One of the most frequently asked questions in our tech support department is this: “Can I get CTs with longer leads or extend the leads myself? What’s the maximum length for CT leads?”
Standard lead length for a DENTcurrent transformer is 3 meters (with a 7 meter option available for some models). 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. Note that the length recommendations listed below apply to PowerScout Series and ELITEpro XC instruments ONLY. To extend RoCoil leads for use with the TCA-5, please contact Tech Support to get advice specific to your application.
For questions outside the scope of this post, please contact DENT Technical Support.
Split-Core / Hinged Split-Core Current Transformers (Including Revenue Grade Hinged Split Cores)
MAXIMUM LENGTH
Split-Core Current Transformers leads can be extended up to 500 feet 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 @ $1/foot using part number WIRE 20 AWG TWPR
- Wire may be purchased in 1000 foot spools from Interconnect Sales with part number UL1015-20-0-9-Twist
RECOMMENDED SPLICING METHOD/MATERIALS
Sure-Connect sealed butt splices from McMaster-Carr (part 9895K13) which 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 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 @ 1.50/foot using part number CBL ROCOIL
- RoCoil mV ONLY: DIY splicing is not advised for RoCoil mV CTs. Contact us for details.
RECOMMENDED SPLICING METHOD/MATERIALS (“BARE ROCOIL ONLY)
Sure-Connect sealed butt splices from McMaster-Carr (part 9895K11) which require a crimping tool and hot air gun. Always follow manufacturer’s instructions.
Solid Core (Toroid) Current Transformers
MAXIMUM LENGTH
Solid Core (Toroid) CT leads can be extended up to 500 feet using extensions of the same wire type/AWG.
WIRE TYPE
UL1015 24 AWG 7 Strand Black & White Twisted Pair (1 twist per inch), 600V rated
PURCHASING OPTION
DENT does not currently stock this wire. It can be purchased by the spool (10,000 ft) through Interconnect Sales.
RECOMMENDED SPLICING METHOD/MATERIALS
Sure-Connect sealed butt splices from McMaster-Carr (p/n 9895K11) which require a crimping tool and hot air gun. Always follow manufacturer’s instructions.
FOR MORE INFORMATION
To download a PDF copy of this information, click here.
If you would like to order lead wire or need more information on CT lead extensions, please do not hesitate to contact DENT Sales or Technical Support.