Provided is a compressor control unit with a high response ability to changes of gas condition of a compressor. Storing the row address frees testing from being limited to activating at one time only rows related to a common redundant segment. purification plants and waste products from the industry, and having a determined chemical composition adjusted on basis of knowledge of the chemical composition of the mineral-containing components forming part of the glass. This document also describes a method of manufacturing such an instrument guide, which is also applicable to manufacturing an instrument guide providing parallel lumens.