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PEM Rogowski AC Current Probes, CWT, LFR, RCTi,
RCTrms, RCT1A  
Tabs
 
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.

CWT Ultra Mini AC Current Probe
A Rogowski Coil thin enough to fit between the legs of a T0220 semiconductor device. Insertion impedence < 5pH.
   
CWT Ultra Mini AC Current Probe Overview
Model Version New
Peak Current 30A to 6kA
Bandwidth 3.2Hz to 30MHz
Output ±6V fs
Accuracy ±2.0% Typical (calibrated to ±0.2%)
Voltage Isolation 1.2kV peak
Coil Cross Section 1.6mm
Coil Circumference 80mm (standard), 350mm max
Output Connector BNC (0.5m BNC-BNC cable included)



CWT Mini/MiniHF AC Current Probe
A miniature clip around coil capable of monitoring currents in difficult to reach conductors of densely packed power connectors. The MiniHF version adds electrostatic shielding providing excellent immunity to interference from fast local dV/dt transients or high 50/60Hz voltages, and extending high frequency bandwidth to 30MHz. Special cryogenic versions of the CWT Mini are available
CWT Mini/MiniHF AC Current Probe Overview
Peak Current 30A to 30kA
Bandwidth 0.03Hz to 30MHz
Output ±6V fs
Accuracy ±2.0% Typical (calibrated to ±0.2%)
Voltage Isolation 2kV or 5kV peak (MiniHF is 5kV only)
Coil Cross Section 3.5mm (2kV isolation) or 4.5mm (5kV isolation)
Coil Circumference 100 or 200mm (standard), 1500mm max (Mini), 300mm max (MiniHF)
Output Connector BNC (0.5m BNC-BNC cable included)


CWT AC Current Probe
The CWT is ideal for power electronics development work because it combines an easy to use thin, flexible, clip-around coil with an ability to accurately replicate fast switching current waveforms.
CWT AC Current Probe Overview
Peak Current 30A to 300kA
Bandwidth 0.03Hz to 16MHz
Output ±6V fs
Accuracy ±1.0% Typical (calibrated to ±0.2%)
Voltage Isolation 10kV peak 
Coil Cross Section 8.5mm (14mm with sleeve)
Coil Circumference 300, 500, 700, 1000mm (standard), 10,000mm max
Output Connector BNC (0.5m BNC-BNC cable included)

CWTLF AC Current Probe
Available with standard CWT Coils. 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.
CWTLF AC Current Probe Overview
Peak Current From 60A to 300kA
Bandwidth From 0.0038Hz to 12MHz
Output ±6V fs
Accuracy ±1.0% Typical (calibrated to ±0.2%)
Voltage Isolation 10kV peak
Coil Cross Section 8.5mm (14mm with sleeve)
Coil Circumference 300, 500, 700, 1000mm (standard), 10,000mm max
Output Connector BNC (0.5m BNC-BNC cable included)


LFR Dual Range AC Current Probe
A dual range, clip-around, battery powered Rogowski probe for general purpose ac power measurements. The LFR has a 10:1 switch
selectable current ratio to give a wide dynamic range in a single probe.
LFR Dual Range AC Current Probe Overview
Peak Current 60A/600A to 6/60kA
Bandwidth 0.07Hz to 1MHz
Output ±6V fs
Accuracy ±1.0% Typical (calibrated to ±0.3%)
Voltage Isolation 2kV 
Coil Cross Section 8.5mm (14mm with sleeve)
Coil Circumference 300, 500, 700 or 1000mm
Output Connector BNC (0.5m BNC-BNC cable included);
Optional 0.5m BNC to Banana Plug cable available


CMC Common Mode Current Probe
A clip-around, current probe to measure high frequency common mode currents which flow from a variable speed motor drive to ground via the bearings in AC drive systems. The CMC can also be used for in other applications where high frequency currents need to be measured in a background of low frequency current.

Variable Speed Drives (VSDs) used to control AC motors can produce high PWM voltage on the windings that can capacitively couple to the machine shaft. The voltages can be sufficient to cause arcing currents to flow from the shaft through the motor bearings to ground These arcing currents can be measured using a CMC probe.

LFRLFR CMC

 

CMC Common Mode Current Probe Overview
Peak Current 37.5A to 150A
Bandwidth 1.9kHz to 14MHz (1000mm coil)
Output ±7.5V fs
Accuracy ±3.0% Position Variation;
0.05% Linearity
Voltage Isolation 10kV 
Coil Cross Section 8.5mm (14mm with sleeve)
Coil Circumference 500, 700, 1000, 2000, 3000
or 4000mm;
longer lengths available upon request
Output Connector BNC (0.5m BNC-BNC cable included);


RCTi, RCTi-3PH, RCTrms, and RCT1A Current Probes


Optional Diecast IP65 Aluminum Enclosure for RCT Series.

AC Rogowski Coils with a DIN Rail Mounted Integrator for permanent or
semi-permanent installation on equipment. They are exceptionally simple to retrofit into existing plant.





RCT AC Current Probes Overview - Single Phase
Model PEM RCTi
RCTi
PEM RCTi
RCTrms
PEM RCTi
RCT1A

Rated Current (rms) 250A to 50kA 100A to 50kA 500A to 50kA
Bandwidth 0.6Hz to 600kHz 2Hz to 100kHz From 0.06Hz to 5kHz
Output ±5Vrms fs 4 to 20mA fs 1Arms fs
Accuracy ±1.0% ±1.5% ±1.0%
Voltage Isolation 2kV peak
Coil Cross Section 8.5mm 
Coil Circumference 300, 500 or 700mm
Number of Coils 1 1 1
Output Connector Screw Terminals

RCT AC Current Probes Overview - 3-Phase
Model PEM RCTi
RCTi-3ph
PEM RCTi
RCTrms3ph
Rated Current (rms) 250A to 50kA 100A to 50kA
Bandwidth 0.6Hz to 600kHz 2Hz to 100kHz
Output ±5Vrms fs 0-5Vrms or 4 to 20mA fs
Accuracy ±1.0% ±1.5%
Voltage Isolation 2kV peak
Coil Cross Section 8.5mm 
Coil Circumference 300, 500 or 700mm
Number of Coils 3 3
Output Connector Screw Terminals

Features
Applications
  • Peak Current ratings from 30A to 300kA
  • 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 0.1Hz to 30MHz
  • Both battery (4xAA) and external DC power supply
  • CE marked
  • Special cryogenic versions
  • Special long coil versions
  • Monitoring current waveforms in semiconductor switches
  • Development, test and servicing of power electronic equipment.
  • Pulsed Power capacitor discharge and magnetic accelerator current measurements
  • Welding, motor drive, generator, currents
  • Ground currents in rotating machine shafts
  • Induction heating and plasma current measurements
  • Measuring AC currents in the presence of large DC currents
  • Fault monitoring, circuit breaker interuption and lightening strike currents
  • Monitor Battery and Capacitor Ripple Current

Last updated on 8 February, 2017
 
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