Danfoss VLT FC 103 Operating Instructions Manual

Also see for VLT FC 103: Service guide Installation guide Installation guide Operating guide Installation guide

Contents

Danfoss VLT FC 103 Operating Instructions Manual Manual pdf 55 page image

3.6 Serial CommunicationRS-485 is a 2-wire bus interface compatible with multi-dropnetwork topology, i.e. nodes can be connected as a bus, orvia drop cables from a common trunk line. A total of 32nodes can be connected to 1 network segment.Repeaters divide network segments. Each repeaterfunctions as a node within the segment it is installed in.Each node connected within a given network must have aunique node address across all segments.• Terminate each segment at both ends, usingeither the termination switch (S801) of thefrequency converter or a biased terminationresistor network.• Always use screened twisted pair (STP) cable forbus cabling.• Always follow good common installation practice.Low-impedance ground connection of the screen at everynode is important, including at high frequencies.• Connect a large surface of the screen to ground,for example with a cable clamp or a conductivecable gland. It may be necessary to applypotential-equalizing cables to maintain the sameground potential throughout the network. Partic-ularly in installations with long cables.• To prevent impedance mismatch, always use thesame type of cable throughout the entirenetwork.• When connecting a motor to the frequencyconverter, always use screened motor cable.Cable Screened twisted pair (STP)Impedance 120 ΩMax. cable length [m] 1200 (including drop lines)500 station-to-stationTable 3.9 Cable Information3.7 Optional Equipment3.7.1 Anti-condensation HeaterAn anti-condensation heater can be installed inside thefrequency converter to prevent condensation from forminginside the enclosure when the unit is turned off. Theheater is controlled by customer-supplied 230 V AC. Forbest results, only operate the heater when the unit is notrunning.3.7.2 Mains ShieldThe mains shield is a Lexan cover installed inside theenclosure to provide protection according to BGV A3(former VBG-4) accident-prevention requirements.NOTICEMains shield is only available for IP21/IP54 (NEMA 1/NEMA 12).Installation Operating InstructionsMG16J202 Danfoss A/S © Rev. 05/2014 All rights reserved. 533 3