56 of 124  Construction of Giresun Wastewater Treatment Plant  Tender Dossier Volume 3 Employer’s Requirements  Section 08: Electrical Works  Power cables shall be selected such that the voltage drop does not exceed the maximum value defined in IEC  60364 at any point in the installation.  Power cables shall generally consist of two types:  For Indoors Cables that lead to the facility and machinery will be thermoplastic insulated type NYY, NYCY or NYMHY  type, by using polyvinyl chloride (PVC) or cross-linked polyethylene.  For Outdoors  In case where indoor cables (NYY, NYCY or NYMHY) are used, these cables will not be laid directly into the  ground. They will be passed through pipe or channel. In case where they are bedded into the ground they will  have XLPE insulation, steel wire armoured and extruded PVC covered twisted copper conductor.  For signal cables thin multi-wired electrolytic copper conductor, PVC isolated, core, tinned copper mesh  screened, out coating PVC in indoor environment, and PE in outdoor environment LIYCY cables will be used.  The cores of the signal cables will be numbered and panel outputs will be labelled at the device inputs. Cables shall be provided in five times two pairs, ten times two pairs, twenty times two pairs or thirty times two  pairs, as circuits require.  8.15.2 Signal cables  8.15.3 Lighting cables  8.15.4 Earthing and bonding cables  8.16 Cable Routing  8.16.1 Cable segregation  8.16.2 Cable trays, ladders and trunking  8_Vol3_d4 3_Section 8 electrical works_en_GIR rev6.doc  • Distance between the above mentioned cables must not be less than 200 mm.  • Signal cables.  • Power cables energised by frequency converters.  • Power cables for building services.  • Power cables for technical power.  Throughout installations four continuous separate tracks shall be established for:  Cables operating at different voltages and for different purposes shall be properly segregated. All power and signal cables will be laid in a separate tray.  PVC insulated earthing cables shall comply with IEC 60227 and 60228 and must not be less than 2,5 mm² cross  section with a single stranded copper conductor with an extruded PVC insulation coloured green/yellow in  spiral stripes.  Bare earthing cables shall comply with IEC 60228 and must not be less than 16 mm² stranded copper single  conductor and sized according to the requirements of the IEC 60364. 