Time/Date Synchronization between PV+'s

Hi guys, Happy Thanksgiving!

I've never tried to do this, but I thought it would be handy to know how to do, if possible.
I've used the global connections for sending the PV+ time to a PLC, but what about if you have 2 or more screens running on the same machine? On other projects, I've only got one screen running the global connection time to the PLC, the other screens just do their own thing. Is there a way to make one PV+ the "master" and the other terminals the "slaves"?

Thanks in advance.

Cheers,
Dustin

You can set one panelview to write to the PLC and the others to read using the remote tags. Any time the "Remote Date and Time" tag goes from zero to a non zero value it sets the clock with the "Remote Year", "Remote Month" etc. We synch our panelviews once a day using this.

Why not use the PLCs clock as the master ?

The PVs can all read the same date for display and to set the PV clock.

All the PVs can have the screen that writes a new date/time to the PLC. once they all read it back, they are all synchronised to the new time.

Thanks for the replies. I'll play around with this tomorrow, see if I can get it to work. To have the PV+ "read" the date/time, do you have to use a different set of Global Connection tags than the ones for "writing" the date/time?

dmfrey said:

You can set one panelview to write to the PLC and the others to read using the remote tags. Any time the "Remote Date and Time" tag goes from zero to a non zero value it sets the clock with the "Remote Year", "Remote Month" etc. We synch our panelviews once a day using this.

Click to expand...

Well, I guess if I had read a little more carefully, I would have seen that dmfrey answered my question before I asked it .

I set this up on a piece of packaging equipment this morning that uses two PV+ 1000's on either side of the machine, "operator side" and "drive side". The way I did it, the "operator side" PV+ writes its system time to PLC N registers every 60 seconds, which in turn write via MOV's to the PLC internal S registes for date/time.
I setup the "Remote Date and Time" tag to go high twice per day (at shift changes) which writes the PLC S registers to the Remote Hour, Minute, etc connections in the PV+. Looks like it's going to work just fine.

daba said:

Why not use the PLCs clock as the master ?

Click to expand...

The tech's prefer to change time on the PV+ config screen, rather than have to go online with the PLC and do it there. I only set it up to have the "operator side" terminal be able to write to the PLC, because I figured if the other terminal had a different time, then you would have two conflicting sets of values trying to write to the same N registers on the PLC. I guess after one shift change, the two screens would be synchronized, but I wasn't sure what kind of results I would have before that happened.
Is there a way to have multiple terminals write the time to the Global Connections, but only when the time is actually CHANGED on the terminal, similar to the "Remote Date and Time" connection?

To get around the global tags constantly writing the plc you could create your own clock setting screen in the application instead of using the config screen, then you could trigger the synchronization immediately with the change. If your system is permanently connected on a network to a computer, there is a free tool on Rockwell's site called the Logix 5000 Clock Update Tool (supports plc 5 and slc's too) that can keep the processor clock updated from the computer.

dmfrey said:

To get around the global tags constantly writing the plc you could create your own clock setting screen in the application instead of using the config screen, then you could trigger the synchronization immediately with the change. If your system is permanently connected on a network to a computer, there is a free tool on Rockwell's site called the Logix 5000 Clock Update Tool (supports plc 5 and slc's too) that can keep the processor clock updated from the computer.

Click to expand...

I ended up going with the roll-yer-own time/date screen. That saves resources on the panelview and it saves techs from having to stop the application to change the date/time. And it synched everything up nicely.

Thanks again for the help!

Cheers,
Dustin

bmacattack33

I ended up going with the roll-yer-own time/date screen.

Click to expand...

Can you post\send a screen shot of your screen? I am trying to build one, but can't seem to come up with a logical entry screen for the time elements.

Thanks!

bigyeti4 said:

bmacattack33



Can you post\send a screen shot of your screen? I am trying to build one, but can't seem to come up with a logical entry screen for the time elements.

Thanks!

Click to expand...

Hi and welcome to the forum!
I'd be happy to post a screen-shot, but I won't have access to the development PC until Monday (I'm enjoying a rare three-day weekend at the moment ) I could send you the .mer file to you at that point or just post a screen-shot if you still need it, but I don't think that should be necessary...

The idea for the screen is really pretty simple. It's just a simple screen with a time/date display at the top and six Numeric Input Buttons towards the bottom. One for Clock Hour, Minute, Second, Month, Day, and Year. Let's say an operator clicks the "Set Clock Hour" button, and then puts in "15" and hits enter. That value, "15" is sent to an analog tag associated with the "Value" connection of the object. This tag is addressed to an "N" register on the PLC. After a pre-set delay time in object properties (default I believe is 400 msecs) the decimal tag associated with the "enter" connection on the object goes high for the pre-set hold time (in this case, I think the default is 500 msecs). The "enter" tag is addressed to the "B" file at the bit level.

In the attached example program, the Clock Hour Value tag is assigned to N7:0, while the Enter tag is assigned to B3:0/0. The delay gives time for the PV+ to communicate the Clock Hour Holding Register value change to the PLC before the Enter tag moves the Holding Register value to the System Clock Hour value (S:40).

The next step is to set the "Remote Date/Time Update" tag bit. You will have to assign this tag to the Remote Date/Time Update connection in the Global Connections editor. You will also have to assign the PLC system clock tags (not the holding registers) to the appropriate "Remote Hour", "Remote Minute", etc. connections. In this way, every time a clock component value is changed/updated on the PV+, this request is sent to the PLC, acknowledged and processed, then sent back to each PV+ on the network, so everybody's got the same time.

If you have any more questions, don't hesitate to ask.
Hope this helps, and good luck!

Cheers,
Dustin

This is perfect. I would really appreciate a copy of the .mer. I was having issues with getting the sync to work properly, but this code really helped to make it clear (for me, more than the PV). I was trying to use an independent "apply" button, and having mixed results. The use of the enter tag on the existing controls is great.

Thanks again for your help.

bigyeti4 said:

This is perfect. I would really appreciate a copy of the .mer. I was having issues with getting the sync to work properly, but this code really helped to make it clear (for me, more than the PV). I was trying to use an independent "apply" button, and having mixed results. The use of the enter tag on the existing controls is great.

Thanks again for your help.

Click to expand...

Good, glad to hear my explanation of the logic was helpful. Usually my explanations turn clear water muddy in a hurry.
Send me a pm with your email address and I will send you the .mer and the accompanying .rss for your reference.

Happy to help.

Cheers,
Dustin

Hey all. I realize I'm a little late to this party but I'm trying to set the system time on the PV to match with the time I've got in the PLC. I'm using a Panelview 1250 and a compactlogix L36 processor.

The reason for this is the alarm history (and all the time date displays on the many screens in this program) always looks at the internal clock. I can't seem to be able to change that in spite of reading the currenttime[#] tag I have set up through a GSV instruction in the PLC.

Any thoughts would be appreciated.

Thanks in advance.

Geoff

geofftheelectrician said:

Hey all. I realize I'm a little late to this party but I'm trying to set the system time on the PV to match with the time I've got in the PLC. I'm using a Panelview 1250 and a compactlogix L36 processor.

The reason for this is the alarm history (and all the time date displays on the many screens in this program) always looks at the internal clock. I can't seem to be able to change that in spite of reading the currenttime[#] tag I have set up through a GSV instruction in the PLC.

Any thoughts would be appreciated.

Thanks in advance.

Geoff

Click to expand...

Welcome to the forum!
Do you have the PV setup to read the PLC system time tags in the Global Connections of the PV+ application? You also need a BOOL tag that the PLC sets high (Or have the PV+ do it through use of a momentary button) assigned in the "Remote Date and Time" connection to get the PV+ to actually update to the PLC time registers.

In my application shown here, I actually just automatically set the "RemoteUpdate_HMI_Time" bit high once an hour to keep everything synced up.

This how I setup mine, I sync my programming pc daily with nettime 3.14 and sync the plcs once a day with rockwell clock sync tool and its been working flawless for 2 years now.

Thanks guys.

I did set up the Global Connections remote date and time in the PV to read the currenttime DINT I had set up through my GSV. I was just trying to do some testing to see how it would work and was toggling a test bit on and off to enable the GSV instruction.

I was able to read the time and date in numeric and string displays but it was having no effect on the system time in the PV, which is displayed on almost every screen.

Do you suppose the PV firmware being 5.10 could be a contributing factor?

How does your logic to generate the update affect the curent time? I'm reading this on my phone as I had to leave work for an eye doctors app so I may have missed something. I will look further at it tomorrow when I'm in.

Appreciate your help.