I am putting together a system that includes a ML1200, an analog input module, and a PV 300 Micro operator interface. I have defined several PV screens that allow the user to change scaling constants and test limits using numerical entry fields. The tags point to addresses in the floating point file of the ML1200.

This works good, but I have noticed that if I download to the PanelView or if the communication to the PLC is interupted, it reinitializes all of the values in the PLC to the default values of the numeric entry fields (all zeros). When this occurs, I have to download the program to the PLC to restore the values.

Is there a way I can prevent this from happening? If I protect the F8 file, it will prevent the user from changing the values through the panelview screens. I am thinking of making a copy of the F8 file and copying the values back to the F8 file if it contains zeros, but I am hoping there is a better and easier way to protect the values.

Any help would be greatly appreciated!

In Panelbuilder32, open the project, then expand the application settings folder, click on the power up option.

Then look at the control objects presets, I believe the default is "write to controller" on startup. Unselect this and you should be okay.

If you do have "Write to Controller on Startup" check then select "Use last terminal states" instead of "Use terminal presets"

I think this will do it too. I'm really not sure what the difference is

I think the differences come in to play when there is more than one panelview connected to the same PLC.
If there is only one, then it doesn't matter which option you choose.

As an example, you have two panelviews connected to the same plc, you take panelview 1 off line, while you are off line, an operator uses panelview 2 to make a process change. When panelview 1 comes back on line it will write the value stored in its memory, and the change made by panelview 2 will be lost.

I changed the PV configuration by unchecking the "write to controller on startup" option. This seemed to work. Thanks!

However, I have discovered another issue that has me scratching my head. If I have a power outage, the processor faults when the power is restored. In the processor status file, I see the following error:

"Startup protection after power loss. Error condition exists at power up when bit S1/9 is set and power down occured while running"

Is this a setting that I can change? I want the processor to restart and run when the power is restored.

I figured out the powerup issue. I changed the value of bit S1/9 (startup protection) to "0". The factory default was "1" or on.

Yes, I would set that bit to zero. Goto the S2 data file and select a radix of binary. This will be the easiest way to find it

Ok that makes sense. It has never cause a problem with my appications since they only have one Panelview

Thanks for the tip

So TW how would you feel about 120 panelviews connected to one ControlLogix PLC. Yes, I had one project that crazy.

That would be tough coordination no matter how you did it. What were you doing?

Packing Operator Call Stations to summon a Fork Lift Operator throughout a warehouse. Each Packing Operator had a XYCOM equivalent of a PV to summon a Fork Lift and see how long the system estimated until he would be serviced. System included 120 ethernet XYCOM units, 1 Controllogix with 4 ethernet cards and several routers and etc.

Wow. We looked at doing that on a much smaller scale. Did it work well communicating to that many Panelviews?

I did not do the final install debug. I did the design and initial programming. I had asked for six enet cards and got second guessed by the customers "expert" that one would be enough, but he'd acquiesce and allow for two. And yes it finally took four to get all 120 communicating. That nasty thing about bandwidth and connection count.

Yikes! I thought I had issues to resolve.

Not much of an expert if he thought 2 ENBTs would handle 120 Panelviews. He must have just read the 64 TCP/IP connections and done the math