Tag alias

Abn

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Hi, I'm a little confuse with the following.
I have several of these.
I have a tag (flow transmitter) FIT_100 that has an alias to the Analog input board Local:3:I:Data.1. No problem there, but I have another tag named Flow_100 that has an alias N20[1]. Now FIT_100 and Flow_100 represent the same device. How Flow_100 gets the information from FIT_100?
I can't find in the program how the link FIT_100 with Flow_100.
I have this happening with different tags.
I hope I have explained myself!

Regards
:confused:
 
Check to see if you have an instruction that moves all the channels in Card 3 to N20[0] to N20[7] or something similar. Many of the older PLC5 programs had moves like that to get all the IO into one Integer file that would then be read by the SCADA or HMI.
 
Check to see if you have an instruction that moves all the channels in Card 3 to N20[0] to N20[7] or something similar. Many of the older PLC5 programs had moves like that to get all the IO into one Integer file that would then be read by the SCADA or HMI.


There were no alias tags in the PLC5. In CLX systems, alias tags are created in the database.

Oh, but you're assuming that this is a CLX program that was converted from an older PLC5 program. That's probably correct.
 
Check to see if you have an instruction that moves all the channels in Card 3 to N20[0] to N20[7] or something similar. Many of the older PLC5 programs had moves like that to get all the IO into one Integer file that would then be read by the SCADA or HMI.

What instruction should be? I used the search bar to find the N20 but can't find a move intruction.
 
What instruction should be? I used the search bar to find the N20 but can't find a move intruction.


Use the Cross-Reference tool in the tag database. It will show you all of the "connections" between these tags.
 
What instruction should be? I used the search bar to find the N20 but can't find a move instruction.

MOV would only copy one word. (N20[0])

COP & CPS can have a length of more than one word.

COP/CPS Local:3:data N20[0] LEN 4 would copy to N20[3]
 
MOV would only copy one word. (N20[0])

COP & CPS can have a length of more than one word.

COP/CPS Local:3:data N20[0] LEN 4 would copy to N20[3]


There could also be FAL instructions, MVM, BTD, CPT, any Math instructions, etc.

The cross-reference will find them all.
 
Hi, I'm a little confuse with the following.
I have several of these.
I have a tag (flow transmitter) FIT_100 that has an alias to the Analog input board Local:3:I:Data.1. No problem there, but I have another tag named Flow_100 that has an alias N20[1]. Now FIT_100 and Flow_100 represent the same device. How Flow_100 gets the information from FIT_100?
I can't find in the program how the link FIT_100 with Flow_100.
I have this happening with different tags.
I hope I have explained myself!

Regards
:confused:

You wouldn't need any program logic to make FIT_100 equal Flow_100. Simply create the two alias tags in the database and have both of them reference the Local:3:I:Data.1 base tag. Flow_100 doesn't "get the information from FIT_100". Both alias tags get their information from the base tag.
 
MOV would only copy one word. (N20[0])

COP & CPS can have a length of more than one word.

COP/CPS Local:3:data N20[0] LEN 4 would copy to N20[3]


I found this instruction: Copy File Source LIT_100 ,<P1_AI_1_1.Data[4]>
Dest N20[8] Length 8

The source is a tag that has an alias Array but the tag itself is not an array.
Anyway, I guess copy file would copy the data from P1_AI_1_1.Data[4] to P1_AI_1_1.Data[11] and from N20[8] to N20[15]
 
I found this instruction: Copy File Source LIT_100 ,<P1_AI_1_1.Data[4]>
Dest N20[8] Length 8

The source is a tag that has an alias Array but the tag itself is not an array.
Anyway, I guess copy file would copy the data from P1_AI_1_1.Data[4] to P1_AI_1_1.Data[11] and from N20[8] to N20[15]


Call me pedantic, but ....

"The source is a tag that is an alias for the Array element
P1_AI_1_1.Data[4]. It will inherit the data type of the array element.

Anyway, I guess copy file would copy the data from P1_AI_1_1.Data[4] to P1_AI_1_1.Data[11] to N20[8] to N20[15]"

There'a lot of "to"s in that last statement, and to make it clearer, if I were writing it down for someone else to read, I would use this syntax...

"P1_AI_1_1.Data[4..11] to N20[8..15]"
 
Call me pedantic, but ....

"The source is a tag that is an alias for the Array element
P1_AI_1_1.Data[4]. It will inherit the data type of the array element.

Anyway, I guess copy file would copy the data from P1_AI_1_1.Data[4] to P1_AI_1_1.Data[11] to N20[8] to N20[15]"

There'a lot of "to"s in that last statement, and to make it clearer, if I were writing it down for someone else to read, I would use this syntax...

"P1_AI_1_1.Data[4..11] to N20[8..15]"

Thanks for the grammar lesson.
 

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