Representative imageCurrent Sensing CTs (Customised)
Customised current-sensing CTs are application-engineered current transformers designed to a buyer's specific sensing requirement rather than to a standard catalogue ratio.
Overview
Customised current-sensing CTs are application-engineered current transformers designed to a buyer's specific sensing requirement rather than to a standard catalogue ratio. They sense AC (and, for specialised cores, AC-superimposed) current in power-electronics and OEM equipment and deliver a defined, low-level secondary signal — a milliamp current, a low AC voltage, or (with an integrated burden resistor / rectifier) a scaled DC voltage such as 333 mV or 0–5 V DC — proportional to the primary current. They are typically toroidal/ring (window) or split-core/hinged designs so the busbar or cable passes through the core; split-core types clamp on without disconnecting the conductor, easing retrofit. A buyer chooses ACE's customised route when an off-the-shelf CT does not fit: non-standard ratio or turns, a specific core window/ID to clear a busbar, a particular output signal and burden to match a controller or measurement IC input, defined accuracy and phase response over the operating range, or a footprint/mounting dictated by the host equipment. They are commonly embedded in rectifiers, drives, UPS, inverters and harmonic-filter assemblies — including ACE's own power-electronics products — for current feedback, regulation, protection and metering. Standard parameter set and typical ranges for the class (not ACE-specific figures): primary range from a few amps to several kiloamps; output as mA secondary, low-VA AC voltage, or DC voltage via onboard rectifier; turns ratio set to the required output; typical sensing accuracy on the order of ±0.5% to ±1% over a wide dynamic range; frequency 50/60 Hz or wider for power-electronics use; core/window size, mounting (PCB, panel, busbar-clamp) and isolation specified per application.
Specifications
| Primary current range | few A up to several kA (customised to application) |
|---|---|
| Output / secondary signal | mA secondary, low-level AC voltage, or scaled DC (e.g. 333 mV, 0–5 V DC via integrated burden/rectifier) |
| Turns ratio | set to required output (custom, not limited to 5 A / 1 A standards) |
| Core form | toroidal / ring (window) or split-core / hinged (clamp-on, no conductor disconnect) |
| Core window / inner diameter | sized to clear the host busbar or cable bundle |
| Sensing accuracy | typically ±0.5% to ±1% over rated dynamic range (application-defined) |
| Frequency / bandwidth | 50/60 Hz standard; wider range for power-electronics current feedback |
| Mounting | PCB, panel, or busbar/cable clamp per host equipment |
| Isolation / insulation | galvanic isolation; dielectric rating per LT application |
| Output options | with or without onboard burden resistor / rectifier for direct DC reading |
| Customisation | ratio, output, core size, accuracy, footprint and terminations to buyer spec |
Applications
- Current feedback and regulation in rectifiers, drives, inverters and UPS
- OEM / embedded current sensing inside power-electronics assemblies
- Harmonic filter and power-conditioning current monitoring
- Retrofit clamp-on (split-core) sensing without interrupting service
- Energy / power metering and submetering with custom output
- Protection and overcurrent feedback in custom panels and equipment
Frequently asked questions
Do you build custom current transformers to specification?
What quality standard does ACE Electromagnetics work to?
How soon will I get a response to a quote request?
Are the specifications shown on this page final?
Request a quote — Current Sensing CTs (Customised)
Tell us your application and ratings. Our engineering team replies within one business day.
What we need to quote
- kVA / VA or current rating
- Primary & secondary voltage
- Frequency (50 / 60 / 400 Hz)
- Phase (1-ph / 3-ph)
- Cooling, mounting & enclosure (IP)
- Application / end-use
Share what you have — we confirm the rest with you.
