Reading flow on a 24hr period

[diat150]

Yes, it is a totalflow
But it does not monitor from 10:00 to 10:00
The meter is setup to go from 12:00 to 12:00

So I'm assuming it resets at 12:00 each day

I need to start monitoring the flow from 10:00 to 10:00
& reset it at 10:00 am in Wonderware each morning

Thanks

you need to change the contract hour in the totalflow. you can dwnload the software to connect to the totalflow from their website. you will need a special cable unless it is hooked to ethernet.

 

[AshleyParr]

OK i think theres a few things that were required at the start so we could help you that now make this a different situation.

You said it was instant flow at the start, in a post later on you say this totalizes the flow then resets at 12.

So scrap the scripts i said before, they are for if you were looking at the instant flow. I think you either need to change the time on the instrument or do some messy scripting & maths.

Step 1, Record the total at the start of your log
currentTime is 10:00:00,

startTotal = TotalFlow

Step 2, Record the total before the totalizer resets
currentTime is 11:59:59,

midTotal = TotalFlow

Step 3, Record the total before the your self built totalizer resets
currentTime is 09:59:59,

endTotal = TotalFlow
flowDayTotal = (midTotal-startTotal)+endTotal

And that should do it, you take the value accumulated before the reset & store it to a tag. Then before the next day(10am) read the accumulated total & to the previous value & you have your 24hr total, 10-10.

Hope that makes sense,
Ash

P.S. I was planning on replying, i didnt need a message too

 

[Ones_Zeros]

Hello AshleyParr,

Sorry for the confusion, i apologize for that
I don't mess with the totalflow meters alot, we have a group that does this

i sent you a message also but wanted to post here as well.

thank you for the scripting, I will give this a shot. so I would put all this scripting in a data change script in Wonderware?

also
I may try to get this totalflow ran into a PLC input
then
I can use the first code you posted

but i had a question on line 2 of this script

FlowIncrement = FlowRate/60
FlowTotal = FlowTotal+FlowIncrement

I understand the first line is taking the totalflow rate/60, gets this total into hours.
but
What are you referring to as "Flowtotal" on line 2 of the script (flowtotal + flowincrement)

after us talking I think the simplest solution would be for me to try to get this totalflow meter ran into a PLC input. so i can use the first code you gave me.

again i appreciate your help & patience with me on this issue. if you dont mind please could you explain the script above, just so i fully i understand



thanks

 

[diat150]

after us talking I think the simplest solution would be for me to try to get this totalflow meter ran into a PLC input. so i can use the first code you gave me.

why would you say that? all you need to do is change the contract hour on the totalflow. you are going to cause yourself trouble because your reading will not be the same or as accurate as the totalflow. it is a product designed to accumulate totals.

if you are against changing the contract hour, your best bet would be to use the total accumalted volume from the totalflow. you could read this number at 10 am everyday and subtract the previous days reading at 10 am and get the exact amount of volume that passed thru the meter for the last 24 hours. that would be a really accurate representation, much more accurate than any calculation you do in the plc or wonderware.

 

[Ones_Zeros]

Hello diat150,
thanks for the reply
I will ask someone in that dept to change the "contract hour" on the totalflow meter.

if this is somehow again policy to change this

I would still need to use scripting in wonderware to read the
"c_accum_vol" from the totalflow meter?

so how would I script this into wonderware to perform this action?

you could read this number at 10 am everyday and subtract the previous days reading at 10 am and get the exact amount of volume that passed thru the meter for the last 24 hours.

thank you guys so much for your help and patience with me

 

[diat150]

that number is a total running volume on the meter. so all you need to do is grab that number at 10 everyday, then subtract todays 10 am reading from yesterdays 10am reading and that will be the total volume for the 24 hour period.

 

[AshleyParr]

that number is a total running volume on the meter. so all you need to do is grab that number at 10 everyday, then subtract todays 10 am reading from yesterdays 10am reading and that will be the total volume for the 24 hour period.

He said the total resets at 12, so grabbing the value at 10 each day will not accurately show the usage.

 

[AshleyParr]

thank you for the scripting, I will give this a shot. so I would put all this scripting in a data change script in Wonderware?

Conditional scripts as you need to be checking the time for it to run. Probably easiest way to do this without changing the instrument.

I'm just nipping out but will explain the code I posted later

Ash

 

[diat150]

He said the total resets at 12, so grabbing the value at 10 each day will not accurately show the usage.

sorry, you are wrong. the totalflow makes a total accumulated volume register available, which is just an accumulated volume from the time the meter was first installed. this isnt rolled over everyday like the todays accumulated volume register.

Ive polled probably 5000 of these meters. I am an expert on them.

 

[AshleyParr]

sorry, you are wrong. the totalflow makes a total accumulated volume register available, which is just an accumulated volume from the time the meter was first installed. this isnt rolled over everyday like the todays accumulated volume register.

Ive polled probably 5000 of these meters. I am an expert on them.

Sound, my applogies

 

[NetNathan]

Discussed here also...
http://www.plctalk.net/qanda/showthread.php?t=103852

 

[Ones_Zeros]

Hello,
should line 2 of this script be

FlowIncrement = FlowRate/60
FlowTotal = FlowTotal+FlowIncrement (FlowTotal = FlowRate+FlowIncrement) ????


confused about this line
thanks

Code:
FlowIncrement = FlowRate/60
FlowTotal = FlowTotal+FlowIncrement

Now you need to do this in InTouch, messy & program intensive which is why I was suggesting the Plc.
Start off by sampling every second, data change script using $Second and use the code above.

Code:
Condition Script when $Hour ==10 AND $Mintute==0 AND $Second==0, THEN
FlowIncrement = 0
FlowTotal = 0

 

[AshleyParr]

should line 2 of this script be

FlowIncrement = FlowRate/60
FlowTotal = FlowTotal+FlowIncrement (FlowTotal = FlowRate+FlowIncrement) ????


confused about this line
thanks

No it should be FlowTotal = FlowTotal+FlowIncrement so then it adds the increment to its self.

This would be used if you have an INSTANT flow rate, as you have a totalizer then this is no longer required.

As one of the other guys mentioned with more experience, if its the acuumulated value just calculate using that

 

[Ones_Zeros]

Ok thanks if I can get the flow working through a PLC
Then I will try the continuous flow

But what are you referring to "flowtotal" & "flow rate"

What are these values??

I'm confused on the two

 

[Ones_Zeros]

So is "Flowrate" the totalflow value
from the totalflow meter?

& what is "FlowTotal" what is this tag referring to?

Please explain, I'm working on getting a 4-20 ma signal
Into a PLC so if I can get some understanding of these
Tags in this script, I will be able to use it in Wonderware.


Thanks