High speed counter's pre-defined data tags: preset

unsaint32 · Mar 15, 2014

I am trying to figure out how to use a High speed counter module for an incremental encoder. I don't have the exact model number for the encoder but it is already wired to 1756-HSC's channel 0's A, B, and Z sections. Specifically, I want to know if I understand the following module defined tags correctly;
O.LoadPreset.0
I.WasPreset.1

In my setup the HSC card is in slot 7, so the actual counter position tag is Local:7:I.PresentValue[0]. It is for a stretch wrap roller.

In the program (I didn't write this program), an overtravel Prox triggers Local:7:O.LoadPreset.0. If I understand it correctly, that changes the encoder's Present value to Preset value. In other words, if the Local:7:I.PresentValue[0] was 5 million at one point, and the Local:7:C.Preset[0] was set at 8milion, the Local:7:I.PresentValue[0] changes from 5 milion to 8 million.

Did I get it right?

Another question is, assuming my understanding is right so far, I guess the result of the triggering event above sets the Local:7:I.WasPreset.0 to 1. But after that, what resets the bit?

Thanks.

osmanmom · Mar 15, 2014

i had read the manual and if i not mistake,the instruction as below,

High Speed Counter Module Configuration Tags area,

C.Preset[0] = DINT = Designates the channel 0 preset value. Module begins counting at this value Values range from 0 - 16777214

C.Preset[0] = 8M.

High Speed Counter Module Input Tags area,

I.PresentValue[0] = DINT = Displays the channel 0 count value Values range from 0 - 16777214

I.PresentValue[0] = 5M

If i need to write a new count value e.g 10M this value will go to C.Preset[0] ,

High Speed Counter Module Output Tags

After O.LoadPreset.0 (BOOL) active once.

if i need to reset count value I.PresentValue[0] i need to write ,

High Speed Counter Module Output Tags

O.ResetCounter.0 (BOOL) active once.

High Speed Counter Module Input Tags

if i need to know the count had reset, i read at I.WasReset.0 = (BOOL)

if i need to know the count loaded,i read at I.WasPreset.0 =(BOOL)

jdbrandt · Mar 15, 2014

unsaint32 said:
I am trying to figure out how to use a High speed counter module for an incremental encoder. I don't have the exact model number for the encoder but it is already wired to 1756-HSC's channel 0's A, B, and Z sections. Specifically, I want to know if I understand the following module defined tags correctly;
O.LoadPreset.0
I.WasPreset.1

In my setup the HSC card is in slot 7, so the actual counter position tag is Local:7:I.PresentValue[0]. It is for a stretch wrap roller.

In the program (I didn't write this program), an overtravel Prox triggers Local:7:O.LoadPreset.0. If I understand it correctly, that changes the encoder's Present value to Preset value. In other words, if the Local:7:I.PresentValue[0] was 5 million at one point, and the Local:7:C.Preset[0] was set at 8milion, the Local:7:I.PresentValue[0] changes from 5 milion to 8 million.

Did I get it right?

Another question is, assuming my understanding is right so far, I guess the result of the triggering event above sets the Local:7:I.WasPreset.0 to 1. But after that, what resets the bit?

Thanks.

I remember doing this on a 1769- platform; and what I remember most was the difficulty in manipulating the value coming out of the module. I was foolish in those days, and thought that "large numbers" are best handled by REAL/Float data types...WRONG!
But the one thing that I remember a bit more was that treating a high speed counter like a virtual or real encoder is a bit tricky at the end...when the count rolls over from its max to its minimum. The PLC just can't be fast enough to do it, and , instead, you have essentially two devices working in two different time spheres (like when PLCs and ROBOTs are on a comm loop), and the result is tricky to handle.
Good luck.

unsaint32 · Mar 15, 2014

osmanmom said:
If i need to write a new count value e.g 10M this value will go to C.Preset[0] ,

High Speed Counter Module Output Tags

After O.LoadPreset.0 (BOOL) active once.

So, if my preset value is 10M, and when I activate O.LoadPreset.0 once, I.PresentValue[0] gets the value of 10M. Right?

osmanmom said:
if i need to know the count had reset, i read at I.WasReset.0 = (BOOL)
if i need to know the count loaded,i read at I.WasPreset.0 =(BOOL)

So, these bits stay 1, until it is re-loaded or re-reset? How long these bits stay 1?

osmanmom · Mar 15, 2014

Preset and Present are different word and meanings.

if you not give any command to reset any counter (until max) it will count.

please try edit online for counter Rockwell PLC.

any system you need reset you will give 1 pulse bool.

any system you need to know the status or condition it will give last state.

High speed counter's pre-defined data tags: preset

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