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Hi All

I purchased a new V1210 for a customer and have been developing a chunky bit of code to drive 64 pumps in various modes.

The date time is becoming reset to 1st Jan '06  It also only happens on power cycle, not on reset or when downloading new code.

I've checked all the obvious stuff:

1. Put in a new battery

2. Checked the battery status bit is fine (in fact I've built in a small piece of code that checks it if is set and the plc starts beeping and a battery icon flashes) until the user presesses confrm at which point I do a reset.

Either I hadnt noticed or it has only started happening recently (about a month into development) - I reckon its the first option though; I have just started working on the shcedule bit that triggers on time so ony now am I paying attention to the time.

Any thoughts anyone?

Could I somehow be inadvertently triggering some state that resets the date/time?

Many thanks

 

Mal

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Thoughts entering the brain..........

Unlikely scenario but check......Is the new battery actually OK?  Does the status bit change correctly if you put in a dud/leave out?  Perhaps the system is power cycling without you noticing, and incorrect battery status is a root cause.

Associated with above, what I/Os are you using, and are they all powered/wired correctly, and through fuses etc?  Perhaps an error somewhere is causing a big enough dip to repower everything when certain I/Os activate everything they have.

cheers,

Aus

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Thanks Ausman!

At this stage I have not connected up the output modules - I'm using an expansion port with 4 x IO-TO16, these are powered by a 3.5A 24V supply which is separate to the PLC power supply which I made the same to avoid mistakes.

So key thing here is that the PLC is the only powered unit at this stage.

Yep the battery is good measuring 3.2V (I think.. I'm not in front of it right now). 

I've checked the battery status and watch it drop after a few seconds when I pull the battery out so confident its not there.

As an update, the supplier reckons it might be a fault where the RTC is not being powered by the battery so when the main supply cycles the RTC resets.

I believe all the operands are retaining their values but will do a more formal test on that to be sure. 

In the mean time the supplier is sending a replacement unit and we'll see how that goes.

 

Cheers Mal

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Hi again Mal,

2 hours ago, MalSnaize said:

these are powered by a 3.5A 24V supply which is separate to the PLC power supply which I made the same to avoid mistakes.

As an aside, clarify this please.  Will the modules power up at exactly the same time as the PLC, or are you meaning you now have everything commoned to one supply.  Don't forget recommended commoning of 0V if separate.  Also, depending on what you are running via the transistors, is 3.5A going to have enough headroom running the modules and all 64 points?

2 hours ago, MalSnaize said:

the RTC is not being powered by the battery so when the main supply cycles the RTC resets.

If the values are being retained, this would be a fairly easy thing to check if you can be bothered undoing things a little.  It could simply be a dud solder point on the crucial chip leg. Of course, I'm assuming the 1210 is still using a separate RTC chip on the board!

cheers,

Aus

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Hi Aus thanks for your additional thoughts.

Attached is a very crude diagram of what I've done; note that this config is phase 1 with 2 x 16-port modules.

You'll see that I not planned to common the 0V (though the power supply earths are commoned on the DIN rail.

So what I understand from your comment is that I should common the two power supply 0v lines - is that correct?

 

On the power side of things, I am running solenoid/air process pumps which are rated at 15mA each - I'm quite confident that one 3.5A @24V power supply will handle that load but if I do see any issues I have the second power supply which is currently opnly driving the PLC so plenty of capacity left over - do you agree?

On the point of taking to the PLC with a soldering iron, it's only a couple of months old and there are far handier swordsmen than I who are less likely to poke a hot iron through the screen :-)

cheers Mal

Afeed Schematic sm.png

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Crude diagram?  Hah...it's great.  You should see some of my initial sketches of unusual things before they go to CAD!

Common the lines?   Yes, but I was more talking about the expansions and also how everything needs to power up at exactly the same time as the plc.   I only ever use a single power supply for an entire system, but I know that Joe T routinely earths all his negatives....quote:   "I usually ground the negative of my DC power supplies."  I'm assuming he is talking about multiple supplies, but perhaps not.  Pls chime in Joe, if you think it necessary! Either way,  commoning of the negative is a logical thing to keep volts consistent throughout the system, and if it is commoned onto ground is perhaps even better.  Me being the pernickety person I am, I would also ensure all the different supplies are at exactly the same volts as well, through tweaking their adjusters.

I am intrigued by such a small current for those solenoids.  Sounds like some small pneumatic robot stuff, which I am not into at all.  Are there any specs for their initial draw?  Most solenoid coils draw far more than rated until the core is correctly pulled into position.  Worth checking to ensure your switching capacity/method is ok and durable. 

cheers,

Aus

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:-)

Yep these are small process pumps (https://www.smcpneumatics.com/smcdigitalcat3/docs/processpump/processpump/PB.pdf) which are being used to deliver various liquid feed an treatment into tanks.

I believe the internal works use a solenoid to "flip" a valve which allows air to actuate a diaphagm which delivers the fluid. So in fact air is doing the heavy lifting and the solenoid just triggers the actions so doesnt carry any significant load.

They are quite cool litte pumps with tiny footprint and capacity of up to a litre a minute being dispensed.

 

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Hi Again all - I had the PLC replaced by my supplier and used that. I also wrote a "user friendly" date/time setup just in case.

Just recently I got the PLC back from my cusomer to do some enhancements and I find that in fact the system is still dropping the date time on power-up. Must have been happening for the customer and they havent mentioned it (unless they have never powered off)

So I've now tried new PLC, new batteries - the only thing that remains consistent is my code.

Is it possiblt that somehow I am somehow resettting the PLC date time? Does any one know of a system bit that would do this and I am somehow bouncing it?

Actually as soon as I wrote that I realise that if that is the case it can only be in y initialisation routines - I'll have a look in those but if anyone does come up with an bright thought I'd be really happy!

 

thanks

 

Mal

 

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Thanks Joe I'm on 4.0(19) am trying to update but the wizard tells me I must use COM1 and no matter what physocal USB I use, it shows as connected via COM3.

 

Does this matter?

 

cheers Mal

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They're talking about Port 1 on the PLC, which the USB port on the PLC takes over when you connect a cable.  Your PC has mapped the adapter to its COM 3.

In other words, you're OK.  Go for it.

Joe T. 

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Panic over! (well it was only me panicking !)

954888272_PLCOSUpgraded.PNG.2dfa069a23ee0764208798a89c76c7b8.PNG

 

Thanks for advice Joe - Unfortunately that didnt crack the original nut - I still lose time/date on power off.

Its not a biggie as customer can enter date time via the little interface I wrote bit would be nice if it didnt lose it..

 

Cheers Mal

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Hi Mal, before doing anything else, have you tried an Initialise and Reset?  Try it first with your program in place.  If it doesn't help, try burning an empty program, do an I&R on that, then do it all again after burning your program back in.

Using I&R has cured occasional very odd behaviour on a system for me.  Bits on that shouldn't be, strange MIs.  It seems to mostly be on programs that have had lots of changes implemented over time, and I'm guessing that the "program variation process" doesn't fully clean things up on the plc as one would expect.

If it doesn't help, go for Flex's offer!

cheers, Aus

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Hi Flex, thanks for the offer, unfortunately I am bound by some strict confidentiality agreements so am not allowed to (its a government department and whilst its not a super-secret project, I still have a failry standard govt contract that I signed).

That did trigger another thought that I should try a very simple bit of code and see if it does the same.

 

Ausman, thanks for your ideas too - I'll give those a try if after I've done the dumb-code test I still see the same behaviour

 

We have a great community here!

 

cheers Mal

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Are you using RFC-1305 function for updating time. If it fails in reading network time it will just write 0?

Or you accidental write to system registers for time? You said it's a bulky code.

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Hi MalSnaize
As i see in help SB24 must be cleared by user.
Maybe in project accidentally this bit is ON.
Otherwise Ethernet card has the RTC sinchronizing future. Is it Ethernet card installed to panel?

 

SB24.JPG

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Doing an I&R, or using SB24 should never clear the RTC data, though. 

But I do like the thoughts of Isak and Kratmel re the network card. 

cheers, Aus

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Hi Kratmel - I see that the bit is low and seraching for that SB shows there is no (direct) reference to it - so I suspect that other than my recent attempts as per Ausman's guidance, I dont touch it - nice thought though, 

 

Isakovic, thanks for the suggestion but no, I dont grab network time nor do I have card installed.

 

Cheers Mal

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OK so I've done the reset and initialise (tried both SB300 and SB24) and downloaded the code.

Date is set fine. Try resets and date / time is retained.

If I pull the power then I lose the date/time

Completely baffled..

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Oh I also tried the dumb - literally totally empty app.

Set the date/time which it held.

Cycled the power and date/time gone..

I'd like to say its a battery or hardware problem but I had exactly the same issue with the first 1210 but after replacing the battery I had the unit replaced by the supplier.

Really bizarre!

 

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OK.

First a clarification that seems to be causing confusion.  In asking you to do an Initialize & Reset, this seems to have been interpreted as directly using SB24.  I was actually referring to the available action in Visilogic which is Connection/Communication & OS/2nd tab bottom right.  But however it is done, it shouldn't make a difference.

Did you do the I & R just like I said after each separate download?

I know that this is an insulting question, but have you got the battery in correctly?  And do any MIs that are in use retain their values after power cycle?

Try removing the battery for an hour or more and see what happens after reinsertion and an I & R upon reboot...using the Visilogic button.

cheers, Aus

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