CPU Parameters in PS501 Versions V1.0 and V1.1¶
Selecting “CPU parameters” in the configuration tree opens the configuration window as shown as follows:
The following parameters can be set:
| Parameter | Default value | Value | Meaning |
Auto run / Start of user program when voltage ON see remark 1 |
On | On | If the Flash memory contains a valid project, the project will be loaded into the RAM memory and executed when switching on the controller. |
| Off | If the Flash memory contains a valid project, this project will be loaded into the RAM memory but not executed when switching on the controller. | ||
| Error LED | On | On | The error LED lights up for errors of all classes. |
| Off_by_E4 | Warnings (E4) are not indicated by the error LED. | ||
| Off_by_E3 | Warnings (E4) and light errors (E3) are not indicated by the error LED. | ||
| Check Battery | On | On | The availability of the battery and the battery status are checked. If no battery is available or the battery is empty, a warning (E4) is generated and the LED ERR lights up. |
| Off | The battery is not checked. No warning (E4) is generated. This also applies if a battery is installed but empty! | ||
| Behaviour of outputs in stop | Off in hardware and online | Off in hardware and online | In case of STOP, all outputs at the hardware and in the online display are set to FALSE or 0. |
| Off in hardware and actual state online | In case of STOP, all outputs at the hardware are set to FALSE or 0. The online display indicates the status from the last cycle of the user program. | ||
| Actual state in hardware and online | The status of the last cycle of the user program is kept for the outputs at the hardware and in the online display. | ||
| Stop on error class | No effect | No effect | In case of an error, the user program is not stopped (exception: error classes E1 and E2 always stop the PLC). |
| E1 | In case of a fatal error (E1), the user program is stopped. | ||
| E2 | In case of a fatal or serious error (E1-E2), the user program is stopped. | ||
| E3 | In case of a fatal, serious or light error (E1-E3), the user program is stopped. | ||
| E4 | In case of a fatal, serious or light error (E1-E3) or a warning (E4), the user program is stopped. | ||
| Warmstart on E2 | Off | Off | In case of a fatal error (E2), no warmstart is performed. |
| On | In case of a fatal error (E2), a warmstart is performed automatically. (V1.2.0 and higher) |
Setting the parameters Auto run and MOD using the display/keypad
Loading and running the user program also depends on the setting for the parameter MOD using the display/keypad (in PM57x, PM58x and PM59x). The display/keypad setting always has the higher priority.
The following applies:
| MOD 00: | The user program will be loaded and run according to the setting for the CPU parameter “Auto run” (default setting). |
| MOD 01: | User program will not be loaded/run. |
| MOD 02: | The user program will be loaded and run independent of the setting for the CPU parameter “Auto run”. |
Keeping the “RUN” pushbutton pressed when booting the PLC automatically activates MOD 01, i.e., the user program is not loaded/run. Thus, it is possible to boot the PLC in Stop status. This may be required if, for example, both serial interfaces are set to Modbus and therefore no access with the Control Builder software is possible via the serial interface.
On CPUs PM55x and PM56x, a RUN/STOP switch is designed for the MOD function in AC500 PM571, PM581 and PM591.
If the RUN/STOPswitch is set to STOP mode before the CPU module is powered on, the program in the CPU will not run after the CPU is powered on. The program can only be executed when the switch is set to RUN mode and the program is downloaded on the CPU again.
If the serial interface COM1 or COM2 is set to communication mode in a running program (e.g. Modbus communication), it can be changed back to other mode (e.g. online access to Control Builder software) only by setting the switch to STOP mode.