Product Line
BCPM, LVCT (Low Voltage Current Transformer)
Environment
Low Voltage Current Transformer Specifications
Resolution
The BCPM uses 1/3 V output split-core CTs for the auxiliary inputs.
The specifications for the 1/3 Volt low-voltage CTs are:
- Accuracy: ±1% from 10% to 100% of rated current
- Frequency Range: 50/60 Hz
- Operating Temperature: -15°C to 60°C
- Storage Temperature: -40°C to 70°C
- Humidity Range: 0–95% non-condensing
- Leads: 18 AWG, 600 Vac, UL 1015 twisted pair, 1.8 m standard length
- Max Voltage (L-N): sensed conductor 600 Vac
The apparent power capacity (burden rating) does not apply since these are voltage-output devices, unlike traditional current-mode CTs. This is a key advantage of voltage-mode CTs (another being that they do not require shorting blocks).
Voltage-mode CTs have an internal burden resistor, typically tens of ohms or less. The meter input monitoring the CT usually has an impedance of tens of thousands of ohms in parallel with the CT’s burden resistor, which may slightly reduce the CT’s output voltage.
As long as the series resistance of the wire between the CT and the meter is less than a few hundred ohms, CT accuracy remains largely unaffected. Voltage-mode CTs can support longer wire runs using smaller gauge wire compared to traditional current-mode CTs.