Using The Wall Clock Time In Controllogix

Controllogix control systems our controllogix control systems use a common control engine with a common development environment to provide high performance in an easy to use environment.

Using the wall clock time in controllogix.

Unlike the plc 5 slc 500 and micrologix all of which have a status file to access similar information in a controllogix or compactlogix requires a gsv get system variable or ssv set system variable instruction. Still struggling with defining the tag values and getting the proper response. The controllogix backplane for coordinated system time cst and. In v16 and later this button not only sets the controller s clock to match the pc s date and time but also sets the controller s clock to match the pc s tz and dst settings.

The first step is to find out the current time which you can read from your processor using a gsv instruction. Another section attribute would be for utc. One section would display the current time in our own time zone. Furthermore the controllogix processor will not automatically adjust for daylight savings time.

1756 time module obtains time from various sources and provides time synchronization on other devices by acting as a gateway between different time synchronization methods and standards. We set the clock forward one hour in the spring and back one hour in the fall. This is where the clock update tool can come in handy. Yet another section would display the total number of seconds that have passed since jan 1 1970.

The scan time of the plc will dictate how fast the register. If you are using the ab controllogix platform and want a bit to cycle on and off at a consistent rate you can address one of the bits of the register that represents the clock microseconds. Time synchronization is accomplished by using these methods standards and protocols. Look at the date time tab in the controller properties window.

Tight integration between the programming software controller and i o modules reduces development time and cost at commissioning and during normal operation. Once all the clocks in a control system share a synchronized common understanding of system time events being monitored in the control system for example the controllogix system can be time stamped to a very high degree of accuracy. These sections would be the attributes. All clocks ultimately derive their time from a clock known as the grandmaster clock.

For more information. Imagine a large clock on the wall with different sections. Gsv wallclocktime the register containing the microseconds is the 7th element in the array.