User Guide - Eurotherm Ltda

nanodac RECORDER/CONTROLLER: USER GUIDE4.9.3 Modbus Master Data Configuration (Cont.)EXAMPLE 2 USER DEFINED PARAMETERThis allows the user to enter a Modbus address (decimal) and a data type in order to read the value of a parameterfrom or write a parameter value to the slave. Modbus address and data types must be obtainedfrom the documentation supplied with the slave device. For convenience, this example uses a nanodac asthe slave; table 5.3 of this document providing the required data.Select configuration menuModbus Master.1.DataProgrammerDataDescriptorCh1 PVModbus MasterPV23.6EtherNet/IPStatusSuccessDigital I/OSlave DeviceSlave 2User LinParameter ListUser DefinedCustom MessageModbus Address256ZirconiaFunction CodeRead Input (4)Data TypeREALPriorityMediumFigure 4.9.3b User defined parametersDATA PARAMETERSThis lists all possible configuration fields that might appear, not just those shown in the examples above.Descriptor Up to 20 characters used to describe the current data item (used in the Modbus Masteruser page (Section 3.4.12)).PVThe process value currently being read from the selected slave. Visible only if data itemis not an alarm type. The value must be wired to a virtual channel with ‘Operation’ =‘Copy’ if it is to be trended and/or recorded.Sys Alm status The status (e.g. None, Active) of the data item. Visible only for specific read profiles. Thevalue must be wired to a virtual channel with ‘Operation’ = ‘Copy’ if it is to be trendedand/or recorded.Chan. Alm Status The status of the data item. Visible only for specific read profiles. The value must bewired to a virtual channel with ‘Operation’ = ‘Copy’ if it is to be trended and/or recorded.SetAllows the user to set an on/off value. Visible only for specific write profiles.ModeAllows the user to set an auto/manual value. Visible only for specific write profiles.ValueConfigured or wired value to be sent to the selected slave. This parameter is availableonly with function codes 6 & 16Fall Back Value The value to be sent to the selected slave if the 'Value' parameter is wired and has a statusother than GOOD_PV. This parameter is available only with function codes 6 & 16It is not possible to wire Fall Back Value from another parameter and it can be configuredonly manuallySendA one shot action that sends the data in the 'Value' parameter or the 'Fall Back Value'parameter (depending upon the status of 'Value') to the selected slave. This is classedas an acyclic write and so is available only for function codes 6 & 16. The 'Priority' parametermust be set to 'Acyclic'Page 140HA030554Issue 7 Nov 12