Danfoss VLT 5000 Operating Instructions Manual

Also see for VLT 5000 FLUX: Service manual Operating instructions Operating instructions Operating instructions Operating instructions

Danfoss VLT 5000 Operating Instructions Manual Manual pdf 8 page image

VLT® 5000/ 5000 FLUX/ 6000 HVAC/8000 AQUA PROFIBUSThe PROFIBUS optioncard Bus topologySingle master operation with DP V0- Single master- PLC communicates with telegrams ofconstant length- Fits to time critical requirementsCyclical transmission (PLC)1. Setpoint transmission2. Actual value feedback3. New set points computed4. New set point transmission5. Parameter Read - using PCV channel6. Parameter Write - using PCV channel7. Read parameter description - using PCV channel Features of DP (Distributed Periphery)- Is used by several PLC manufacturers for remoteperipheral I/O communication.- Supports cyclical communication.- SRD (Send Receive Data) service gives fastcyclical exchange of process data betweenmaster and slaves.- Freeze and synchronize function is supported.- Fixed data structure.- Fixed telegramme size.- Occupies I/O memory space in PLC proportionalto the number of slaves employed, which maylimit the number of participants. Additional datarequire additional I/O memory space.DP should be used when fast cyclical process controlis needed. Such a concept would typically callfor single master operation with a limited numberof slave stations. A high number of slaves willincrease the system response time.This could also be the case where controlloops are closed over the bus. As a very fastalternative it is of course possible to close thecontrol loop outside the bus. Rapid Cyclical transmission with PPO using DP Control of the drives during normal operation is oftenvery time critical, but it involves very few data, suchas control commands and speed reference. DP isoptimized for fast cyclical communication.Parameter up-/downloads can be achieved byusing the PCV part of the so-called Parameter -Process data Objects - PPO types 1, 2 or 5, seedrawing in paragraph PPO description.MG.90.G1.02 - VLT is a registered Danfoss trademark 7