Since the introduction to the market place and following extensive field testing of the pullkey the South Wales-based electrical engineering company has added a number of innovative features to the initial design.

The latest of these is the new removable entry gland plate which can accommodate the various means of cable connections as required by contrasting application requirements.

The plate can be provided with entries to suit the appropriate sockets or glands and the front cover is secured by one quarter turn captive screws enabling easy access for maintenance or trouble shooting.

In recent months the robust stainless steel Pullkey unit, which is available in taut or slack wire configuration, has been installed on six conveyor systems at a number of mines in the Hunter Valley NSW and the Bowen Basin in Queensland and in most cases the iMAC signal line system was included in the conveyor control package.

Positive feedback has been received on the robust IP66 stainless steel construction of the new pullkey and its mechanism which also consists predominately of stainless steel components. This has also extended to the inner housing area which provides room for auxiliary items for control and monitoring purposes, minimising the need for additional junction boxes.

The pullkey design employs a modular concept that allows full integration with the Ampcontrol iMAC system to streamline the addition of further operational functions. In cases where only fundamental switching and indication applications are required, the basic pullkey unit is utilised. However, if the iMAC monitoring and control capability is required, a purpose built circuit board is fitted to the pullkey as well as the appropriate fascia incorporating relevant switches and necessary LEDS.

Currently being installed at the Mannering Colliery south of Newcastle, is a taut wire system that utilises the full capability of the pullkey – this incorporates the remote isolation and signaling functionality via the Ampcontrol iMAC monitoring and control system and the pre start warning function.

Ronald Newell, who has just recently taken up the position of product manager - control and monitoring systems, was heavily involved in the development of the new pullkey and has subsequently overseen the initial system installations undertaken at the Dartbrook colliery in the Hunter Valley.

“When combined with the iMAC system, the total package provides powerful capabilities in signaling, monitoring and control, as well as bringing an increased level of safety to operational personnel,” Newell said.

“Market research has enabled us to design and deliver a product to the market with flexibility and adaptability to meet the individual needs of each customer.”