F0-2AD2DA-2 2-Ch.
In/2-Ch. Out AnAlOg
Chapter
Chapter
Chapter
VOltAge COmbInAtIOn
In This Chapter...
Module Specifications .............................................................................................12–2
Setting the Module Jumpers ................................................................................... 12–4
Connecting and Disconnecting the Field Wiring ...................................................12–5
Wiring Diagram .......................................................................................................12–5
Module Operation ................................................................................................... 12–6
Special V-memory Locations ...................................................................................12–7
Using the Pointer in Your Control Program ......................................................... 12–10
Scale Conversions .................................................................................................. 12–12
Module Resolution .................................................................................................12–15
Analog Input Ladder Logic Filter ..........................................................................12–16
12
12
12
Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
Module Specifications
The F0-2AD2DA-2 Analog Combination module offers the following features: The analog
input and output channels are updated in one scan.
• The module has a removable terminal block which makes it
possible to remove the module without disconnecting the field
wiring.
• Analog inputs can be used as process variables for the four (4)
PID loops in the DL05 and the eight (8) PID loops in the DL06
CPUs.
• On-board active analog filtering and RISC-like microcontroller
provide digital signal processing to maintain precise analog
measurements in noisy environments.
12–2
NOTE: The DL05 CPU’s analog feature for this module requires DirectSOFT32 Version 3.0c (or later) and
firmware version 3.30 (or later). The DL06 requires DirectSOFT32 version V4.0, build 16 (or later) and
firmware version 1.00 (or later). See our website for more information: www.automationdirect.com.
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
The following tables provide the specifications for the F0–2AD2DA–2 Analog Voltage
Combination Module. Review these specifications to make sure the module meets your
application requirements.
Input Specifications
Number of Channels
Input Range
Resolution
Step Response
Crosstalk
Active Low-pass Filtering
Input Impedance
Absolute Maximum Ratings
Linearity Error (End to End)
Input Stability
Gain Error
Offset Error
Maximum Inaccuracy
Accuracy vs. Temperature
Number of Channels
Output Range
Resolution
Conversion Settling Time
Crosstalk
Peak Output Voltage
Offset Error
Gain Error
Linearity Error (end to end)
Output Stability
Load Impedance
Load Capacitance
Accuracy vs. Temperature
* One count in the specification table is equal to one least significant bit of the analog data value (1 in 4096).
2, single ended (one common)
0 to 5VDC or 0 to 10VDC (jumper selectable)
12 bit (1 in 4096)
10.0 ms to 95% of full step change
1/2 count maximum (-80db)*
-3dB at 300Hz (-12dB per octave)
Greater than 20kq
±15V
±2 counts (0.025% of full scale) maximum*
± 1 count *
± 6 counts *
± 2 counts *
0.3% @ 25°C (77°F)
0.6% 0 to 60°C (32 to 140°F)
±100 ppm/°C typical
Output Specifications
2, single ended (one common)
0 to 5VDC or 0 to 10VDC (jumper selectable)
12 bit (1 in 4096)
50µS for full scale change
1/2 count maximum (-80db) *
±15VDC (power supply limited)
0.1% of range
0.4% of range
±1 count (0.075% of full scale) maximum*
±2 counts*
2kq minimum
0.01 µF maximum
±50 ppm/°C typical
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
12–3
Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
General Specifications
PLC Update Rate
16-bit Data Word
Operating Temperature
Storage Temperature
Relative Humidity
Environmental Air
Vibration
Shock
Noise Immunity
Power Budget Requirement
External Power Supply
Connector
Connector Wire Size
Connector Screw Torque
Connector Screwdriver Size
2 input channels per scan
2 output channels per scan
12 binary data bits
0 to 60° C (32 to 140° F)
-20 to 70° C (-4 to 158° F)
5 to 95% (non-condensing)
No corrosive gases permitted
MIL STD 810C 514.2
MIL STD 810C 516.2
NEMA ICS3-304
50mA @ 5VDC (supplied by base)
30mA, 24VDC ±10%
Phoenix Mecano, Inc. Part No. AK1550/8-3.5 - green
28–16 AWG
3.5 inch-pounds (0.4 N·m)
DN-SS1 (recommended)
Setting the Module Jumpers
The position of the J2 jumpers determines the input and output signal levels. You can choose
between 0–5 VDC or 0–10 VDC. The module ships with the jumpers connecting the pins.
In this position, the input and output signal level is 0–5 VDC. To select 0–10 VDC signals,
use the jumper setting chart located on the module. One or more channels can be selected for
0–10 VDC input and output signal level by removing the jumper from the connecting pins of
the appropriate channel. This will allow you to have one channel selected for a 0–5 VDC signal
and another channel selected for a 0–10 VDC signal.
12–4
J2, jumpers shown below, are
configured as, CH1 INPUT and
CH2 OUTPUT both set for 10V.
CH2 INPUT and CH1 OUTPUT
both set for 5V.
J2 (JUMPERS)
F0–2AD2DA–2
Refer to jumper setting chart.
C20
ON=5V
OUT INPUT
CH2
CH1
CH2
CH1
WARNING: Before removing the analog module or the terminal block on the face of the module,
disconnect power to the PLC and all field devices. Failure to disconnect power can result in damage to
the PLC and/or field devices.
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
Typical User Wiring
Module Supply
Connecting and Disconnecting the Field Wiring
Wiring Guidelines
Your company may have guidelines for wiring and cable installation. If so, you should check
those before you begin the installation. Here are some general things to consider:
• Use the shortest wiring route whenever possible.
• Use shielded wiring and ground the shield at the transmitter source. Do not ground the shield at both
the module and the source.
• Do not run the signal wiring next to large motors, high current switches, or transformers. This may
cause noise problems.
• Route the wiring through an approved cable housing to minimize the risk of accidental damage.
Check local and national codes to choose the correct method for your application.
The F0–2AD2DA–2 will require an external power supply with a rating of 18.0–26.4 VDC at
30mA.
To remove the terminal block, disconnect power to the PLC and the field devices. Pull the
terminal block firmly until the connector separates from the module.
You can remove the analog module from the PLC by folding out the retaining tabs at the top
and bottom of the module. As the retaining tabs pivot upward and outward, the module’s
connector is lifted out of the PLC socket. Once the connector is free, you can lift the module
out of its slot.
Wiring Diagram
Use the following diagram to connect the field wiring. If necessary, the F0–2AD2DA–2 terminal
block can be removed to make removal of the module possible without disturbing field wiring.
See NOTE 1
CH1
4–wire
Voltage
Transmitter
CH2
2–wire
Voltage
Transmitter
CH 1 load
2k ohms
minimum
Resistance
CH 2 load
2k ohms
minimum
Resistance
source.
commons.
+
–
+
–
–
+
NOTE 1: Shields should be grounded at the signal
NOTE 2: Connect all external power supply
Transmitter
Power Supply
+
NOTE: To ensure that readings on unused channels are zero, install
–
a jumper between the CHx and COM terminals on all unused channels.
Internal
Module
Wiring
1
IN
2
0V
18.0–26.4VDC
Power Supply
1
OUT
2
0V
V+
24V
0V
+–
Voltage Source
Voltage Source
OV
Ch 1
Ch 2
Analog Switch
A to D
Converter
D to A
Converter
D to A
Converter
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
Analog
In/Out
2–In/2–Out
0–5V
0–10V
1
IN
2
0V
1
OUT
2
0V
V+
24V
0V
F0–2AD2DA–2
12–5
Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
Module Operation
Input/Output Channel Scanning Sequence
The DL05 and DL06 read two channels of input and two channels of output data during each
scan. The CPU supports special V-memory locations that are used to manage the data transfer.
This is discussed in more detail on the following page, “Special V-memory Locations”.
Scan
Read Inputs
DL05/DL06 PLC
Execute Application Progr
Read the data
Store data
Write to Outputs
am
Scan N
Scan N+1
Scan N+2
Scan N+3
Scan N+4
Ch 1, 2 IN; Ch 1,2 OUT
Ch 1, 2 IN; Ch 1,2 OUT
Ch 1, 2 IN; Ch 1,2 OUT
Ch 1, 2 IN; Ch 1,2 OUT
Ch 1, 2 IN; Ch 1,2 OUT
Analog Module Updates
Even though the channel updates to the CPU are synchronous with the CPU scan, the module
asynchronously monitors the analog transmitter signals and converts each signal into a 12-bit
binary representation. This enables the module to continuously provide accurate measurements
without slowing down the discrete control logic in the RLL program.
The module takes approximately 10 milliseconds to sense 95% of the change in the analog
signal. For the vast majority of applications, the process changes are much slower than these
updates.
NOTE: If you are comparing other manufacturers’ update times (step responses) with ours, please be aware
that some manufacturers refer to the time it takes to convert the analog signal to a digital value. Our analog
to digital conversion takes only a few microseconds. It is the settling time of the filter that is critical in
determining the full update time. Our update time specification includes the filter settling time.
12–6
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
MSB LSB
Special V-memory Locations
Formatting the Module Data
The DL05 and DL06 PLCs have three special V-memory locations assigned to their respective
option slots These V-memory locations allow you to:
• Specify the data format (binary or BCD)
• Specify the number of I/O channels to scan (2 input and 2 output channels for the F0–2AD2DA–2)
• Specify the V-memory locations to store the input data
• Specify the V-memory locations to store the output data
DL05 Data Formatting
The table below shows the special V-memory locations used by the DL05 PLC for the analog
combination modules.
Analog Combination Module
DL05 Special V-memory Locations
Data Type and Number of I/O Channels V7700
Input Storage Pointer V7701
Output Storage Pointer V7702
Structure of V7700
V-memory location 7700 is used for identifying the number of output channels, the number of
input channels and the data type (binary or BCD). The low byte equals the number of output
channels and the high byte equals the number of
input channels. Either a 1 or a 2 will be entered to
select the number of input and output channels to
be used. A zero (0) entered for channel selection
will cause the channel, either input or output, to
be inoperative.
Loading a constant of 202 into V7700 identifies
two input and two output analog channels, and sets the I/O data type to BCD.
Loading a constant of 8282 into V7700 identifies two input and two output analog channels,
and sets the I/O data type to binary.
LOW BYTE
MSB LSB
HIGH BYTE
Structure of V7701
V7701 is a system parameter that points to a V-memory location used for storing analog
input data. The V-memory location loaded in V7701 is an octal number identifying the first
V-memory location for the analog input data. This V-memory location is user selectable. For
example, loading O2000, using the LDA instruction,causes the pointer to write Ch 1’s data
value to V2000 and Ch 2’s data value to V2001.
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
Structure of V7702
V7702 is a system parameter that points to a V-memory location used for storing analog
output data. The V-memory location loaded in V7702 is an octal number identifying the first
V-memory location for the analog output data. This V-memory location is user selectable. For
example, loading O2010, using the LDA instruction, causes the pointer to write Ch 1’s data
value from V2010 and Ch 2’s data value from V2011.
You will find an example program that loads appropriate values to V7700, V7701 and V7702
on page 12–10.
12–8
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
MSB LSB
HIGH BYTE
DL06 Data Formatting
Special V-memory locations are assigned to the four option module slots of the DL06 PLC.
The table below shows these V-memory locations which can be used by the F0–2AD2DA–2.
Analog Combination Module
DL06 Special V-memory Locations
Slot No. 1 2 3 4
Number of Channels V700 V710 V720 V730
Input Pointer V701 V711 V721 V731
Output Pointer V702 V712 V722 V732
Setup Data Type and Number of Channels
V-memory locations 700, 710, 720 and 730 are used for identifying the number of output
channels, the number of input channels and the data type (binary or BCD). The low byte
equals the number of output channels and the high byte equals the number of input channels.
Enter a 1 or 2 to select the number of input and output channels to be used. A zero (0) entered
for channel selection will cause the channel, either input or output, to be inoperative.
For example, with a module installed in slot 1 by
loading a constant of 202 into V700 identifies two
input and two output analog channels, and sets the
I/O data type to BCD.
And, loading a constant of 8282 into V700
identifies two input and two output analog
channels, and sets the I/O data type to binary.
MSB LSB
LOW BYTE
Input Storage Pointer
V-memory locations 701, 711, 721 and 731 are special locations used as a storage pointers
for the analog input data. With the analog module installed in slot 1, the V-memory location
loaded in V701 is an octal number identifying the first user V-memory location to read the
analog input data. This V-memory location is user selectable. For example, loading O2000,
using the LDA instruction, causes the pointer to write Ch 1’s data value to V2000 and Ch 2’s
data value to V2001.
Output Storage Pointer
V-memory locations 702, 712, 722 and 732 are special locations used as storage pointer for the
analog output data. With the analog module installed in slot 1, the V-memory location loaded
in V702 is an octal number identifying the first user V-memory location to write the analog
output data to. This V-memory location is user selectable. For example, loading O2010, using
the LDA instruction, causes the pointer to write Ch 1’s data value from V2010 and Ch 2’s data
value from V2011.
You will find an example program that loads appropriate values to V700, V701 and V702 on
page 12–11.
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
the
data.
Using the Pointer in Your Control Program
DL05 Pointer Method
The DL05 CPU examines the pointer values (the memory locations identified in V7700,
V7701 and V7702) on the first scan only.
The example program below shows how to setup these locations for 2 input channels and 2
output channels. This rung can be placed anywhere in the ladder program or in the initial stage
if you are using stage programming instructions.
This is all that is required to read the analog input data into V-memory locations. Once the
data is in V-memory you can perform mathematical calculations with the data, compare the
data against preset values, and so forth. V2000 and V2010 is used in the example but you can
use any user V-memory location.
SP0
LD
K202
- or -
LD
K8282
OUT
V7700
LDA
O2000
OUT
V7701
LDA
O2010
OUT
V7702
Load a constant that specifies the number of channels to scan and the
data format. The upper byte selects the input data format (i.e. 0=BCD,
8=Binary) and the number of input channels (set to either 1 or 2 for the
F0–2AD2DA–2). The lower byte selects the output data format (i.e.
0=BCD, 8=Binary) and the number of output channels (set to either 1
or 2).
The binary format is used for displaying data on some operator
interface
units. The DL05 PLCs support binary math functions.
Special V-memory location assigned to the option slot contains the data
format and the number of channels to scan.
This loads an octal value for the first V-memory location that will be used
to store the incoming data. For example, the O2000 entered here using
the LDA instruction would designate the following addresses: Ch1 –
V2000, Ch2 – V2001
The octal address (O2000) is stored here. V7701 is assigned to the
option slot and acts as a pointer , which means the CPU will use the
octal value in this location to determine exactly where to store the
incoming
This loads an octal value for the first V-memory location that will be used
to store the output data. For example, the O2010 entered here using the
LDA instruction would designate the following addresses: Ch1 – V2010,
Ch2 – V2011
The octal address (O2010) is stored here. V7702 is assigned to
option slot and acts as a pointer , which means the CPU will use the
octal value in this location to determine exactly where to store the output
data.
12–10
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
F0–2AD2DA–2
LD
SP0
LD
LDA
O2000
OUT
V701
This loads an octal value for the first V-memory location that will be used
to store the incoming data. For example, O2000 entered here using the
LDA instruction would designate the following addresses: Ch1 – V2000,
Ch2 – V2001
The octal address (O2000) is stored here. V701 is assigned to the first
option slot and acts as a pointer, which means the CPU will use the
octal value in this location to determine exactly where to store the incoming
data.
OUT
V700
Special V-memory location assigned to the first option slot contains the
data
format and the number of channels to scan.
Loads a constant that specifies the number of channels to scan and the
data format. The upper byte selects the input data format (i.e. 0=BCD,
8=Binary) and the number of input channels (set to either 1 or 2 for the
F0–2AD2DA–2). The lower byte selects the output data format (i.e.
0=BCD, 8=Binary) and the number of output channels (set to either 1
or 2).
- or -
The binary format can be used for displaying data on some
operator interface units and on the DL06 LCD display. The DL06
PLCs support binary math functions.
LDA
O2010
OUT
V702
This loads an octal value for the first V-memory location that will be used
to store the output data. For example, O2010 entered here using the
LDA instruction would designate the following addresses: Ch1 – V2010,
Ch2 – V2011
The octal address (O2010) is stored here. V702 is assigned to the first
first slot and acts as a pointer , which means the CPU will use the
octal value in this location to determine exactly where to store the output
data.
K202
K8282
DL06 Pointer Method
Use the special V-memory table as a guide to setup the pointer values in the following example
for the DL06. Slot 1 is the left most option slot. The CPU will examine the pointer values at
these locations only after a mode transition, first scan only.
Analog Combination Module
DL06 Special V-memory Locations
Slot No.
Number of Channels
Input Pointer
Output Pointer
The F0–2AD2DA–2 can be installed in any available DL06 option slot. Using the example
program from the previous page, but changing the V-memory addresses, the ladder diagram
below shows how to setup these locations for 2 input channels and 2 output channels with the
module installed in slot1 of the DL06. Use the above table to determine the pointer values if
locating the module in any of the other slot locations. Place this rung anywhere in the ladder
program or in the initial stage if you are using stage programming instructions.
Like the DL05 example, this logic is all that is required to read the analog input data into
V-memory locations. Once the data is in V-memory you can perform mathematical calculations
with the data, compare the data against preset values, and so forth. V2000 and V2010 is used
in the example but you can use any user V-memory location.
1 2 3 4
V700 V710 V720 V730
V701 V711 V721 V731
V702 V712 V722 V732
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
Scale Conversions
Scaling the Input Data
Many applications call for measurements in
engineering units, which can be more meaningful
than raw data. Convert to engineering units using
the formula shown to the right.
Units =A
H = High limit of the engineering
You may have to make adjustments to the
formula depending on the scale you choose for the
engineering units.
L = Low limit of the engineering
A = Analog value (0 – 4095)
For example, if you wanted to measure pressure
(PSI) from 0.0 to 100.0 then you would have to
multiply the analog value by 10 in order to imply a decimal place when you view the value with
the programming software or a handheld programmer. Notice how the calculations differ when
you use the multiplier.
Analog Value of 2024, slightly less than half scale, should yield 49.4 PSI.
Example without multiplier Example with multiplier
Units =A
Units=2024
Units= 49
H – L
4095
100 – 0
+ L
4095
+ 0
Units=10 A
Units=20240
Units=494
H – L
4095
unit range
unit range
100 – 0
4095
+ L
H – L
4095
+ 0
+ L
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
The Conversion Program
The following example shows how you would write the program to perform the engineering
unit conversion from the input data format 0–4095. This example assumes the raw input data
read at V2000 is in BCD format.
Note: this example uses SP1, which is always on. You
could also use an X, C, etc. permissive contact.
SP1
LD
V2000
MUL
K1000
DIV
K4095
OUT
V2100
When SP1 is on, load Ch 1 data to the accumulator.
Multiply the accumulator by 1000 (for the range of 0–1000).
Divide the accumulator by 4095(the module resolution).
Store the result in V2100.
Output Conversion Program
The following example program shows how you would write the program to convert the
engineering unit to the output data format 0–4095. This example assumes you have calculated
or loaded the engineering unit values between 0–1000 in BCD format and stored them
in V2300 and V2301 for channels 1 and 2 respectively. Both the DL05 and DL06 offer
instructions that allow you to perform math operations using BCD format. It is usually easier
to perform any math calculations in BCD and then convert the value to binary before you send
the data to the module.
SP1
SP1
LD
V2300
MUL
K4095
DIV
K1000
OUT
V2010
LD
V2301
MUL
K4095
DIV
K1000
OUT
V2011
The LD instruction loads the engineering units used with channel 1 into
the accumulator. This example assumes the numbers are BCD. Since
SP1 is used, this rung automatically executes on every scan. You could
also use an X, C, etc. permissive contact.
Multiply the accumulator by 4095.
Divide the accumulator by 1000 (this is the maximum value of
V2300).
Store the BCD result in V2010; the V–memory location set up to
send the data to Ch 1 output.
The LD instruction loads the engineering units used with Ch 2 into the
accumulator. This example assumes the numbers are BCD. Since SP1 is
used, this rung automatically executes on every scan. You could also use
an X, C, etc. permissive contact.
Multiply the accumulator by 4095.
Divide the accumulator by 1000 (this is the maximum value of
V2301).
Store the BCD result in V2011; the V–memory location set up to send
the data to Ch 2 output.
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
Analog and Digital Value Conversions
Sometimes it is useful to convert between the signal levels and the digital values. This is
especially helpful during machine startup or troubleshooting. The following table provides
formulas to make this conversion easier.
Range If you know the digital value If you know the analog signal level
0 to 5V
0 to 10V
A =
4095
A =
4095
5D
10D
For example, if you are using the 0–10V range
and you need a 6V signal level, use this formula to
determine the digital value (D) that will be stored
in the V-memory location that contains the data.
D =
5
D =
10
4095
D =
10
4095
D =
10
D = (409.5) (6)D =
(A)
(6V)
4095
4095
(A)
(A)
2457
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
53211 2048
MSB LSB
Module Resolution
Analog Data Bits
The first twelve bits represent the analog data for both inputs and outputs in binary format.
Bit Value BitV
01664
127 128
248 256
389 512
41610 1024
alue
= data bits
Resolution Details
Since the module has 12-bit resolution for both inputs and outputs, the analog signal is either
converted into 4096 counts or a count value will produce a proportional analog output. In
either situation the count range will be from 0–4095 (212). For example, with an output range
of 0 to 10V, send a 0 to get a 0V signal, and send 4095 to get a 10V signal. This is equivalent
to a binary value of 0000 0000 0000 to 1111 1111 1111, or 000 to FFF hexadecimal.
Each count can also be expressed in terms of the signal level by using the following equation:
0 – 10V
10V
0V
0 4095
The following table shows the smallest detectable signal change that will result in one LSB
change in the data or the amount of change in the output signal that each increment of the
count value will produce.
Resolution =
H = high limit of the signal range
L = low limit of the signal range
H – L
4095
01110987654321
Voltage Range Signal Span Divide By
0 to 5V
0 to 10V
Smallest detectable
or Produced Change
5 volts 4095 1.22 mV
10 volts 4095 2.44 mV
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Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
t
Analog Input Ladder Logic Filter
PID Loops / Filtering
Please refer to the “PID Loop Operation” chapter in the DL06 or DL05 User Manual for
information on the built-in PV filter (DL05/06) and the ladder logic filter (DL06 only) shown
below. A filter must be used to smooth the analog input value when auto tuning PID loops to
prevent giving a false indication of loop characteristics.
Smoothing the Input Signal (DL06 only)
The filter logic can also be used in the same way to smooth the analog input signal to help
stabilize PID loop operation or to stabilize the analog input signal value for use with an operator
interface display, etc.
WARNING: The built-in and logic filters are not intended to smooth or filter noise generated by improper
field device wiring or grounding. Small amounts of electrical noise can cause the input signal to bounce
considerably. Proper field device wiring and grounding must be done before attempting to use the filters
to smooth the analog input signal.
Using Binary Data Format
SP1
LD
V2000
OR
BT
Loads the analog signal, which is in binary forma
and has been loaded from V-memory location
V2000, into the accumulator. Contact SP1 is
always on.
Converts the binary value in the accumulator
to a real number.
12–16
Subtracts the real number stored in location
SUBR
V1400
MULR
R0.2
ADDR
V1400
OUTD
V1400
RTOB
OUT
V1402
V1400 from the real number in the accumulator,
and stores the result in the accumulator. V1400
is the designated workspace in this example.
Multiplies the real number in the accumulator by
0.2 (the filter factor), and stores the result in the
accumulator. This is the filtered value. The filter
range is 0.1 to 0.9. Smaller filter factors
increases filtering. (1.0 eliminates filtering).
Adds the real number stored in
location V1400 to the real number
filtered value in the accumulator, and
stores the result in the accumulator.
Copies the value in the accumulator to
location V1400.
Converts the real number in the
accumulator to a binary value, and
stores the result in the accumulator.
Loads the binary number filtered value from
the accumulator into location V1402 to use in
your application or PID loop.
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
Chapter 12: F0-2AD2DA-2 2-Ch. In/2-Ch. Out Analog Voltage Combination
y
NOTE: Be careful not to do a multiple number conversion on a value. For example, if you are using the pointer
method in BCD format to get the analog value, it must be converted to binary (BIN) as shown below. If you
are using the pointer method in Binary format, the conversion to binary (BIN) instruction is not needed.
Using BCD Data Format
SP1
LDD
V2000
BIN
OR
BT
SUBR
V1400
MULR
R0.2
ADDR
V1400
OUTD
V1400
RTOB
Loads the analog signal, which is in BCD format
and has been loaded from V-memory location
V2000, into the accumulator. Contact SP1 is
always on.
Converts a BCD value in the accumulator to
binary.
Converts the binary value in the accumulator
to a real number.
Subtracts the real number stored in location
V1400 from the real number in the accumulator,
and stores the result in the accumulator. V1400
is the designated workspace in this example.
Multiplies the real number in the accumulator b
0.2 (the filter factor), and stores the result in the
accumulator. This is the filtered value. The filter
range is 0.1 to 0.9. Smaller filter factors
increases filtering. (1.0 eliminates filtering).
Adds the real number stored in
location V1400 to the real number
filtered value in the accumulator, and
stores the result in the accumulator.
Copies the value in the accumulator to
location V1400.
Converts the real number in the
accumulator to a binary value, and
stores the result in the accumulator.
BCD
OUTD
V1402
Converts the binary value in the accumulator
to a BCD number. Note: The BCD instruction
is not needed for PID loop PV (loop PV is a
binary number).
Loads the BCD number filtered value from
the accumulator into location V1402 to use in
your application or PID loop.
DL05/06 Option Modules User Manual; 7th Ed. Rev. E
12–17
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