The article presents comparative results of metrological properties of selected current transformers and current -voltage transducers available on the market. Appropriate conclusions were formulated regarding their usefulness in current measuring systems with relatively small values (from 1 A to 30 A) but with a frequency varying from 10 Hz to 550 Hz.

The compact device aiding the of cables and ropes rewinding is described. Such devices are used during rewinding the ropes and cables from the drums, delivered by the manufacturer,  to mine cars for their further transportation. The described cable and rope rewinder  of KUP-01 type, developed by KOMAG, is an option for the currently used technical solutions.

Shield supports are usually perceived as devices consisting mainly of mechanical and hydraulic parts, while other apparatus, mainly related to electronics, is often treated as a necessary supplement to the system which ensures its control. However, the development of features closely related to the latest electronic equipment in the mining complexes, mainly connected with measuring and registration possibilities, also allows for more and more frequent use of various types of monitoring. It enables observation of the operation of the mining complex in real time or with a slight time delay. What is more, it also enables signalling the operating states of the shield constituting specific threats or irregularities. The most advanced systems found abroad are equipped with functions analysing changes in specific monitored parameters to develop warnings about possible future threats to allow the operator to react with sufficient time in advance. Developing such a forecast system requires gathering and then analysing a sufficiently large and complete database of measurements and observations. These are primarily associated with various difficulties in operating a shield support, and especially with strictly emergency states, such as rock slides, shield clamping conditions, etc. The data from monitoring of shield support operation, through proper development of dependencies and analysis results, can optimize the safety of crew, reduce difficulties in maintaining the roof of longwall excavations and thus have a positive impact on the obtained economic results.

In the list of search results implemented as part of the INDIRES public project. The main goal of the implemented project is to improve work safety in mining, by developing new technologies supporting the work of mining rescuers, using innovative communication technologies that can be used in potentially explosive methane and / or coal dust.

Cooling of the machines used in the mining industry, equipped with high-power electric drives, by water from the mine fire system generates technological and economic problems associated with re-transportation of water to the surface. The concept of open and closed system for cooling the high-power mining machines is presented. This is an alternative to the commonly use method. Advantages and disadvantages of the discussed systems are compared.

Method of driving auxiliary rescue tunnels using the small-diameter cutting-loading head, with the pulsating torque of the frequencies selected for the type of mined rock is presented. The head is installed on a drilling platform. The design and main components of the head are presented.