by Regardt Voigt | Mar 21, 2018 | FX3U, FX5, GX Developer, GX IEC, GX Works 2, GX Works 3, PLC
Introduction It is sometimes a requirement to run a PLC program for testing without affecting the actual real outputs. There we discribe how this can be carried out on FX PLCs. Design Considerations To be able to run a PLC program in a test mode such that the program...
by Regardt Voigt | Mar 21, 2018 | GX Developer, GX IEC, GX Works 2, PLC, QSeries
Introduction GX Developer programming software allows the user to create more than one program within a single Qn PLC. This can be useful for structuring an application and/or for controlling program flow as each program can be triggered by any of the following...
by Regardt Voigt | Mar 20, 2018 | GX Developer, GX IEC, GX Works 2, GX Works 3, PLC, Q Series, QSeries
Introduction Many programmers know that labels (pointers) are used in program flow control (e.g. jump to label), but they may not know that labels are also used with function blocks. This document aims to explain the use of labels with function blocks and what can be...
by Regardt Voigt | Mar 20, 2018 | GX Developer, GX IEC, GX Works 2, GX Works 3, Medoc, Software
Introduction Equality instructions such as the EQ_E (equals instruction), have an enable input. The normal expectation for this kind of instruction is that if the enable variable is FALSE (OFF, not active or zero), the result of the instruction will also be equal to...
by Regardt Voigt | Mar 17, 2018 | GX Developer, GX IEC, Software, Uncategorized
Introduction The Q-Series PLCs support the facility to FORCE I/O but it is not always clear how to find out what has been forced if a PLC has been left in this state. It is not good practice to leave a LC with forced I/O but it is possible that this could happen. This...
by Regardt Voigt | Mar 16, 2018 | GX Developer, GX IEC, PLC
Introduction It is not well known that in a Q series PLC and automatic allocation of 500 program steps is taken out of the available program memory space to allow room of on-line program changes. Although it is not normally recommended to modify this setting it is...
by Regardt Voigt | Mar 6, 2018 | FX3U, GX Developer, PLC
Introduction All PLC I/O and devices can be commented in GX Developer and down loaded to the PLC however there are a maximum number of characters. When programming an FX PLC with GX Developer it is possible to comment all I/O and devices. These comments can be stored...
by Regardt Voigt | Mar 6, 2018 | GX Developer, Software
Introduction There is sometimes a requirement to take a running project from a PLC and combine it with comments that exist in another project that may be an earlier version of the same application. Design Constraints Typically, when a PLC project is uploaded into GX...
by Regardt Voigt | Mar 1, 2018 | GT Works 3, GX Developer, GX IEC, GX Works 2, PLC, Software
Introduction GX Developer PLC programming software supports several ways of naming a device or I/O address, but by default the software displays the device address or alias but not both at the same time. This post explains how to display the device address, comment...
by Regardt Voigt | Mar 1, 2018 | FX3U, FX5, GOT HMI, GT Designer 3, GT Works 3, GX Developer, GX IEC, GX Works 2, GX Works 3, PLC, QSeries, Software
Introduction All special function modules used as part of a PLC system contain data stored in buffer memory. An example of this would be raw analogue input values from an analogue input module (special function module). Normally this information or data is transferred...
