Danfoss VT2800 Series Design Manual

Contents

VLT ® 2800 SeriesInstallation■ High voltage warningThe voltage of the frequency converteris dangerous whenever the equipment isconnected to mains. Incorrect installationof the motor or frequency converter may causedamage to the equipment, serious injury or death.Comply with the instructions in this manual, as well asnational and local rules and safety regulations.Touching the electrical parts may be fatal - even afterthe equipment has been disconnected from mains:Wait at least 4 minutes for current dissipate.NB!:It is the responsibility of the user or installerto ensure correct earthing and protection inaccordance with national and local standards.■ EarthingComply with the following at installation:• Safety earthing: The drive has a high leakagecurrent and must be earthed properly for safety.Follow all local safety regulations.• High frequency earthing: Keep earthingconnections as short as possible.Connect all earthing systems to ensure the lowestpossible conductor impedance. The lowest possibleconductor impedance is achieved by keeping theconductor as short as possible and by grounding withthe greatest possible surface area. If multiple drivesare installed in a cabinet, the cabinet backplate, whichmust be made of metal, should be used as a jointearth reference plate. The drives must be fitted to thebackplate at the lowest possible impedance.To achieve low impedance, connect the drive to thebackplate with the drive fastening bolts. Removeall paint from the contact points.■ CablesThe control cable and the mains cable should beinstalled separately from motor cables to preventnoise transfer. As a rule a distance of 20 cm issufficient, but it is recommended that the distanceis as great as possible, particularly when cables areinstalled in parallel over large distances.For sensitive signal cables such as telephone or datacables the greatest possible distance is recommended.Please note that the required distance depends on theinstallation and the sensitivity of the signal cables, andthat for this reason exact values cannot be given.When being placed in cable trays, sensitive cablesmay not be placed in the same cable tray as themotor cable. If signal cables run across powercables, this is done at an angle of 90 degrees.Remember that all noise-filled inlet and outlet cablesto a cabinet must be screened/armoured.See also EMC-compliant electrical installation.■ Screened/armoured cablesThe screen must have low HF impedance, which isachieved by a braided screen of copper, aluminium oriron. Screen reinforcement intended for mechanicalprotection, for example, is not suitable for EMC-correctinstallation. See also Use of EMC-correct cables.■ Extra protectionRCD relays, multiple protective earthing or earthingcan be used as extra protection, provided that localsafety regulations are complied with. In the case of anearth fault, a DC content may develop in the faultycurrent. Never use an RCD (ELCB relay), type A, asit is not suitable for DC faulty currents. If RCD relaysare used, local regulations must be complied with.If RCD relays are used, they must be:- Suitable for protecting equipment with a DC contentin the faulty current (3-phase bridge rectifier).- Suitable for a pulse-shaped, brief dischargeon power-up.- Suitable for a high leakage current.N must be connected before L1 for single phase 200V reduced leakage current units (type code R4).■ High voltage testA high voltage test can be performed byshort-circuiting terminals U, V, W, L1, L2 and L3,and applying max. 2160 V DC in 1 sec. betweenthis short-circuit and terminal 95.MG.28.E9.02 - VLT is a registered Danfoss trademark 43