Analog F2-08DA-2 User Manual

F2-08DA-2, 8-ChAnnel AnAlog VoltAge output

In This Chapter...

Module Speciﬁcations ............................................................................................. 11-2

Setting the Module Jumpers ................................................................................... 11-5

Connecting the Field Wiring ................................................................................... 11-6

Module Operation ................................................................................................... 11-8

Writing the Control Program ................................................................................ 11-12

Chapter

Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Module Speciﬁcations

The F2-08DA-2 Analog Output module provides several hardware features:

• Analog outputs are optically isolated from the PLC logic.

• The module has a removable terminal block so the module can be easily removed or changed without disconnecting the wiring.

• All channels can be updated in one scan if either a D2-240, a D2-250-1, a D2-260 or a D2-262 CPU is used in the PLC.

• Outputs are voltage sourcing.

• Outputs can be conﬁgured for either of the following ranges:

1. 0–5 VDC

2. 0–10 VDC

Firmware Requirements:

• To use this module, D2-230 CPUs must have ﬁrmware version 2.7 or later.

• To use the pointer method for writing values, D2-240 CPUs require ﬁrmware version 3.0 or later.

• D2-250-1, D2-260, and D2-262 CPUs require ﬁrmware version 1.33 or later.

OUT ANALOG

F2-08DA-2

18-30VDC 80mA ANALOG OUT 0-5VDC 0-10VDC

+24V

+V1

+V2

+V3

+V4

+V5

+V6

+V7

+V8

F2-08DA-2

8CH

F2-08DA-2

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

The following tables provide the specifications for the F2–08DA –2 Analog Output Module. Review these specifications to make sure the module meets your application requirements.

Output Specifications

Number of Channels Output Range Resolution Output Type Peak Output Voltage Load Impedance Load Capacitance Linearity Error (end to end)

Conversion Settling Time

Full-scale Calibration Error (offset error included)

Offset Calibration Error

Maximum Inaccuracy

Accuracy vs. Temperature

PLC Update Rate

Digital Outputs / Output Points Required

Power Budget Requirement External Power Supply Operating Temperature Storage Temperature Relative Humidity Environmental Air Vibration Shock Noise Immunity

8, single-ended 0–5 V, 0–10 V 12 bit (1 in 4096) Voltage sourcing 15VDC (clamped by transient voltage suppressor) 1kq (0–5 V range); 10kq (0–10 V range)

0.01 µF maximum ± 1 count (± 0.025% of full scale) maximum 400µs maximum (full scale change)

4.5 – 9.0 ms for digital out to analog out

± 12 counts maximum, @ 25°C (77°F)

± 3 counts maximum, @ 25°C (77°F) ± 0.3% @ 25°C (77°F)

± 0.45% 0–60°C (32–140°F) ± 57ppm/°C full scale calibration change

(Including maximum offset change of 2 counts)

General Specifications

1 channel per scan maximum (multiplexing) 8 channels per scan maximum (pointer –

D2-240/D2-250-1/D2-260 and D2-262 only)

12 binary data bits, 3 channel ID bits, 1 output enable bit; 16 (Y) output points required

60mA @ 5VDC (supplied by the base) 24VDC(± 10%), 140mA (outputs fully loaded) 0–60°C (32–140°F)

-20°C to 70°C (-4°F to 158°F) 5–95% (non-condensing) No corrosive gases permitted MIL STD 810C 514.2 MIL STD 810C 516.2 NEMA ICS3-304

Analog Output Conﬁguration Requirements

The F2-08DA-2 analog output module requires 16 discrete output points. The module can be installed in any slot of a DL205 PLC, but the available power budget and discrete I/O points are the limiting factors. Check the DL205 PLC User Manual for the particular model of CPU and I/O base being used for information regarding power budget and number of local base, local expansion base or remote I/O points.

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

16pt

Input

8pt

Input

8pt

Output Output

16pt

Output

X17

X20

X27

Y17

Y20

Y27

Y30

Y47

F2-08DA--2

Incorrect

Slot 0Slot 1Slot 2Slot 3Slot4

Special Placement Requirements (D2-230 and Remote I/O Bases)

It is important to examine the configuration if a D2-230 CPU is being used. As can be seen in the section on Writing the Control Program, V-memory locations are used to hold the analog data that will be written to the output. If the module is placed in a slot so that the output points do not start on a V-memory boundary, the program instructions aren’t able to access the data. This also applies when placing this module in a remote base using a D2-RSSS in the CPU slot.

Correct!

F2-08DA-2

Slot 0Slot 1Slot 2Slot 3Slot4

16pt

8pt

Input

X20

X17

X27

16pt

Output

Y17

16pt

8pt

Output Output

Y20

Y40

Y37

Y47

V40500V40502

Data can be written correctly because the output points start on a V-memory boundary address as seen this table.

Incorrect

Slot 0Slot 1Slot 2Slot 3Slot4

16pt

Input

X17

Y 3 7

8pt

Input

X20

X27

16pt

Output

Y17

V40501

F2-08DA--2

8pt

Output Output

Y20

Y27

16pt

Y30

Y47

BSLBSM

Y 2 0

Data is split over three locations, so instructions cannot access data from a D2-230 (or when the module is placed in a remote base).

V40502

BSLBSM

V40501

BSLBSM

11-4

Y 2 0

Y 5 7

To use the V-memory references required for a D2-230 CPU, the ﬁrst output address assigned to the module must be one of the following Y locations. The table also shows the V-memory addresses that correspond to these Y locations.

Y0 Y20 Y40 Y60 Y100 Y120 Y140

V40500 V40501 V40502 V40503 V40504 V40505 V40506 V40507

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

0V -- 5V 0V -- 10V

4095040950

NOTICE: F2-08DA-2 Jumper locations have changed per diagram.

Setting the Module Jumpers

The F2-08DA-2 Analog Output module uses a jumper for selecting the voltage ranges of 0–5 V or 0–10 V.

This ﬁgure shows the jumper locations. See the table on the following page to determine the proper settings for your application.

0–10V

Old Jumper Locations

Jumper Location

Revision A5 and Lower

0–10V

Jumpe Location

New Jumper Locations

Revision B and Higher

Voltage Range and Output Combinations

The table lists both possible combinations of voltage ranges and data formats, along with the corresponding jumper settings.

Voltage Range Output Data Format

0–5V 0–4095 Install

0–10V 0–4095 Remove

Jumper Setting

(top board)

The following graphs show the voltage range to output data format relationship for each of the two selections.

Ranges

10V

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Connecting the Field Wiring

Wiring Guidelines

Your company may have guidelines for wiring and cable installation. If so, check the guidelines before beginning 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.

User Power Supply Requirements

The F2-08DA-2 module requires at least one field-side power supply. The same or separate power sources can be used for the module supply and the voltage transmitter supply. The F2-08DA-2 module requires 21.6-26.4 VDC (at 140 mA), from the external power supply.

The DL205 AC bases have a built-in 24VDC power supply that provide up to 300 mA of current. This can be used instead of a separate supply. Check the power budget to be safe.

It is desirable in some situations to power the transmitters separately in a location remote from the PLC. This will work as long as the transmitter supply meets the current requirements, and the transmitter’s minus (-) side and the module supply’s minus (-) side are connected together.

11-6

WARNING: If the internal 24VDC base power is used, be sure to calculate the power budget. Exceeding the power budget can cause unpredictable system operation that can lead to a risk of personal injury or equipment damage.

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Wiring Diagram

The F2-08DA-2 module has a removable connector which helps to simplify wiring. Squeeze the top and bottom retaining clips and gently pull the connector from the module. Use the following diagram to connect the ﬁeld wiring.

Internal Module

Wiring

Converte r

DC to DC

Ch 1

Voltage source

Ch 8

Voltage source

Converte r

Ch 1 load

1K--10K ohms

minimum

Ch 8 load

1K--10K ohms

minimum

S ee

NOTE 1

S ee

NOTE 1

21.6

- 26.4 VDC

@ 14 0mA

+ --

0VDC

+24VDC

+V1

+V2

+V3

+V4

+V5

+V6

+V7

+V8

NOTE 1: Shields should be connected to the 0V terminal of the module or 0V of the power supply.

+5V

+15V

--15V

D to A

Converte r

OUT ANALOG

F2-08DA-2

18-30VDC 80mA ANALOG OUT 0-5VDC 0-10VDC

+24V

+V1

+V2

+V3

+V4

+V5

+V6

+V7

+V8

F2-08DA-2

8CH

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Module Operation

Before beginning to write the control program, it is important to take a few minutes to understand how the module processes the analog signals.

Channel Update Sequence (Multiplexing) for a D2-230 CPU

If a multiplexing program is being used, only one channel of data can be sent to the output module on each scan. The module refreshes both ﬁeld devices on each scan, but new data can only be obtained from the CPU at the rate of one channel per scan. Since there are eight channels, it can take eight scans to update all channels. However, if only one channel is being used, that channel will be updated on every scan. The multiplexing method can also be used for the D2-240, D2-250-1, D2-260 and D2-262 CPUs.

Scan

Read inputs

System Using

Multiplex

Method

(D2-230)

11-8

ExecuteApplicationProgram

Calculatethe data

Writedata

Writeto outputs

DL205 Analog I/O Manual, 7th Edition, Rev. G

Scan N

Scan N+1

Scan N+2

Scan N+3

. . .

Scan N+8

Channel 1

Channel 2

Channel 3

Channel 4

. . .

Channel 8

Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Channel Update Sequence (Pointer Method) for D2-240, D2-250-1, D2-260 and D2-262 CPUs

If either a D2-240, D2-250-1, D2-260 or a D2-262 CPU is used with the pointer method, all channels can be updated on every scan. This is because the three CPUs support special V-memory locations that are used to manage the data transfer. This is discussed in more detail in the section on Writing the Control Program later in this chapter.

System With

Scan

Read inputs

D2-240, D2-250-- 1

D2-260 or D2-262 CPU

Using Pointer Method

ExecuteApplicationProgram

Calculatethe data

Writedata

Writeto outputs

Scan N

Scan N+1

Scan N+2

Scan N+3

Scan N+4

Channel1,2...8

Channel 1, 2...8

Channel1,2...8

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Understanding the Output Assignments

Remember that the F2-08DA-2 module appears to the CPU as a 16-point discrete output module. These points provide the data value and an indication of which channel to update. Note, if either a D2-240, D2-250-1, D2-260 or a D2-262 CPU is being used, these bits may never have to be used, but it may be an aid to help understand the data format.

Since all output points are automatically mapped into V-memory, the location of the data word that will be assigned to the module can be simply determined.

Slot 0Slot1 Slot 2Slot3 Slot 4

The individual bits in this data word location, represents specific information about the analog signal.

16pt

Input

X17

8pt

Input

Output

X20

-X27

Y17

V40500V40502

F2-08DA--2

16pt

Output Output

Y20

Y37

V40501

Data Bits

8pt16pt

Y40

Y47

BSLBSM

Y 2 0

11-10

Channel Select Outputs

Three of the outputs select the active channel. Remember, the V-memory bits are mapped directly to discrete outputs. The binary weight of these three bits determines which channel is selected. The channel to be updated is controlled by these three outputs.

Select Channel Outputs

Y36 Y35 Y34

– – – 1 – – X 2 – X – 3 – X X 4 X – – 5 X – X 6 X X – 7 X X X 8

DL205 Analog I/O Manual, 7th Edition, Rev. G

V40501

=channel select outputs

Channel Number

Selected

BSLBSM

Y 2 0

Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

V40501

Analog Data Bits

The ﬁrst twelve bits represent the analog data in binary format.

Bit Value Bit Value

0 1 6 64 1 2 7 128 2 4 8 256 3 8 9 512

= databits

4 16 10 1024 5 32 11 2048

Output Enable

The last output can be used to update outputs. If this output is OFF, the outputs are cleared.

Y 3 7

= output enable

Module Resolution

Since the module has 12-bit resolution, the analog signal is converted into 4096 counts ranging from 0–4095 (212). For example, for a 0–10 V range, send a 0 to get a 0V signal, and 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 equation shown.

BSLBSM

01110987654321

BSLBSM

Y 2 0

10V

0-- 10V

Resolution = 4095

H – L

H = High limit of the signal range

0 4095

L = Low limit of the signal range

The table below shows the smallest change in signal level due to a digital value change of 1 LSB count.

Smallest Output

Change

Voltage Range Signal Span Divide By

0–5 V 5 volts 4095 1.22 mV 0–10 V 10 volts 4095 2.44 mV

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Writing the Control Program

Calculating the Digital Value

The control program must calculate the digital value that is sent to the analog output. Several methods can be used to do this, but the best method is to convert the values to engineering units. This is accomplished by using the formula shown.

Adjustments may need to be made to the formula depending on the scale of the engineering units.

Consider the following example which controls pressure from 0.0 – 99.9 psi. Using the formula will calculate the digital value to be sent to the analog output. The example shows the conversion required to yield 49.4 psi. The multiplier of 10 is because the decimal portion of

49.4 cannot be loaded in the program, so it is shifted right one decimal place to make a usable value of 494.

4095

A = U H – L

A = Analog Value (0 – 4095)

U = Engineering Units

H = High limit of the engineering unit range

L = Low limit of the engineering unit range

for 0–4095 output format

A = 10U 10 (H–L) (1000–0)

4095

A = 494

4095

A = 2023

Refer to the example on the next page to write the conversion program.

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

The Conversion Program

This example program shows how to write the program to perform the engineering unit conversion to output data formats 0–4095. This example assumes that a BCD value has been stored in V2300 and V2301 for channels 1 and 2 respectively.

NOTE: The DL205 has many instructions available so that math operations can simply be performed using BCD format. Do the math in BCD, then convert to binary before writing to the module output.

SP1

LD V2300

MUL K4095

DIV K1000

OUT V2000

LD V2301

MUL K4095

DIV K1000

OUT V2001

TheLD instruction loads theengineering units used with channel 1into theaccumulator.Thisexample assumesthe numbers areBCD.Since SP1 is used, this rung automatically executes on everyscan. Yo ucoul also useanX,C,etc.permissivecontact.

Multiply theaccumulatorby4095 (tostart theconversion).

Divide theaccumulator by 1000(because we usedamultiplierof 10, we have to use 1000instead of 100).

Storethe BCDresultinV2000 (the actual steps required to send the data areshown later).

TheLD instruction loads theengineering units used with channel 2into theaccumulator.Thisexample assumesthe numbers areBCD.Since SP1 is used, this rung automatically executes on everyscan. Yo ucoul also useanX,C,etc.permissivecontact.

Multiply theaccumulator by 4095(to startthe conversion).

Divide theaccumulatorby 1000(becauseweusedamultiplier of 10, we have to use 1000instead of 100).

Storethe BCDresultinV2001 (the actual steps required to send the data areshown later).

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Writing Values: Pointer Method and Multiplexing

There are two methods of reading values:

• Pointer method

• Multiplexing

The multiplexing method must be used with a D2-230 CPU. The multiplexing method must also be used with remote I/O modules (the pointer method will not work). Either method can be used with the D2-240, D2-250-1, D2-260 and D2-262 CPUs, but for ease of programming it is highly recommended to use the pointer method.

Pointer Method for the D2-240, D2-250-1, D2-260 and D2-262 CPUs

The D2-240, D2-250-1, D2-260 and D2-262 CPUs have special V-memory locations assigned to each base slot that will greatly simplify the programming requirements.

These V-memory locations allow you to:

• Specify the data format

• Specify the number of channels to scan

• Specify the location of the data that will be written to the module

NOTE: D2-240 CPUs with ﬁrmware release version 3.0 or later and. D2-250-1 CPUs with ﬁrmware release version 1.33 or later support this method.

The following example program shows how to setup these locations. Place this rung anywhere in the ladder program, or in the initial stage if stage programming instructions are being used. V2000 is used in the example but any user V-memory location can be used. In this example the module is installed in slot 3. Be sure to use the V-memory locations for the module placement. The pointer method automatically converts values to BCD.

11-14

SP0

8 K 88

OUT V7663

LDA O2000

OUT V7703

-or-

Loadsaconstant that specifies the numberofchannelstoscan and thedataformat.The lowerbyte, most significantnibble (MSN) selects the dataformat(0=BCD, 8=Binary),the LSNselects the numberofchannels(1--8).

Thebinaryformatisusedfor displayingdataonsomeoperator interfaces.The D2-230 and D2-240 CPUs do not support binary math functions, whereasthe D2-250-1, D2-260, and D2-262 do.

Special V-memory location assignedtoslot3that contains the numberofchannelsto scan.

This loads an octalvalue forthe firstV-memorylocationthat will be used to storethe output data. Forexample,the O2000 entered here would designatethe following addresses:

Ch1--V2000, Ch 2--V2001.....Ch8 -- V2007

Theoctal address(O2000)isstoredhere. V7703isassignedtoslot 3 and acts as a pointer,whichmeans theCPU will usethe octal value in this location to determine exactlywheretostore the output data.

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

The following tables show the special V-memory locations used by the D2-240, D2-250-1, D2-260 and D2-262 for the CPU base and local expansion base I/O slots. Slot 0 (zero) is the module next to the CPU or D2-CM module. Slot 1 is the module two places from the CPU or D2-CM, and so on. Remember, the CPU only examines the pointer values at these locations after a mode transition. Also, if the D2-230 (multiplexing) method is used, verify that these addresses in the CPU are 0 (zero).

The table below applies to the D2-240, D2-250-1, D2-260 or the D2-262 CPU base.

CPU Base: Analog Output Module Slot-Dependent V-memory Locations

Slot No. of Channels Storage Pointer

The table below applies to the D2-250-1, D2-260 or the D2-262 CPU base 1.

Expansion Base D2-CM #1: Analog Output Module Slot-Dependent V-memory Locations

Slot No. of Channels Storage Pointer

The table below applies to the D2-250-1, D2-260 or the D2-262 CPU base 2.

Expansion Base D2-CM #2: Analog Output Module Slot-Dependent V-memory Locations

Slot No. of Channels Storage Pointer

0 1 2 3 4 5 6 7 V7660 V7661 V7662 V7663 V7664 V7665 V7666 V7667 V7700 V7701 V7702 V7703 V7704 V7705 V7706 V7707

0 1 2 3 4 5 6 7 V36000 V36001 V36002 V36003 V36004 V36005 V36006 V36007 V36020 V36021 V36022 V36023 V36024 V36025 V36026 V36027

0 1 2 3 4 5 6 7 V36100 V36101 V36102 V36103 V36104 V36105 V36106 V36107 V36120 V36121 V36122 V36123 V36124 V36125 V36126 V36127

The table below applies to the D2-260 and D2-262 CPU base 3.

Expansion Base D2-CM #3: Analog Output Module Slot-Dependent V-memory Locations

Slot No. of Channels Storage Pointer

0 1 2 3 4 5 6 7 V36200 V36201 V36202 V36203 V36204 V36205 V36206 V36207 V36220 V36221 V36222 V36223 V36224 V36225 V36226 V36227

The table below applies to the D2-260 and D2-262 CPU base 4.

Expansion Base D2-CM #4: Analog Output Module Slot-Dependent V-memory Locations

Slot No. of Channels Storage Pointer

0 1 2 3 4 5 6 7 V36300 V36301 V36302 V36303 V36304 V36305 V36306 V36307 V36320 V36321 V36322 V36323 V36324 V36325 V36326 V36327

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Continued

Writing Data Example (Multiplexing)

The following example shows how to write the data to be sent to the output using the multiplexing method. This can be used with all DL205 CPUs.

C10

LD V2007

BIN

ORD

K7000

OUT

C10

OUT

Restarts the updatesequence.

Updates channel 8.

LD V2006

BIN

ORD

K6000

LD V2005

BIN

ORD

K5000

LD V2004

BIN

ORD

K4000

Updateschannel7.

OUT

Updateschannel6.

OUT

Updateschannel5.

OUT

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Writing Data Example (Multiplexing) continued

SP0

LD V2003

BIN

ORD

K3000

LD V2002

BIN

ORD

K2000

LD V2001

BIN

ORD

K1000

LD V2000

BIN

Updates channel 4.

OUT

Updates channel 3.

OUT

Updates channel 2.

OUT

Updates channel 1.

SP1

ORD

OUT

OUT V40501

Y37

OUT

Sends thedatatothe module.Our example starts with V40501, but the actual value dependsonthe location of themoduleinyour application.

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Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output

Write Data to One Channel

The following example can be used if only one channel is to be written to, or if the outputs are to be controlled individually. Don’t forget to either embed the sign information or use the sign output bit for bipolar ranges.

SP1

LD V2000

BIN

ANDD K0FFF

OUT V40501

Y34

RST

Y35

RST

Y36

RST

Y37

OUT

TheLD instruction loadsthe data intothe accumulator.Since SP1 is used, this rung automatically executes on every scan. Youcould alsouse an X, C, etc. permissive contact.

TheBIN instruction converts theaccumulator data to binary (you must omit this step if youhave already convertedthe data elsewhere).

TheANDD instructionmasks offthe channelselect bitstoprevent an accidental channelselection.

TheOUT instruction sends the datatothe module.Ou examplestartswithV40501,but theactualvalue dependsonthe location of themodule in your application.

Y34, Y35, Y36--OFF selectschannel 1for updating.

Y37isthe output enablebit.

Analog and Digital Value Conversions

It is sometimes useful to do quick conversions between the signal levels and the digital values. This can be helpful during startup or troubleshooting. The following table shows some formulas to help with the conversions.

Range If the digital value is known

10D

0–10 V

0–5 V

A =

4095

A =

4095

For example, if a 0–10 V range is used, and a 6V signal level is needed, use the formula to the right to determine the digital value “D” to be stored in the V-memory location which contains the data.

If the analog signal level is

known.

4095

D =

(A)

10 4095

(A)

4095

D =

(A)

4095

D =

(6V)

D = (409.5) (6)

D = 2457

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DL205 Analog I/O Manual, 7th Edition, Rev. G

Analog F2-08DA-2 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Setting the Module Jumpers

Connecting the Field Wiring

Module Operation

Writing the Control Program