September 13th, 2018, Published in Articles: Energize

Information from Schneider Electric

The E-Series solid dielectric Automatic Circuit Recloser (ACR) represents Schneider Electric’s commitment to improved products and ongoing product development. It provides the benefits of up-to-date design optimised for automation, remote control and monitoring, now and in the future. After careful evaluation of customers’ needs, the E-Series was developed to achieve performance using technology in solid dielectrics, vacuum interruption and microelectronics.

The E-Series circuit breaker is controlled and monitored by an advanced monitoring and control (ADVC) module.

ADVC is enclosed in a 316-grade stainless steel enclosure which provides an electronic controller with operator interface (OI) that monitors the circuit breaker and performs protection, measurement, control, and communication functions. The switchgear circuit breaker and ADVC are connected via a control cable and they form a remotely controlled and monitored ACR.

The switchgear is operated by a magnetic actuator which produces an opening and closing action. When closed, the switch is latched magnetically. Spring-loaded push-rods provide contact loading on the interrupters. Current transformers and resistive voltage dividers are moulded into the epoxy-housing. These are monitored by the ADVC for protection, remote monitoring, and network status display.

An auxiliary voltage supply of 115/230 V AC is required to power the ADVC. Where this is inconvenient, an additional voltage transformer can be provided. Mounting brackets for lightning arresters are optionally available. The switchgear contact position is shown by a large, clearly visible on/off indicator. The ACR is fitted with a mechanical trip ring which allows for normal operation, manual tripping and locking the recloser in open position.

The E Series ACR is type tested in accordance with IEC with the following characteristics:

• Rated maximum voltage 38 kV
• Rated continuous current 800 A
• Short time withstand current 16 kA
• Rated lightning impulse withstand voltage 170 kV
• Circuit breaker class M2 and E2

Benefits

E-series reclosers have various benefits to the electrical distribution networks in South Africa and even beyond which includes but not limited to the following:

Reduced purchase costs

• No requirement for additional remote terminal unit (RTU), power supplies, batteries, or enclosures. The RTU and a range of communication ports are included in the standard equipment.
• Schneider Electric ACRs are suitable for feeder circuit breakers in outdoor primary substations.

Reduced installation costs

• Configuration of the unit can be done via Windows switchgear operating software or OI.
• Optimal design for pole mounting brackets and an optional voltage transformer for auxiliary supply.

Reduced operating costs

• Reduced equipment damage and low maintenance equipment minimises operating cost.
• ACR is integrated with current and voltage sensors without the need for additional measurement devices.

Smart grid ready

• With the increasing push for advanced monitoring, reduction of outages and the need to facilitate two-way communications between supply and the distribution network, the E-Series solid dielectric recloser is ready to be integrated into smart grid solutions.
• When used with a compatible advanced distribution management system (ADMS or DMS), Schneider Electric ACRs support remote control and monitoring.

Contact Prisca Mashanda, Schneider Electric, Tel 011 254-6400, prisca.mashanda@schneider-electric.com