adccommunitymod (AutomationDirect) asked a question.
Created Date: August 26,2014
Created By: alex.rosa
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I was wondering if anyone out there has ever used a f0-128 co-processor card to perform mathematical operations on temperature brought in by af fo-04thm thermal couple input. I am having trouble reading out the correct numbers when i perform complex math on the readout values. problem background: I am trying to calculate the enthalpy based off of dry and wet bulb temperatures, so that i can further calculate the correct mixing ratio of air to automate a vent to circulate air flow. Anyways the math involved used complex exponential math and i am unable to figure out what operands i need to use in my BASIC program to spit the processed numbers back into my DL06. I have got it working before when using constant values so i suspect that my problems are coming from the fact that i am attempting to perform this math on a double word. :confused: I do not have to much experience with this so bear with me. If anyone has any advice or can point me in the right direction with this i would greatly appreciate it.. i 've been trying to figure out what i 've been doing wrong for a couple weeks and it is very frustrating. This is my program so far 10 REM initialize vars 15 REM WET BULB 20 A1=S06_VB(2000)*.1 25 REM DRY BULB 30 B1=S06_VB(2002)*.1 35 REM ATMOSPHERIC PRESSURE 40 C1=101 45 REM SUB ROUTINES 50 G1=17.2693882*A1 60 H1=A1+237.30 70 I1=G1/H1 80 D1=0.61078*EXP(I1) 90 E1=0.62198*(D1/(C1-D1)) 100 F1=(1.006*B1+E1*(2501+1.775*B1))*10 110 REM SCALING READOUT VALUES 120 X1=E1*1000 140 Z1=D1*100 145 REM READOUT VALUES 150 S06_VR(2022)=X1 //humidity ratio 160 S06_VR(2024)=Z1 //saturation vapor pressure 170 S06_VR(2023)=F1 // enthalpy
Created Date: August 26,2014
Created by: MacS
This line looks like a typo:
170 S06_VR(2023)=F1 // enthalpy
Was this supposed to be V2026?
Each floating point value in the PLC requires 2 V-memory locations so this S06_VR(2023)=F1 will write to V2023 and V2024. However this will conflict with these two writes:
150 S06_VR(2022)=X1 //humidity ratio
>This writes to V2022 and V2023
160 S06_VR(2024)=Z1 //saturation vapor pressure
>This writes to V2024 and V2025
I suggest adding some PRINT statements to the program to verify the intermediate results.
10 REM initialize vars
15 REM WET BULB
20 A1=S06_VB(2000)*.1
REM
22 PRINT1 "Dry Bulb = ",A1
REM
25 REM DRY BULB
30 B1=S06_VB(2002)*.1
REM
32 PRINT1 "Atomosperic Pressure = ",B1
REM
35 REM ATMOSPHERIC PRESSURE
40 C1=101
45 REM SUB ROUTINES
50 G1=17.2693882*A1
60 H1=A1+237.30
70 I1=G1/H1
80 D1=0.61078*EXP(I1)
90 E1=0.62198*(D1/(C1-D1))
100 F1=(1.006*B1+E1*(2501+1.775*B1))*10
REM
102 PRINT1 "Enthalpy = ",F1
REM
110 REM SCALING READOUT VALUES
120 X1=E1*1000
REM
122 PRINT1 "Humidity Ratio = ",X1
REM
140 Z1=D1*100
REM
142 PRINT1 "Saturation Vapor Pressure = ",Z1
REM
145 REM READOUT VALUES
150 S06_VR(2022)=X1 //humidity ratio
160 S06_VR(2024)=Z1 //saturation vapor pressure
170 S06_VR(2023)=F1 // enthalpy
Created Date: August 26,2014
Created by: alex.rosa
I was wondering if anyone out there has ever used a f0-128 co-processor card to perform mathematical operations on temperature brought in by af fo-04thm thermal couple input. I am having trouble reading out the correct numbers when i perform complex math on the readout values.
problem background:
I am trying to calculate the enthalpy based off of dry and wet bulb temperatures, so that i can further calculate the correct mixing ratio of air to automate a vent to circulate air flow. Anyways the math involved used complex exponential math and i am unable to figure out what operands i need to use in my BASIC program to spit the processed numbers back into my DL06. I have got it working before when using constant values so i suspect that my problems are coming from the fact that i am attempting to perform this math on a double word. :confused: I do not have to much experience with this so bear with me.
If anyone has any advice or can point me in the right direction with this i would greatly appreciate it.. i 've been trying to figure out what i 've been doing wrong for a couple weeks and it is very frustrating.
This is my program so far
10 REM initialize vars
15 REM WET BULB
20 A1=S06_VB(2000)*.1
25 REM DRY BULB
30 B1=S06_VB(2002)*.1
35 REM ATMOSPHERIC PRESSURE
40 C1=101
45 REM SUB ROUTINES
50 G1=17.2693882*A1
60 H1=A1+237.30
70 I1=G1/H1
80 D1=0.61078*EXP(I1)
90 E1=0.62198*(D1/(C1-D1))
100 F1=(1.006*B1+E1*(2501+1.775*B1))*10
110 REM SCALING READOUT VALUES
120 X1=E1*1000
140 Z1=D1*100
145 REM READOUT VALUES
150 S06_VR(2022)=X1 //humidity ratio
160 S06_VR(2024)=Z1 //saturation vapor pressure
170 S06_VR(2023)=F1 // enthalpy