One of the most frequently asked questions we get from electricians is this: “Can I get CTs with longer leads or extend the leads myself? What’s the maximum length for CT leads on DENT EliteProXC or PowerScout?”
Standard lead length for a DENT current transformer is between 6 and 8 feet (about 2m), depending on model. Occasionally, because of electrical room layout or other factors, there is a requirement for longer leads on a current transformer. Therefore, extending the CT leads is necessary. The following is a brief overview of options for extending CT leads based on CT type.
Split-Core / Hinged Split-Core Current Transformers
MAXIMUM LENGTH
Split-core CT leads can be extended up to 500 feet (150m) using extensions of the same wire type/AWG.
WIRE TYPE
600V Rated VW-1, 105°C, 20AWG, black and white twisted pair, cURus
PURCHASING OPTIONS
- Purchase wire by-the-foot for DIY splicing from DENT using part number WIRE 20 AWG TWPR
- CTs spliced at the factory in custom lengths
- Wire may be purchased in 300m spools, choose the equivalent of Interconnect Sales part number UL1015-20-0-9-Twist
RECOMMENDED SPLICING METHOD/MATERIALS
Self sealing butt splices are convenient and reliable. These require a crimping tool and hot air gun. Always follow manufacturer’s instructions.
RoCoil Current Transformers
MAXIMUM LENGTH
RoCoil CT leads can be extended up to 100 feet (30m) using extensions of the same wire type/AWG.
WIRE TYPE
“Bare” RoCoil: Shielded cable with thermoplastic insulation, 1000VAC VW-1, 2x26AWG, 80°C, cURus
PURCHASING OPTIONS
- Purchase wire by-the-foot for DIY splicing from DENT
- Custom Lengths performed at DENT factory
- RoCoil mV ONLY: DIY splicing is not advised for RoCoil mV CTs. Length can be added at the factory.
RECOMMENDED SPLICING METHOD/MATERIALS (“BARE ROCOIL ONLY)
Self sealing butt splices are convenient and reliable. These require a crimping tool and hot air gun. Always follow manufacturer’s instructions.
For more advice on current measurement please contact us.
Article courtesy of DENT Instruments.
