Overview
The Electrocorder CT-1A is a single-phase current logger for monitoring circuit loading, appliance current, lighting loads and small current trends.
Use it when you need to record current over time on a single conductor, such as an incoming supply, lighting circuit or individual load. The CT-1A uses a split-core current transformer that clips around the conductor, so the supply normally does not need to be interrupted.
Best for:
- Single-phase current logging on accessible circuits.
- Checking load changes after lighting or equipment upgrades.
- Monitoring smaller current ranges from 0.1 A to 100 A, model dependent.
- Earth leakage trend checks where the current is within the suitable range.
- Temporary current monitoring where voltage and power are not required.
Consider another model if:
- You need current ranges above the CT-1A range, where the CT-3A-RS may be more suitable.
- You need voltage, power or energy as well as current, where the CT-2VA, EC-2VA or AL-2VA may be a better fit.
- You need three-phase current monitoring, where the CT-3A-RS or EC-3A-RS may be more appropriate.
What you get:
- CT-1A logger.
- One clamp-on current transformer, USB lead, carry case, batteries, user instructions and free Electrosoft analysis software.
- A compact current logger for circuits where one conductor can be accessed safely.
Set up the logger in Electrosoft before visiting site, fit the current transformer around the conductor being monitored, then start recording. When enough data has been captured, disconnect the logger, connect it to a PC by USB and use Electrosoft to view, save, export and report on the results.
Applications
Typical applications: The CT-1A is intended for current-only investigations where a single conductor can be accessed, commonly at a fuse board, switchboard or distribution board.
What the CT-1A records:
- Single-phase current using a clamp-on current transformer.
- Minimum, maximum and true average current values over the selected averaging period.
- Current trends for load surveys, lighting checks and circuit monitoring.
- Data that helps show whether a current change is sustained or intermittent.
Why constant sampling matters: many instruments only take periodic snapshots. The Electrocorder continuously samples throughout the averaging period, helping capture short events, changing loads and trend data that can otherwise be missed.
Recording duration depends on the selected averaging period. The logger can be configured before the site visit and then left to record current trends.
The CT-1A is normally installed by a competent person because access to individual conductors is required. The current transformer clips around the conductor and does not require the main circuit to be broken.
Case Studies
These related Electrocorder case studies, application pages and articles show how this type of logging is used in practical investigations.
Energy Auditing
A knowledge page explaining how recorded electrical data supports energy audits, load profiling and evidence-based recommendations.
Saving Energy in Industry
An application page focused on measurement, ongoing logging and identifying where energy reductions may be possible.
Recording Electrical Energy Use is Easy
An article explaining how Electrocorder loggers and Electrosoft help capture, review and report recorded electrical data.
Resources
Documentation:
Download the CT-1A datasheet and user instructions for detailed technical information, installation guidance and operating instructions.
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Datasheet |
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User Instructions (English) |
Free Electrosoft PC software
Electrosoft is compatible with Windows 11 down to Windows 7. It lets you view and zoom current, power and energy graphs, export data to Microsoft Excel, email results to colleagues, and print or save reports as PDF files with your company logo.
Electrosoft includes statistics, load balancing, tariff and costing analysis, annual CO2 and energy usage projections, logger management and calibration management tools. Sample files are included so you can try the software without having a logger connected.
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Download Electrosoft PC software |
Features
When to choose the CT-1A
Choose this model when the main question is how much current a single-phase circuit carries over time and a clamp-on CT is the right physical fit.
Compare with related Electrocorder models
If current ranges of 3 A to 400 A are needed, consider the CT-3A-RS. If voltage, power or energy are required as well as current, consider the CT-2VA or EC-2VA.
Key features:
- Single-phase current logging with a split-core current transformer.
- Model-dependent ranges from 0.1 A to 100 A.
- Useful for load checks, lighting studies and small circuit monitoring.
- No voltage connection required for current-only logging.
- Constant sampling to reduce the risk of missing short-duration or changing load events.
Measurement note
The CT-1A is a current logger. It does not measure voltage, power or power factor by itself.
Included with your single-phase current logger with clamp-on current transformer:
- CT-1A logger.
- One clamp-on current transformer, USB lead, carry case, batteries, user instructions and free Electrosoft analysis software.
- A compact current logger for circuits where one conductor can be accessed safely.
Determining product order codes:
To specify your Electrocorder select various codes and enter into the boxes in order to create an accurate product code. For example: CT-1A-HD-5H-IP65-SET.
FAQ
When should I choose the CT-1A?
Choose it for single-phase current-only monitoring where one conductor can be safely accessed and the current range is suitable.
Does the circuit need to be interrupted?
Normally no. The split-core current transformer clips around the conductor.
Does it measure voltage or energy?
No. For voltage, power and energy, consider CT-2VA, EC-2VA or AL-2VA depending on the application.
What current ranges are available?
The CT-1A family covers relatively small loads, model dependent, from 0.1 A to 100 A.
What software is used to analyse the data?
Electrosoft PC software is used to configure the logger, download recorded data, view graphs, export data and create reports.