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CTA3ph flexible current sensing current transformers with 5A output, allowing fast install without moving or reconfiguring busbars and feeder cables

CTA3ph Models Range from 0-100A up to 0-10000A with high accuracy 0-5A output, driving cable distances from 1m (3ft) to 500m (1640ft) are possible

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CTA3ph, 5A output Rogowski Coil, current sensor
  • Flexible Rogowski current sensor
    Uses the latest Flexible Core 5A output Rogowski Coil sensing technology, UV resistant models for outdoors
  • Compact high accuracy sensors from 1% to 125% of range
    Current Sensors will fit in tight spaces
  • Split core clip-together for fast install
    Quick fitting capability allows for live installs or short shutdown period
  • 2.5VA, 5VA or 7.5VA rating
    To suit all sensor to meter distance requirements from 1m to 500m

The CTA3ph flexible current transformers are the world's first flexible 'clip-on' current probe with a 5A 5VA output, allowing compatibility with existing 5A metering circuits. Unlike conventional CTs, there are no open circuit hazards - ideal for retrospective metering projects and installations in confined spaces where installation of conventional iron core CTs is not possible. The CTA3ph 5A output Rogowski Coil current sensing, simplifies installation and eliminates the need for expensive LV/HV plant shutdowns. In addition, the CTA modules can be used to convert any voltage output current measuring device to a 1A or 5A secondary.

The CTA3ph flexible current transformers convert ac current to an isolated 0-5A current with available ranges from 100A to 10,000A. Because the current sensors are flexible split core, installation is possible without shutting down the LV electrical supply, avoiding expensive down-time costs. Typical applications are retrospective energy monitoring include hospitals, banks, offices buildings, where Energy Management, power, energy and current monitoring is important. For all CTA3ph current sensor models, a NIST/NPL (UKAS) traceable calibration certificate and certificate of conformance is supplied. All CTA3ph sensors use UL94V0 or CSA approved materials. The CTA3ph flexible current sensors are suited to permanent or semi permanent installation. The coil sensor is durable, lightweight, flexible and will easily clip-around a power cable - even in confined spaces. The 5A output from the CTA3ph current sensor connects direct to installed metering, rotary metering or current transducers.

CTA3ph facts and important application information

  • Uses the latest 5A output Rogowski Coil current sensing technology
  • Suitable for single or three phase systems
  • Available sense coil diameters 100mm, 150mm, 200mm, 300mm
  • Isolated measurement outputs
  • 5Arms metering compatible output at 2.5VA, 5VA or 7.5VA
  • 1kV insulation continuous (tested 7.4kV)
  • Available as 0.25%, 0.5%, and 1% accuracy class
  • Wide measurement range from 1% to 125% of range
  • Flat frequency response from 25Hz to 500Hz
  • 110Vac-240Vac power supply, optional 24Vdc, 48Vdc or 125Vdc
  • Operating range -20°C to +45°C, sensors +80°C
  • Safety EN61010-1 1000Vac CATIII, 600Vac CATIV CE marked, UL94V0 flame retardant
  • Options for Energy Monitoring and Power Quality Analysis
  • Allows fast installation, supervised live installs
  • Accreditation certificate and calibration data
  • Live installs are possible, CTA3ph has no open circuit voltage CT hazards
  • Install without shutting down the LV electrical supply, avoiding expensive down-time costs
  • Retrospective energy monitoring include hospitals, shopping centres, banks, server farms, marine/ship
  • Allowing compatibility between Energy Management Systems and older legacy metering
  • Power, energy and current monitoring on renewables
  • Fast response feedback signal for active harmonic cancellation and filters
  • The CTA3ph flexible current sensors are suited to permanent or semi permanent installation
  • The coil sensor is durable, lightweight, flexible and will easily clip-around a busbar or 3ph feeder
  • Suited to installations where conventional CTs are too large
  • CTA3ph/100/5A/5/100 1%
    =100A 5Aout 5m 100mm-dia Class 1
  • CTA3ph/200/5A/3/100
  • CTA3ph/300/5A/3/100
  • CTA3ph/400/5A/3/100
  • CTA3ph/500/5A/3/100
  • CTA3ph/600/5A/3/100
  • CTA3ph/700/5A/3/100
  • CTA3ph/800/5A/3/100
  • CTA3ph/1000/5A/3/100
  • CTA3ph/1200/5A/3/160
  • CTA3ph/1500/5A/3/160
  • CTA3ph/1600/5A/10/160 0.5%
    =1600A 5Aout 10m 160mm-dia Class 0.5
  • CTA3ph/2000/5A/3/160
  • CTA3ph/2500/5A/3/160
  • CTA3ph/3000/5A/3/160
  • CTA3ph/3500/5A/3/160
  • CTA3ph/4000/5A/3/160
  • CTA3ph/5000/5A/3/160
  • CTA3ph/6000/5A/3/160
  • CTA3ph/7000/5A/3/160
  • CTA3ph/8000/5A/3/160
  • CTA3ph/10000/5A/3/160

Cable lengths from sensor to conditioner (3, 5, 10 metres), available up to 21.3m/70ft
CTA3ph, CTA-LD up to 1kM / Arms current / 5A output / cable length / coil diameter mm / Accuracy Class %
Optional voltage input versions (no sensor) TA3ph/5V-5A and TA1ph/5V-5A

CTA3ph 0-5A output "Rope Type" Flexible Current Sensor Specifications

The Powertek CTA3ph flexible sensor & conditioning module are supplied as calibrated sets with a traceable calibrated 0-5Arms output. In addition, these modules can be configured to convert any voltage output current measuring device to a 1A or 5A secondary.

Current Sense coil
  • Diameters: 100mm/3.85", 160mm/6.2”, 220mm/8.6”, and 300mm/11.7" clip-around sensor, split core construction
  • Sensor Thickness: 8mm/0.31"
  • Material: Flexible Thermoplastic rubber, flame retardant UL94V0
  • Working voltage: 1000V at 50/60Hz CAT III, tested 7400V 50/60Hz 1 minute
  • 1000V UL style 20940, 5mm dia, 3metre length
  • Casing: Din Rail module UL94V0 and CSA approved polycarb, 250mm total length
  • Fundamental Frequency: 20Hz to 500Hz
  • Bandwidth: 20Hz-500Hz CTA3ph 5A
  • Bandwidth: 20Hz-2500Hz CTA3ph 1A
  • Output rating: 2.5VA (0.1ohm burden) or 5VA (0.2ohm burden)
  • Phase shift: <0.04° at 50/60/400Hz
  • Accuracy options: <0.25, <0.5%, <1.0%
  • Input impedance: 100kohm
  • Accurate with waveform crest factors: 1.4 - 5
  • Input ranges: From 0-100A to 0-10,000Arms
  • Power: 110Vac-240Vac power, optional 24Vdc, 48Vdc and 125Vdc
  • Includes: Din Rail, PSU and output CT (5A)
  • Operational range -20°C to +65°C

All products have CE, IEC, EN, ASME or BS approvals

Click here for CTA3ph Datasheet Click here for CTA3ph User Manual
CTA3ph sense coil
CTA3ph flexible "rope-type" current transformer, sensing current from 100A to 10,000A with 5A secondary Capable of driving 70ft of 16 AWG cable Capable of driving 32ft of 18 AWG cable Not frequency sensitive
cta3ph, 5A output Rogowski current sensor
CTA3ph Din Rail Assembly: Output transformer / Conditioner Power Supplies /
Powertek specializes in the design and manufacture of electrical power, voltage and current measuring instrumentation
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