Product Overview

Ring Main Unit C-GIS Three-Phase The three-phase CT is full-enclosed in the flame retardant plastic shells, primary bushing or cable can pass through the inner hole, bottom has installation inserts for fixation. It is simple and shortcut, is suitable for measuring current, signal collection and protective relaying in the medium voltage power system of bushing or cable etc.

Key Features

•  Fully Sealed Epoxy Cast Insulation：Vacuum-cast IP68-rated enclosure allows continuous submersion up to 1 meter underwater. Insulation material meets UL94 V-0 flame retardancy, withstanding -40°C to +120°C thermal cycling and UV aging resistance. Ideal for harsh environments including coastal areas, deserts, and chemical plants.

•  Wide-Range Multi-Tap Configuration：Covers ratios from 50/5 to 4000/5A with four built-in tap windings (e.g., 200/5A, 400/5A, 800/5A, 1600/5A), switchable via pluggable links. Dynamic response ratio of 1:200 maintains linearity from 0.5% rated current to short-circuit current (20kA).

• Ultra-Low Power Consumption & Energy Saving Design：No-load loss ≤0.8VA, load loss ≤0.2VA, reducing energy consumption by 40% compared to conventional CTs. Secondary windings use high-conductivity oxygen-free copper with 30% increased cross-sectional area to minimize heat generation and losses.

•  Fast Transient Response Characteristics：Special magnetic circuit design prevents core saturation under short-circuit 冲击 with remanence coefficient ≤10%. Protection winding response time ≤8ms, providing reliable signals for high-speed protection systems such as differential and distance relays.

Technical Data

• Rated secondary current:  5A,1A

• Power frequency withstand voltage: 3kV

• Rated frequency:  50/60Hz

• Installation site:  Indoor

• Technical standard:  IEC 60044-1 (IEC 61869-1&2)

Specification