Using The Wall Clock Time In Controllogix

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.

Using the wall clock time in controllogix. All clocks ultimately derive their time from a clock known as the grandmaster clock. 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. This is where the clock update tool can come in handy. Look at the date time tab in the controller properties window.

Needed something like this to transfer system time to an rsview register for an event time stamp. Still struggling with defining the tag values and getting the proper response. The first step is to find out the current time which you can read from your processor using a gsv instruction. 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.

Gsv wallclocktime the register containing the microseconds is the 7th element in the array. Yet another section would display the total number of seconds that have passed since jan 1 1970. 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. Imagine a large clock on the wall with different sections.

Tight integration between the programming software controller and i o modules reduces development time and cost at commissioning and during normal operation. Furthermore the controllogix processor will not automatically adjust for daylight savings time. For more information. Another section attribute would be for utc.

However many programmers began to enable the tz and dst settings inadvertently when using the set time button in controller properties. 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. Time synchronization is accomplished by using these methods standards and protocols. The controllogix backplane for coordinated system time cst and.

The scan time of the plc will dictate how fast the register. One section would display the current time in our own time zone. 12 thoughts on reading the controllogix system time in ladder logic steve august 18 2010 at 10 43 pm.