PEM CWT Mini50HF/CWT Mini/CWTLF Mini AC Current Probe
The PEM AC Current Probes utilize a Rogowski Coil and Matched Analog Integrator to provide accurate non-contact, measurement of AC currents over a very broad frequency range. These flexible “clip-around” Current Probes have very low insertion impedance compared to Current Transformers, (CT), or Hall Current Transducers, are easy to insert in confined spaces and are not damaged by over-current surges. They can be used for measuring ac, pulse or transient current waveforms. Since the PEM Current Probes have no magnetic core they can be used to measure ac current on a conductor with high dc current or in the presence of a high dc magnetic field.
The CWT range is ideal for power electronic applications, such as monitoring semiconductor switching waveforms or for measurements in electrically noisy environments. The easy-to-use thin, flexible, clip-around coil accurately replicates fast switching current waveforms be they sinusoidal, quasi sinusoidal or pulsed.
CWT Mini50HF
The CWT Mini50HF is optimized for faster switching devices such as SiC and has a high frequency (-3dB) bandwidth of 50MHz with a 100mm coil at just 3.5mm thickness (2kV peak insulation). As with CWTMiniHF range it combines an innovative screened Rogowski coil providing excellent immunity to interference from fast local dV/dt transients or large 50/60Hz voltages with excellent high frequency performance.
CWTLF Mini AC Current Probe
The CWTLF provides an extended low frequency bandwidth. This enables the measurement of: low currents at 50/60Hz; AC currents with significantly lower phase shift error, and long pulses of current with lower values of droop than the CWT standard or mini ranges. Measurement range is from 60A to 300kA, with bandwidth from 0.0038Hz to 12MHz.
For pricing on CWTLF with standard length coils, see CWT AC Current Probes.
Features
- Peak Current ratings from 30A to 30kA
- Robust, flexible, clip-around coils
- Integrator included with Rogowski Coil to provide an analog signal accurately proportional to primary current in amplitude and phase
- High voltage isolation and common mode rejection
- Measure ac current even in the presence of a high dc current
- Not influenced by high dc magnetic fields
- Bandwidth from 3Hz to 50MHz for CWT Mini50HF
- Bandwidth from 0.1Hz to 30MHz for CWTLF Mini
- No I*t limitation as with CT
- Both battery (4xAA) and external DC power supply
- CE marked
- Special cryogenic versions
- Special long coil versions
Applications
- Monitoring current waveforms in semiconductor switches
- Development, test and servicing of power electronic equipment.
- Pulsed Power capacitor discharge and magnetic accelerator current measurements
- Induction Heating Cooking Appliances
Tech Support
- CWT Mini50HF Datasheet, revised 2024
- CWT Mini/ CWT Mini HF Datasheet
- CWTLF Datasheet – March 2018 (Includes CWTLF with Mini Coil)
- CWT/LFR-YK Power Cable, 0.5m , For Yokogawa Oscilloscopes and ScopeCorders
Instructions for Use
Mechanical Dimensions
-
- CWT Technical notes – HF and Rise-time – 01A
- CWT Application Notes
- CWT Technical Note – Delay and Rise Time
- Voltage Immunity
- Accurate Power Conversion Measurements on High Power Motor Drives
- Instructions for CWT Integrator Module Fuse Replacement
- Application Note – CWT AC Current Probes – what is minimum recommended current?
- Application Note: Transducer Termination Impedance – Low and High Frequency Analysis
- PEM CWT AC Current Probes (Rogowski Coils) – Equivalents
- “High Performance Rogowski Current Transducers”, W. F. Ray and C. R. Hewson
- “Next-Generation Current Probes for High-Speed and High Power-Density Applications”, Dr Chris Hewson, Power Electronic Measurements Ltd
- “Power Integrity” by Steve Sandler. See Chapters 5: Probes and 7: Measuring Impedance for applications using PEM Rogowski Coils (purchase of book required).
- Measuring Fast Switching Currents with CWT UM, CWT Mini and CWT MiniHF, Dr Chris Hewson, APEC 2015
Pricing
Product Configurator:
Select product options from drop-down menus to quote standard products not normally in stock. For fully custom products, fill in the message box below.
Order Code for CWT Mini50HF: Type / Battery / Cable Length / Coil Circumference / Insulation
For example: CWT Mini50HF 015/B/1/100
For descriptions of the possible selections, please see the Specifications above.
CWT Mini50HF AC Current Probe
Part No. | Description | Price | In Stock |
---|---|---|---|
CWT Mini50HF 3/B/1/100/2 | AC Current Probe, Mini50HF, 10mV/A, 600A, 12Hz-50MHz, Alkali battery 4xAA, 1m cable length from Coil to Integrator, 100mm Coil circumference length, 2kV peak Coil Voltage Isolation, 3.5mm cross section. Includes US13S power supply. | $1,330.00 | |
CWT Mini50HF 15/B/1/200/2 | AC Current Probe, Mini50HF, 2mV/A, 3kA, 3Hz-35MHz, Alkali battery 4xAA, 1m cable length from Coil to Integrator, 200mm Coil circumference length, 2kV peak Coil Voltage Isolation, 3.5mm cross section. Includes US13S power supply. | $1,410.00 | |
CWT Mini50HF 015/B/1/100/2 | AC Current Probe, Mini50HF, 200mV/A, 30A, 150Hz-50MHz, Alkali battery 4xAA, 1m cable length from Coil to Integrator, 100mm Coil circumference length, 2kV peak Coil Voltage Isolation, 3.5mm cross section. Includes US13S power supply. | $1,330.00 | |
CWT Mini50HF 015/B/1/200/2 | AC Current Probe, Mini50HF, 200mV/A, 30A, 150Hz-35MHz, Alkali battery 4xAA, 1m cable length from Coil to Integrator, 200mm Coil circumference length, 2kV peak Coil Voltage Isolation, 3.5mm cross section. Includes US13S power supply. | $1,410.00 |
CWT Mini AC Current Probe
Part No. | Description | Price | In Stock |
---|---|---|---|
CWT MiniHF 1x/B/2.5/120/5 | AC Current Probe, MiniHF, 20mV/A, 300A, optimized for 79kHz to 90kHz, Alkali battery 4xAA, 2.5m cable length from Coil to Integrator, 120mm Coil circumference length, 5kV peak Coil Voltage Isolation, 4.5mm cross section. Includes US13S power supply. | $1,500.00 | |
CWT Mini 1/B/2.5/100/5 | AC Current Probe, Mini, 20mV/A, 300A, 4.8Hz-20MHz, Alkalai battery 4xAA, 2.5m cable length from Coil to Integrator, 100mm Coil circumference length, 5kV Insulation. 4.5mm cross section. Includes US13S power supply. | $1,180.00 |
CWT Mini50HF Accessories
Part No. | Description | Price | In Stock |
---|---|---|---|
US13S | CWT UM Regulated Power Supply. 120VAC, 60Hz, 12V ±10%, 300mA, Barrel type: 1.3 x 3.5 x 10mm. Power disconnects battery when plugged into the integrator. | $40.00 | |
EU13S | CWT UM Regulated Power Supply. 100V-220AC, 50/60Hz, 12V ±10%, 500mA, Barrel type: 1.3 x 3.5 x 10mm. Power disconnects battery when plugged into the integrator. European plug type. | $40.00 | |
UK13S | CWT UM Regulated Power Supply. 100V-220AC, 50/60Hz, 12V ±10%, 500mA, Barrel type: 1.3 x 3.5 x 10mm. Power disconnects battery when plugged into the integrator. UK plug type. | $40.00 | |
PowerCableYK13 | Yokogawa compatible power cord, 0.5m, supports all PEM units fitted with a 1.3mm DC power socket. | $70.00 |
Re-Calibration
Note: Calibration on new product is discounted 50%.
New PEM Rogowski Coils include a Manufacturer’s Calibration Certificate at no extra charge.
Part No. | Description | Price | In Stock |
---|---|---|---|
OL-17025-500A-AC | 17025 Accredited Calibration, Current Transducer, Full-scale Range between 0 and 500Arms, 50-400Hz, https://gmw.com/quality/ | $300.00 | |
OL-17025-500A-AC-ADD | Calibration of Additional Transducer | $150.00 | |
OL-17025-2000A-AC | 17025 Accredited Calibration, Current Transducer, Full-scale Range between 501 and 2000Arms, 50-400Hz, https://gmw.com/quality/ | $400.00 | |
OL-17025-2000A-AC-ADD | Calibration of Additional Transducer | $200.00 | |
OL-17025-8000A-AC | 17025 Accredited Calibration, Current Transducer, Full-scale Range between 2001 and 8000Arms, 50-400Hz, https://gmw.com/quality/ | $500.00 | |
OL-17025-8000A-AC-ADD | Calibration of Additional Transducer | $250.00 |
Repair
Part No. | Description | Price | In Stock |
---|---|---|---|
RECOIL-CWT | Recoil (replace damaged coil) and Recalibrate
| $820.00 |
Terms and Conditions
Quantity Discount Schedule:
Quantity | 1 – 9 | 10 – 24 |
Discount | 0% | 5% |
Terms and Conditions:
Prices above are for domestic deliveries to Canada, USA and Mexico only.
Prices are expressed in U.S. Dollars, FCA San Carlos, California.
Prices are subject to change without notice.
Higher quantity and OEM discounts are available.
Payment:
Visa, MasterCard, Amex, Prepayment before shipment, or Net 30 days (subject to credit
acceptance).
Delivery:
Items in stock shipped next business day. All other items are 8-10 weeks.