidth (MHz), 100mm |
|---|---|---|---|---|---|---|---|
| CWTMini50HF/015 | 200 | 0.03 | 20 | 85 | 150 | 2.0 | 50 |
| CWTMini50HF/03 | 100 | 0.06 | 18 | 78 | 100 | 4.0 | 50 |
| CWTMini50HF/06 | 50 | 0.12 | 12 | 70 | 75 | 8.0 | 50 |
| CWTMini50HF/1 | 20 | 0.3 | 9.0 | 53 | 50 | 20 | 50 |
| CWTMini50HF/3 | 10 | 0.6 | 15 | 11 | 6.0 | 40 | 50 |
| CWTMini50HF/6 | 5.0 | 1.2 | 15 | 5.5 | 6.0 | 80 | 50 |
| CWTMini50HF/15 | 2.0 | 3.0 | 12 | 2.8 | 3.0 | 80 | 50 |
| CWTMini50HF/30 | 1.0 | 6.0 | 12 | 1.5 | 1.5 | 100 | 50 |
| CWTMini50HF/60 | 0.5 | 12.0 | 10 | 1.0 | 1.0 | 100 | 50 |
| CWTMini50HF/150 | 0.2 | 30.0 | 8.0 | 1.0 | 1.0 | 100 | 50 |
CWT UM-S Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak current (A) | Noise (mV p-p) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | di/dt(kA/μs) | High-frequency bandwidth (3dB), MHz |
|---|---|---|---|---|---|---|---|
| CWTUM-S/015 | 200 | 30 | 20 | 85 | 150 | 2.0 | 30 |
| CWTUM-S/03 | 100 | 60 | 18 | 78 | 100 | 4.0 | 30 |
| CWTUM-S/06 | 50 | 120 | 12 | 70 | 75 | 8.0 | 30 |
| CWTUM-S/1 | 20 | 300 | 10 | 53 | 50 | 20 | 30 |
| CWTUM-S/3 | 10 | 600 | 12 | 11 | 12 | 40 | 30 |
| CWTUM-S/6 | 5.0 | 1.2k | 12 | 5.5 | 6.0 | 80 | 30 |
| CWTUM-S/15 | 2.0 | 3.0k | 10 | 2.8 | 3.0 | 100 | 30 |
| CWTUM-S/30 | 1.0 | 6.0k | 10 | 1.5 | 1.5 | 100 | 30 |
| CWTUM-S/60 | 0.5 | 12.0k | 8.0 | 1.0 | 1.0 | 100 | 30 |
| CWTUM-S/150 | 0.2 | 30.0k | 5.0 | 1.0 | 1.0 | 100 | 30 |
CWT UM-F Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak current (A) | Noise (mV p-p) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | di/dt(kA/μs) | High-frequency bandwidth (3dB), MHz |
|---|---|---|---|---|---|---|---|
| CWTUM-F/03 | 100 | 60 | 20 | 85 | 150 | 4.0 | 20 |
| CWTUM-F/06 | 50 | 120 | 15 | 78 | 100 | 8.0 | 20 |
| CWTUM-F/1 | 20 | 300 | 15 | 53 | 50 | 20 | 20 |
| CWTUM-F/3 | 10 | 600 | 15 | 19 | 20 | 40 | 20 |
| CWTUM-F/6 | 5.0 | 1.2k | 15 | 9.3 | 10 | 80 | 20 |
| CWTUM-F/15 | 2.0 | 3.0k | 12 | 4.6 | 5.0 | 100 | 20 |
| CWTUM-F/30 | 1.0 | 6.0k | 12 | 2.4 | 2.6 | 100 | 20 |
| CWTUM-F/60 | 0.5 | 12.0k | 12 | 1.2 | 1.2 | 100 | 20 |
CWT UMHF-F Rogowski Coil
Model selection
| Model | Sensitivity (mV/A) | Peak current (A) | Noise (mV p-p) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | di/dt(kA/μs) | High-frequency bandwidth (3dB), MHz |
|---|---|---|---|---|---|---|---|
| CWTUMHF-F/03 | 100 | 60 | 20 | 85 | 150 | 4.0 | 30 |
| CWTUMHF-F/06 | 50 | 120 | 15 | 78 | 100 | 8.0 | 30 |
| CWTUMHF-F/1 | 20 | 300 | 15 | 53 | 50 | 20 | 30 |
| CWTUMHF-F/3 | 10 | 600 | 15 | 19 | 20 | 40 | 30 |
| CWTUMHF-F/6 | 5.0 | 1.2k | 15 | 9.3 | 10 | 80 | 30 |
| CWTUMHF-F/15 | 2.0 | 3.0k | 12 | 4.6 | 5.0 | 100 | 30 |
| CWTUMHF-F/30 | 1.0 | 6.0k | 12 | 2.4 | 2.6 | 100 | 30 |
| CWTUMHF-F/60 | 0.5 | 12.0k | 12 | 1.2 | 1.2 | 100 | 30 |
CWT LF Rogowski Coil
Standard Coils
| Model | Sensitivity (mV/A) | Peak current (kA) | di/dt(kA/μs) | Noise (mV pK-pK) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | Phase lead @50Hz (deg) | High-frequency bandwidth (3dB), MHz · 300mm coil | High-frequency bandwidth (3dB), MHz · 700mm coil |
|---|---|---|---|---|---|---|---|---|---|
| CWT03LF | 100.0 | 0.06 | 0.4 | 15.0 | 4.6 | 5.1 | 8.3 | 6.5 | 3.0 |
| CWT06LF | 50.0 | 0.12 | 0.8 | 15.0 | 2.3 | 2.6 | 4.2 | 6.5 | 3.0 |
| CWT1LF | 20.0 | 0.3 | 2.0 | 15.0 | 1.0 | 1.0 | 1.8 | 6.5 | 3.0 |
| CWT3LF | 10.0 | 0.6 | 4.0 | 15.0 | 0.5 | 0.55 | 0.85 | 6.5 | 3.0 |
| CWT6LF | 5.0 | 1.2 | 8.0 | 15.0 | 0.25 | 0.27 | 0.45 | 6.5 | 3.0 |
| CWT15LF | 2.0 | 3.0 | 11.0 | 15.0 | 0.1 | 0.11 | 0.18 | 6.5 | 3.0 |
| CWT30LF | 1.0 | 6.0 | 11.0 | 15.0 | 0.05 | 0.055 | 0.09 | 6.5 | 3.0 |
| CWT60LF | 0.5 | 12.0 | 11.0 | 15.0 | 0.025 | 0.022 | 0.045 | 6.5 | 3.0 |
| CWT150LF | 0.2 | 30.0 | 11.0 | 15.0 | 0.01 | 0.011 | 0.018 | 6.5 | 3.0 |
| CWT300LF | 0.1 | 60.0 | 11.0 | 10.0 | 0.007 | 0.008 | 0.012 | 6.5 | 3.0 |
| CWT600LF | 0.05 | 120.0 | 11.0 | 5.0 | 0.007 | 0.008 | 0.012 | 6.5 | 3.0 |
| CWT1500LF | 0.02 | 300.0 | 11.0 | 4.0 | 0.007 | 0.008 | 0.012 | 10.0 | 5.0 |
Miniature Coils
| Model | Sensitivity (mV/A) | Peak current (kA) | di/dt(kA/μs) | Noise (mV pK-pK) | Droop (%/ms) | Low-frequency bandwidth (3dB), Hz | Phase lead @50Hz (deg) | High-frequency bandwidth (3dB), MHz · 100mm coil | High-frequency bandwidth (3dB), MHz · 200mm coil |
|---|---|---|---|---|---|---|---|---|---|
| CWT03LF | 100.0 | 0.06 | 0.4 | 16.0 | 10.2 | 11.0 | 18.6 | 5.0 | 4.0 |
| CWT06LF | 50.0 | 0.12 | 0.8 | 16.0 | 5.1 | 5.6 | 9.3 | 12.0 | 7.5 |
| CWT1LF | 20.0 | 0.3 | 2.0 | 15.0 | 2.2 | 2.3 | 4.0 | 12.0 | 7.5 |
| CWT3LF | 10.0 | 0.6 | 4.0 | 15.0 | 1.0 | 1.1 | 1.7 | 12.0 | 7.5 |
| CWT6LF | 5.0 | 1.2 | 8.0 | 15.0 | 0.5 | 0.55 | 0.85 | 12.0 | 7.5 |
| CWT15LF | 2.0 | 3.0 | 14.0 | 15.0 | 0.2 | 0.22 | 0.35 | 12.0 | 7.5 |
| CWT30LF | 1.0 | 6.0 | 14.0 | 15.0 | 0.1 | 0.11 | 0.18 | 12.0 | 7.5 |
| CWT60LF | 0.5 | 12.0 | 14.0 | 15.0 | 0.05 | 0.055 | 0.09 | 12.0 | 7.5 |
| CWT150LF | 0.2 | 30.0 | 14.0 | 15.0 | 0.02 | 0.022 | 0.035 | 12.0 | 7.5 |
| CWT300LF | 0.1 | 60.0 | 14.0 | 15.0 | 0.01 | 0.011 | 0.018 | 12.0 | 7.5 |
| CWT600LF | 0.05 | 120.0 | 14.0 | 10.0 | 0.007 | 0.008 | 0.012 | 12.0 | 7.5 |