TWS Energy Controls has oil-insulated metering units containing both CT and VT in single or three phase combinations up to 36kV. These can either be pole or ground mounted. The units are designed as a convenient and cost effective means of installing metering class CT and VT into a power supply network.

Metering units can be supplied for 3.6kV, 7.2kV, 12kV, 24kV and 36kV standard systems. Various configurations can be supplied on request. In addition, dual protection and metering functions can be accommodated within the same unit.

Enclosure:

Enclosure is self-draining and is available in the following finishes:

• 316 grade stainless steel
• hot dipped galvanised mild steel.
• Arc Zins coated with paint finish
• Powder coated Mild steel

As standard they are complete with lifting lugs, oil level sight gauge, earth lug, oil filling bung and drain gate valve. All LV connections are brought out into an IP65 secondary terminal box.

Location:

Metering units can be designed for both indoor and outdoor environments.

Current Transformers:

These units can accommodate up to three CTs per phase. Single or multiple ratios are available.

Voltage Transformers:

All VTs are single phase units. (Five limb 3ø equivalent)

VTs are connected YNynO with an optional open delta additional secondary. The high voltage star point is brought outside the tank via a 3.6kV bushing and earthed via a removable link.

Class:

A full range of metering and protection CT and VT classes is available.

Mounting:

Ground or pole mounted. These include base securing and pole hanger brackets.

Terminations

Primary:

Palm terminals on porcelain bushings or cable terminations.

Secondary:

A sealable, weatherproof (IP65) terminal box complete with gland plate, Klippon SAK 6N terminals and HRC fuses.

Protection:

Low voltage HRC secondary fuses are standard. Under oil high voltage primary fuses are available on request.

Testing:

Designed and manufactured to IEC or Australian standards. All metering units are tested in the TWS Energy Controls' high voltage test laboratory and supplied with test certificates to the requirements of the standards.