What is a CT Chamber?

A CT Chamber houses current transformers for low voltage metering applications. 

They are required to transform high voltage to low voltage for your multi-occupancy residential or commercial property.

When the supply to a site needs to be greater than 100 A (~70 kVA at 415 V) then the electricity meter works with current transformers (CTs) housed within their own enclosure – the CT chamber. 

The power cables come onto the site, via a cut-out unit, into the CT Chamber and the Meter Operator typically mounts their meter on the CT chamber.

The Ritherdon CT Chamber:

The Ritherdon CT Chamber is an insulated enclosure made to mount the electricity meter and to house the CTs, and is a tamper proof and sealable unit. However, it is designed with safety in mind along with quick and easy installation. The Enclosure is supplied separately to the backplate so that weight is not an issue. The backplate is easily secured inside the enclosure after it has been mounted onto the cut-out and fixed to the wall. The individual covers, which protect the electrician and allow work to be carried out in the CT Chamber on one phase without having to isolate the complete unit.

CT Chamber for Building Network Operators (BNOs):

The Distribution Network Operator (DNO) will not be responsible for the risers and laterals to multi-occupied buildings. Accordingly, the electrical contractor will be required to install their own electrical connection within the building. Areas which often prove to be very challenging are the installation of CT Panels.

CT wiring and P283 commission testing is required by the Meter Operator and Energy Supplier. Correct metering type current transformers, connection and secondary wiring of CTs and incorrect tail size can lead to delays in meters being installed and ultimately a delay in the customer building being energised by the Meter Operator or DNO.

Benefits to using the Ritherdon CT Chamber:

• Designed to accommodate 100 A – 600 A supplies.
• Proven track record as the ‘top of the range’ unit for installation, quality and safety features in the southeast of England.
• Intuitive Design – Flexibility.
• Built-in flexibility, so they can be installed in a variety of positions to accommodate incoming supply from either the top or the bottom.
• The front panel can be hinged from either side to accommodate local space and access requirements.
• Avoids the requirement for costly lugging of tails.  Our CT panels are designed to accept sector stranded, sector solid or rounded stranded conductors.
• The meter operator can house their meter on the front panel. This avoids requirement for further meter panels and the complexity of running multicore wiring to adjacent locations.
• Accepted by all meter operators.