USD

Product, Order & General Inquiries +1 (800) 663-7845 (8am-4:30pm PST)

Your cart is currently empty.

Clamp-on AC Current Transducer - 250 Amps 50/60Hz - (CT-253)
Ask a Product Question Request a Quote Technical Support
Call ACR Now Call ACR: 1-800-663-7845
North America: 1-800-663-7845
International: +1-604-591-1128
Mon–Fri 8:30 AM – 4:30 PM PT

Clamp-on AC Current Transducer - 250 Amps 50/60Hz - (CT-253)

The CT-253 is a 250 A AC clamp-on current transducer designed for safe, accurate measurement of electrical current in power distribution systems. It connects directly to the SRX3 AC Current Data Logger, SmartReader Plus 3, or the CAL Compressed Air Logger to convert live AC current into a proportional signal the logger can record. With its split-core design, the CT-253 installs easily without disconnecting wires or interrupting power — perfect for energy audits, load studies, HVAC system testing, and long-term performance monitoring.

Key Features

  • Clamp-on design – Non-intrusive installation without breaking the circuit.
  • 250 A AC range – Ideal for branch circuits, motors, and equipment loads.
  • Output: 0–5 V DC proportional to measured current.
  • Safe and durable – Molded housing with insulated jaws for dependable field use.
  • Compact form factor – Fits easily in panels or tight enclosures.
SKU: 35-0048
$309.00 USD

Guaranteed safe checkout

american expressdiners clubdiscovermasterpaypalvisa
Description Specifications Documentation Q&A

Typical Applications

  • Measuring three-phase motor loads and verifying balance.

  • Conducting energy audits and 30-day load studies.

  • Monitoring compressors, pumps, lighting, and HVAC equipment.

  • Supporting LEED and energy-management documentation.



*A $40 USD shipping fee will be applied to this product.

Specifications

Electrical Specifications

  • Current Range: 5 A to 250 A AC
  • Operating Range: 0.5 A to 250 A AC
  • Output Signal: 0–5 VDC proportional output
  • Frequency Range: 40 Hz to 10 kHz
  • Nominal Operating Frequency: 50/60 Hz
  • Working Voltage: 600 Vrms
  • Common Mode Voltage: 30 Vrms
  • Crest Factor: 3 @ 200 Arms
  • Output Accuracy: ±2.0% to ±3.0% of reading depending on current range
  • Conductor Position Sensitivity: Typically 0.5% output variation

Mechanical Specifications

  • Clamp Opening: 0.83 in (21 mm)
  • Maximum Cable Diameter: 0.78 in (20 mm)
  • Maximum Bus Bar Size: 0.78 × 0.19 in (20 × 5 mm)
  • Cable Length: 5 ft (1.5 m)
  • Dimensions: 5.47 × 2.00 × 1.18 in (139 × 51 × 30 mm)
  • Weight: 180 g (6.5 oz)
  • Housing Material: Polycarbonate, UL94 V0 rated
  • Protection Rating: IP40
  • Mechanical Life: Greater than 50,000 opening operations

Environmental Specifications

  • Operating Temperature: 14°F to 131°F (-10°C to +55°C)
  • Storage Temperature: -40°F to 158°F (-40°C to +70°C)
  • Operating Humidity: 10% to 35% RH without derating
  • Operating Altitude: 0–2000 m
  • Non-Operating Altitude: 0–12,000 m

Safety & Compliance

  • Double insulation / reinforced insulation design
  • IEC 1010-2-32 compliant
  • 600 V CAT III, Pollution Degree 2
  • Dielectric strength: 5550 V, 50/60 Hz
  • CE marked

Compatibility

The CT-253 is compatible with monitoring devices that accept a 0–5 VDC analog input, including the ACR SRX3 AC Current Logger.

Installation Notes

  • Split-core clamp design allows installation without disconnecting wiring
  • Self-powered from the monitored conductor
  • Suitable for load profiling and long-term AC current monitoring applications

Documentation

For a product sheet, please click below for a pdf version.

Product Sheet

Q&A

How do I know if the 250 A range is right for my application?

With a range of 0-250 Amps, the CT-253 is well suited for many commercial and industrial circuits, feeder monitoring applications, and equipment load studies where operating currents may approach 250 A.

For best measurement resolution, the selected probe should generally be rated approximately 1.25× to 1.5× higher than the expected maximum operating current. If your application normally operates far below 250 A, a lower-range probe may provide improved measurement resolution. If currents may exceed 250 A, higher-range probes are also available.

ACR offers compatible current probes in multiple ranges, including:

If you are unsure which probe range is most appropriate, contact ACR for assistance selecting a suitable current transducer for your application.

Does the CT-253 require an external power supply?

No. The CT-253 is self-powered from the magnetic field generated by the conductor being monitored and does not require a separate external power source.

Is this probe compatible with my SRX3 AC Current Logger?

Yes it is. The CT-253 outputs a 0-5 Vdc signal which is compatible with the 0-5 Vdc input channels on the SRX3.

How does the CT-253 connect to the SRX3?

The probe connects directly to one of the SRX3’s 0–5 VDC input channels using its analog output leads.

Do I need to disconnect high voltage wiring to install the probe?

No. The split-core clamp-on design allows installation around an existing conductor without disconnecting wiring.

Can multiple probes be used together?

Yes. Multiple CT-253 probes can be connected to multi-channel loggers such as the SRX3 for monitoring multiple circuits or three-phase systems.

{"id":6149853413547,"title":"Clamp-on AC Current Transducer - 250 Amps 50\/60Hz - (CT-253)","handle":"ac-current-transducer-ct-253-250-a-50-60hz","description":"\u003ch3 data-start=\"1614\" data-end=\"1638\"\u003eTypical Applications\u003c\/h3\u003e\n\u003cul data-start=\"1639\" data-end=\"1893\"\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eMeasuring three-phase motor loads and verifying balance.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eConducting energy audits and 30-day load studies.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1766\" data-end=\"1834\"\u003e\n\u003cp data-start=\"1768\" data-end=\"1834\"\u003eMonitoring compressors, pumps, lighting, and HVAC equipment.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1835\" data-end=\"1893\"\u003e\n\u003cp data-start=\"1837\" data-end=\"1893\"\u003eSupporting LEED and energy-management documentation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cbr\u003e\u003cbr\u003e*A $40 USD shipping fee will be applied to this product.\u003c\/p\u003e","published_at":"2020-12-18T20:41:34-08:00","created_at":"2020-12-18T20:41:34-08:00","vendor":"ACR Systems","type":"","tags":["AC Current \u0026 Voltage"],"price":30900,"price_min":30900,"price_max":30900,"available":true,"price_varies":false,"compare_at_price":null,"compare_at_price_min":0,"compare_at_price_max":0,"compare_at_price_varies":false,"variants":[{"id":37804119425195,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"35-0048","requires_shipping":true,"taxable":true,"featured_image":null,"available":true,"name":"Clamp-on AC Current Transducer - 250 Amps 50\/60Hz - (CT-253)","public_title":null,"options":["Default Title"],"price":30900,"weight":0,"compare_at_price":null,"inventory_management":null,"barcode":"","requires_selling_plan":false,"selling_plan_allocations":[],"quantity_rule":{"min":1,"max":null,"increment":1}}],"images":["\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927"],"featured_image":"\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927","options":["Title"],"media":[{"alt":null,"id":15547485749419,"position":1,"preview_image":{"aspect_ratio":1.361,"height":294,"width":400,"src":"\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927"},"aspect_ratio":1.361,"height":294,"media_type":"image","src":"\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927","width":400}],"requires_selling_plan":false,"selling_plan_groups":[],"content":"\u003ch3 data-start=\"1614\" data-end=\"1638\"\u003eTypical Applications\u003c\/h3\u003e\n\u003cul data-start=\"1639\" data-end=\"1893\"\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eMeasuring three-phase motor loads and verifying balance.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eConducting energy audits and 30-day load studies.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1766\" data-end=\"1834\"\u003e\n\u003cp data-start=\"1768\" data-end=\"1834\"\u003eMonitoring compressors, pumps, lighting, and HVAC equipment.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1835\" data-end=\"1893\"\u003e\n\u003cp data-start=\"1837\" data-end=\"1893\"\u003eSupporting LEED and energy-management documentation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cbr\u003e\u003cbr\u003e*A $40 USD shipping fee will be applied to this product.\u003c\/p\u003e"}
Translation missing: en.general.search.loading
{"id":6149853413547,"title":"Clamp-on AC Current Transducer - 250 Amps 50\/60Hz - (CT-253)","handle":"ac-current-transducer-ct-253-250-a-50-60hz","description":"\u003ch3 data-start=\"1614\" data-end=\"1638\"\u003eTypical Applications\u003c\/h3\u003e\n\u003cul data-start=\"1639\" data-end=\"1893\"\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eMeasuring three-phase motor loads and verifying balance.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eConducting energy audits and 30-day load studies.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1766\" data-end=\"1834\"\u003e\n\u003cp data-start=\"1768\" data-end=\"1834\"\u003eMonitoring compressors, pumps, lighting, and HVAC equipment.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1835\" data-end=\"1893\"\u003e\n\u003cp data-start=\"1837\" data-end=\"1893\"\u003eSupporting LEED and energy-management documentation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cbr\u003e\u003cbr\u003e*A $40 USD shipping fee will be applied to this product.\u003c\/p\u003e","published_at":"2020-12-18T20:41:34-08:00","created_at":"2020-12-18T20:41:34-08:00","vendor":"ACR Systems","type":"","tags":["AC Current \u0026 Voltage"],"price":30900,"price_min":30900,"price_max":30900,"available":true,"price_varies":false,"compare_at_price":null,"compare_at_price_min":0,"compare_at_price_max":0,"compare_at_price_varies":false,"variants":[{"id":37804119425195,"title":"Default Title","option1":"Default Title","option2":null,"option3":null,"sku":"35-0048","requires_shipping":true,"taxable":true,"featured_image":null,"available":true,"name":"Clamp-on AC Current Transducer - 250 Amps 50\/60Hz - (CT-253)","public_title":null,"options":["Default Title"],"price":30900,"weight":0,"compare_at_price":null,"inventory_management":null,"barcode":"","requires_selling_plan":false,"selling_plan_allocations":[],"quantity_rule":{"min":1,"max":null,"increment":1}}],"images":["\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927"],"featured_image":"\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927","options":["Title"],"media":[{"alt":null,"id":15547485749419,"position":1,"preview_image":{"aspect_ratio":1.361,"height":294,"width":400,"src":"\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927"},"aspect_ratio":1.361,"height":294,"media_type":"image","src":"\/\/www.acrdatasolutions.com\/cdn\/shop\/products\/3603_400_300.jpg?v=1610163927","width":400}],"requires_selling_plan":false,"selling_plan_groups":[],"content":"\u003ch3 data-start=\"1614\" data-end=\"1638\"\u003eTypical Applications\u003c\/h3\u003e\n\u003cul data-start=\"1639\" data-end=\"1893\"\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eMeasuring three-phase motor loads and verifying balance.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1639\" data-end=\"1703\"\u003e\n\u003cp data-start=\"1641\" data-end=\"1703\"\u003eConducting energy audits and 30-day load studies.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1766\" data-end=\"1834\"\u003e\n\u003cp data-start=\"1768\" data-end=\"1834\"\u003eMonitoring compressors, pumps, lighting, and HVAC equipment.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1835\" data-end=\"1893\"\u003e\n\u003cp data-start=\"1837\" data-end=\"1893\"\u003eSupporting LEED and energy-management documentation.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cbr\u003e\u003cbr\u003e*A $40 USD shipping fee will be applied to this product.\u003c\/p\u003e"}