CHAPTER F0-08ADH-1 8-CH. ANALOG CURRENT INPUT. In This Chapter...

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1 F0-0H- -H. HPTER NLOG URRENT INPUT In This hapter... Module Specifications onnecting and isconnecting the Field Wiring Wiring iagram Module Operation Special V-memory Locations Using the Pointer in Your ontrol Program Scale onversions Module Resolution nalog Input Ladder Logic Filter

2 hapter : F0-0H- -h. nalog urrent Input 0 Module Specifications The F0-0H- nalog Input module offers the following features: The L0 and L0 will read all eight channels in one scan. The removable terminal block simplifies module replacement. nalog inputs can be used as process variables for the four () PI loops in the L0 and the eight () PI loops in the L0 PUs. On-board active analog filtering and RIS-like microcontroller provide digital signal processing to maintain precise analog measurements in noisy environments. These modules are isolated from the PL power supply logic side (00 Volt). NOTE: The L0 PU s analog feature for this module requires irectsoft Version.0c (or later) and firmware version.0 (or later). The L0 requires irectsoft version V.0, build (or later) and firmware version.0 (or later). See our website for more information: L0/0 Option Modules User Manual; th Ed. Rev., 0/

3 hapter : F0-0H- -h. nalog urrent Input The following tables provide the specifications for the F0 0H nalog Input Module. Review these specifications to make sure the module meets your application requirements. Input Specifications Inputs per module Input Range 0-0m Resolution -bit,.0µ/bit Input Type Single Ended (one common) Maximum ontinuous Overload ±m Input Impedance 00 ohms, /0W, current input Filter haracteristics Low pass, 0Hz PL ata Format -bit, Unsigned Integer, 0 FFFF (binary) or 0 () Sample uration Time 0.ms (time to % of full step change per channel) ll hannel Update Rate.ms Open ircuit etection Time Zero reading within s onversion Method Successive pproximation ccuracy vs. Temperature ±0PPM/ Maximum Maximum Inaccuracy 0.% of range (including temperature changes) Linearity Error (End to End) ±0 count maximum; Monotonic with no missing codes Input Stability and Repeatability ±0 count maximum Full Scale alibration Error (incl offset) ±0 count maximum Offset alibration Error ±0 count maximum Maximum rosstalk at, 0 Hz and 0 Hz ±0 count maximum Recommended Fuse (external) Littelfuse Series,.0 fuse External V Power Required m ase Power Required (.0V) m Each channel requires words of V-memory irrespective of the format used. General Specifications Operating Temperature 0 to ( to F) Storage Temperature -0 to 0 (- to F) Humidity to % (non-condensing) Environmental air No corrosive gases permitted (EN- pollution degree ) Vibration MIL ST 0. Shock MIL ST 0. Field to Logic side Isolation 00V applied for second (00% tested) Insulation Resistance >0M 00V NEM IS-0; Impulse ms pulse; RFI, (MHz, Noise Immunity 0Mhz cm); Worst case error during noise disturbance is.% of full scale gency pprovals UL0; UL00- Zone Module Location ny slot in a L0 or L0 System Field Wiring Removable Terminal lock Weight g (. oz.) 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

4 hapter : F0-0H- -h. nalog urrent Input 0 onnecting and isconnecting the Field Wiring WRNING: efore removing the analog module or the terminal block on the face of the module, disconnect power to the PL and all field devices. Failure to disconnect power can result in damage to the PL and/or field devices. 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. o not ground the shield at both the module and the source. o 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. heck local and national codes to choose the correct method for your application. The F0 0H does not supply power to field devices. You will need to power transmitters separately from the PL. To remove the terminal block, disconnect power to the PL and the field devices. Pull the terminal block firmly until the connector separates from the module. You can remove the analog module from the PL by folding out the retaining tabs at the top and bottom of the module. s the retaining tabs pivot upward and outward, the module s connector is lifted out of the PL socket. Once the connector is free, you can lift the module out of its slot. NOTE: The F0 0H analog module cannot sense the loss of analog input signals in 0 0m loops. Terminal lock Specifications Number of Positions Re-Order Number 0-- Pitch. inch (.0 mm) Wire Range -WG Solid or Stranded onductor; Wire strip length /" (-mm) Screwdriver Size (Slotted) 0.T x.w mm (part number N-SS) Screw Size M. size Screw Torque. inch-pounds (. Nm) L0/0 Option Modules User Manual; th Ed. Rev., 0/

5 hapter : F0-0H- -h. nalog urrent Input Wiring iagram Use the following diagram to connect the field wiring. If necessary, the F0 0H terminal block can be removed to make removal of the module possible without disturbing field wiring. -wire 0m Transmitter -wire 0m Transmitter -wire 0m Transmitter -wire 0m Transmitter + urrent Loop Transmitter Impedance Manufacturers of transmitters and transducers specify a wide variety of power sources for their products. Follow the manufacturer s recommendations. In some cases, manufacturers specify a minimum loop or load resistance that must be used with the transmitter. The F0-0H- provides 00 ohm resistance for each channel. If your transmitter requires a load resistance below 00 ohms, you do not have to make any changes. However, if your transmitter requires a load resistance higher than 00 ohms, you need to add a resistor in series with the module. onsider the following example for a transmitter being operated from a 0 V supply with a recommended load resistance of 0 ohms. Since the module has a 00 ohm resistor, you need to add an additional resistor. R = Tr Mr R = Resistor to add R = 0 00 Tr = Transmitter requirement R 0 Mr = Module resistance (internal 00 ohms) Supply +0V 0V -0m Transmitter Shield, h. SEE NOTE. -0m Transmitter Shield, h. -0m Transmitter Shield, h. -0m Transmitter Shield, h. SHIEL ONNETE TO SIGNL SOURE OMMON. SEE NOTE. Typical User Wiring.0 or Note : Littelfuse Series, 0.0 fast-acting fuse is recommended for all -0m current loops. Note : o not connect both ends of shield. V Power Supply H H OM H H OM OM +V 0V Two-wire Transmitter + Module hannel R Internal Module ircuitry 00 Ω 00 Ω 00 Ω 00 Ω 00 Ω 00 Ω 00 Ω 00 Ω 0V H H H H H H H H ISOLTE NLOG IRUIT POWER H OM IN ohms NLOG 0 0m F0-0H- H H H H OM H H H H OM OM +V 0V 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/ 0V

6 hapter : F0-0H- -h. nalog urrent Input 0 Module Operation hannel Scanning Sequence The L0 and L0 will read all eight channels of input data during each scan. Each PU supports special V-memory locations that are used to manage the data transfer. This is discussed in more detail beginning in the section on Special V memory Locations. Scan Read Inputs Execute pplication Program Read the data Store data Write to Outputs Scan N Scan N+ Scan N+ Scan N+ Scan N+ L0/L0 PL h,,,,,,, h,,,,,,, h,,,,,,, h,,,,,,, h,,,,,,, nalog Module Updates Even though the channel updates to the PUs are synchronous with the PU scan, the module asynchronously monitors the analog transmitter signals and converts each signal into a -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 0. milliseconds to sense % of the change in the analog signal per channel. It takes approximately. ms to sample all channels. 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. L0/0 Option Modules User Manual; th Ed. Rev., 0/

7 hapter : F0-0H- -h. nalog urrent Input Special V-memory Locations Formatting the nalog Module ata The L0 and L0 PLs have special V-memory locations assigned to their respective option slots. These V-memory locations allow you to: specify the data format (binary or ) specify the number of channels to scan (up to channels for the F0 0H ) specify the V-memory locations to store the input data L0 ata Formatting The table below shows the special V-memory locations used by the L0 PL for the F0 0H. nalog Input Module L0 Special V-memory Locations ata Type and Number of hannels Storage Pointer V00 V0 Setup ata Type and Number of ctive hannels Special V memory location 00 is used to set the data format to either or binary and to set the number of channels that will be active. For example, assume the F0 0H is installed in the option slot. Loading a constant of 00 into V00 sets channels active and causes the input data value to be read as a number. With the F0 0H in the option slot, loading a constant of 00 into V00 sets channels active, and the input data value is read as a binary number. Storage Pointer Setup V0 is a system V memory location used as a pointer to a user V-memory location where the analog input data is stored. The V memory location loaded into V0 is an octal number identifying the first user V-memory location for reading the analog input data. This V memory location is user selectable. For example, loading O000 causes the pointer to write h s data value to V000 00, h s data value to V00 00, h s data value to V00 00, h s data value to V00 00, h s data value to V00 0, h s data value to V0 0, h s data value to V0 0, and h s data value to V0 0. You will find an example program that loads appropriate values to V00 and V0 on page. MS MS V00 setup 0 0 LS 0 V00 binary setup LS 0 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

8 hapter : F0-0H- -h. nalog urrent Input 0 L0 ata Formatting Special V memory locations are assigned to the four option slots of the L0 PL. The table below shows these V-memory locations which can be used to setup the F0 0H. nalog Input Module L0 Special V-memory Locations Slot No. ata Type and Number of hannels V00 V0 V0 V0 Storage Pointer V0 V V V Setup ata Type and Number of ctive hannels V memory locations 00, 0, 0, and 0 are used to set the data format to either or binary and to set the number of channels that will be active. For example, assume the F0 0H is installed in slot. Loading a constant of 00 into V00 sets channels active and causes the input data value to be read as a number. With the F0 0H in slot, loading a constant of 00 into V00 sets channels active, and the input data value is read as a binary number. Storage Pointer Setup V memory locations 0,, and are special locations used as storage pointers. V memory address is loaded into this location as an octal number identifying the first user V memory location for the analog input data. This V memory location is user selectable. For example, loading O000 causes the pointer to write h s data value to V000 00, h s data value to V00 00, h s data value to V00 00, h s data value to V00 00, h s data value to V00 0, h s data value to V0 0, h s data value to V0 0, and h s data value to V0 0. You will find an example program that loads appropriate values to V00 and V0 beginning on page 0. MS MS V00 setup 0 0 LS 0 V00 binary setup LS 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

9 Using the Pointer in Your ontrol Program hapter : F0-0H- -h. nalog urrent Input L0 Pointer Method Using onventional Ladder Logic NOTE: The proper use of the L0 pointer requires that the V memory address be written to the special memory location on the first scan only. Use the SP0 bit as a permissive contact when using the code shown below. The example program below shows how to setup the special V memory locations. 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 math on the data, compare the data against preset values, and so forth. V000 is used in the example but you can use any user V-memory location. SP0 L K00 - or - L K00 OUT V00 L O000 OUT V0 Loads a constant that specifies the number of channels to scan and the data format. The upper byte selects the data format (i.e. 0=, =inary) and the number of channels (up to for the F0-0H-). The binary format is used for displaying data on some operator interface units. The L0 PLs 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 O000 entered here would designate the following addresses: h V000-00, h V00-V00, h V00-V00, h V00-00 h V00-0, h V0-V0, h V0-V0, h V0-V0. The octal address (O000) is stored here. V0 is assigned to the option slot and acts as a pointer, which means the PU will use the octal value in this location to determine exaclty where to store the incoming data. L0 Pointer Method Using the Iox Instruction vailable in irectsoft The following logic accomplishes the same thing as the previous ladder example, but it uses the Iox instruction NLGIN. No permissive contact or input logic is used with this instruction. This instruction operates on the first scan only. nalog Input Module Pointer Setup NLGIN ase # (K0 - Local) Slot # Number of Input hannels Input ata Format (0 - - IN) Input ata ddress I-0 K0 K K K0 V000 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

10 hapter : F0-0H- -h. nalog urrent Input 0 L0 Pointer Method Using onventional Ladder Logic NOTE: The proper use of the L0 pointer requires that the V memory address be written to the special memory location on the first scan only. Use the SP0 bit as a permissive contact when using the code shown below. Use the special V memory table below as a guide to setup the storage pointer in the following example for the L0. Slot is the left most option slot. nalog Input Module L0 Special V-memory Locations Slot No. No. of hannels V00 V0 V0 V0 Input Pointer V0 V V V The F0 0H can be installed in any available L0 option slot. The ladder diagram below shows how to set up these locations with the module installed in slot of the L0. 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. 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. In the example, V000 is used, but you can use any user V-memory location. SP0 L K00 - or - L K00 OUT V00 L O000 OUT V0 Loads a constant that specifies the number of channels to scan and the data format. The upper byte selects the data format (i.e. 0=, =inary) and the number of channels (up to for the F0-0H-). The binary format is used for displaying data on some operator interface units and the L0 display. The L0 PLs support binary math functions. Special V-memory location assigned to the first 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 O000 entered here would designate the following addresses: h V000-00, h V00-V00, h V00-V00, h V00-00 h V00-0, h V0-V0, h V0-V0, h V0-V0. The octal address (O000) is stored here. V0 is assigned to the first option slot and acts as a pointer, which means the PU will use the octal value in this location to determine exaclty where to store the incoming data. 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

11 hapter : F0-0H- -h. nalog urrent Input L0 Pointer Method Using the Iox Instruction vailable in irectsoft The following logic accomplishes the same thing as the previous ladder example, but it uses the Iox instruction NLGIN. Scale onversions No permissive contact or input logic is used with this instruction. This instruction operates on the first scan only. Scaling the Input ata Many applications call for measurements in engineering units, which can be more meaningful than raw data. onvert to engineering units using the formula shown to the right. You may have to make adjustments to the formula depending on the scale you choose for the engineering units. For example, if you wanted to measure pressure (PSI) from 0.0 to. then you would have to multiply the analog value by 0 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. nalog Value of, slightly less than half scale, should yield. PSI. Example without multiplier Units = Units = Units = H L + L nalog Input Module Pointer Setup NLGIN ase # (K0 - Local) Slot # Number of Input hannels Input ata Format (0 - - IN) Input ata ddress Example with multiplier Units = 0 x H L Units = Units = Units = H L H = High limit of the engineering unit range L = Low limit of the engineering unit range = nalog value (0 ) + L L I-0 K0 K K K0 V000 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

12 hapter : F0-0H- -h. nalog urrent Input 0 The onversion Program in Standard Ladder Logic The following example shows how you would write the program to perform the engineering unit conversion. This example assumes you have data loaded into the appropriate V- memory locations using instructions that apply for the model of PU you are using. _First Scan SP0 _On SP L K00 OUT V000 L K OUT V00 L V000 MUL V000 IV V00 OUT V00 V000/00 Loads the constant 00 to the accumulator. opies the constant 00 from the accumulator to the memory location V000 and V00. Loads the constant to the accumulator. opies the content of V000 from the accumulator to the memory location V00 and V00. Loads data from V000 and V00. Multiplies the accumulator value by 00 (previously loaded into V000 and V00). ivides the accumulator value by (previously loaded into V00 and V00). opies the content of the accumulator to the memory location V00 and V0. V00/0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

13 hapter : F0-0H- -h. nalog urrent Input nalog and igital Value onversions Sometimes it is useful to convert between the signal levels and the digital values. This is especially helpful during machine start-up 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 0m 0 =. For example, if you have measured the signal as 0m, you can use the formula to determine the digital value that should be stored in the V memory location that contains the data. = = 0 = 0 = m 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

14 hapter : F0-0H- -h. nalog urrent Input 0 Module Resolution nalog ata its Two -bit words are reserved for the analog data whether you are using or binary data formatting. The bits in the low word represent the analog data in binary format. MS MS Resolution etails Since the module has -bit resolution, the analog signal is converted into, counts ranging from 0 -, ( ). 0m signal would be 0 and a 0m signal would be. This is equivalent to a binary value of to, or 000 to FFFF hexadecimal. Each count can also be expressed in terms of the signal level by using the following equation: 0m 0m V00 V00 LS 0 0 0m Example LS 0 0 MS inary Example 0 V000 Resolution = H L H = high limit of the signal range L = low limit of the signal range The following table shows the smallest detectable signal change that will result in one LS change in the data value for each increment of the signal change. m Range Signal Span (H L) ivide y Smallest etectable hange 0 to 0m 0m.0µ LS MS = data bits 0 V000 LS 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

15 hapter : F0-0H- -h. nalog urrent Input nalog Input Ladder Logic Filter PI Loops / Filtering: Please refer to the PI Loop Operation chapter in the L0 or L0 User Manual for information on the built-in PV filter (L0/0) and the ladder logic filter (L0 only) shown below. filter must be used to smooth the analog input value when auto tuning PI loops to prevent giving a false indication of loop characteristics. Smoothing the Input Signal (L0 only): The filter logic can also be used in the same way to smooth the analog input signal to help stabilize PI loop operation or to stabilize the analog input signal value for use with an operator interface display, etc. WRNING: 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. inary ata Format Filter Using Ladder Logic SP L V000 TOR SUR V00 MULR R0. R V00 OUT V00 RTO OUT V00 Loads the analog signal, which is in binary format and has been loaded from V memory location V000 00, into the accumulator. ontact SP is always on. onverts the binary value in the accumulator to a real number. Subtracts the real number stored in location V00 from the real number in the accumulator, and stores the result in the accumulator. V00 is the designated workspace in this example. Multiplies the real number in the accumulator by 0. (the filter factor), and stores the result in the accumulator. This is the filtered value. The filter range is 0. to 0.. Smaller filter factors increase filtering. (.0 eliminates filtering.) dds the real number stored in location V00 to the real number filtered value in the accumulator, and stores the result in the accumulator. opies the value in the accumulator to location V00. onverts 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 V00 to use in your application or PI loop. 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

16 hapter : F0-0H- -h. nalog urrent Input 0 NOTE: e careful not to do a multiple number conversion on a value. For example, if you are using the pointer method in format to get the analog value, it must be converted to binary (IN) as shown below. If you are using the pointer method in inary format, the conversion to binary (IN) instruction is not needed. ata Format Filter Using Ladder Logic SP L V000 IN TOR SUR V00 MULR R0. R V00 OUT V00 RTO OUT V00 Loads the analog signal, which is in format and has been loaded from V memory location V000 00, into the accumulator. ontact SP is always on. onverts the value in the accumulator to binary. onverts the binary value in the accumulator to a real number. Subtracts the real number stored in location V00 from the real number in the accumulator, and stores the result in the accumulator. V00 is the designated workspace in this example. Multiplies the real number in the accumulator by 0. (the filter factor), and stores the result in the accumulator. This is the filtered value. The filter range is 0. to 0.. Smaller filter factors increase filtering. (.0 eliminates filtering.) dds the real number stored in location V00 to the real number filtered value in the accumulator, and stores the result in the accumulator. opies the value in the accumulator to location V00. onverts the real number in the accumulator to a binary value, and stores the result in the accumulator. onverts the binary value in the accumulator to a number. Note: The instruction is not needed to PI loop PV (loop PV is a binary number). Loads the number filtered value from the accumulator into location V00 to use in your application or PI loop. L0/0 Option Modules User Manual; th Ed. Rev., 0/

17 hapter : F0-0H- -h. nalog urrent Input Example ode to Scale a 0m Signal to (For applications where the field transmitter sends a 0m signal to the analog input card.) This example will scale the first input, a double word value located at V000 and V00, as a 0m input signal from ecause the input card ranges from 0 0m instead of 0m, an offset value must be used to deal with the 0 m values. ny value below a m (0) value is forced to a m (0) value. Load V00 with the maximum engineering value (000 in this example). Load V0 with the maximum -bit value after the m value (0) is subtracted. SP etermine if the incoming value is below m, or 0 counts. V00 K V000 K0 V00 = K If the incoming value is below m (0 count) then load the minimum count value of 0 into the accumulator. 0 If the incoming value is between m and 0m then load the incoming count value into the accumulator. 0 Scale the incoming raw count of 0 to to a value between 0 and 000. Output the value in V000. SP L K000 OUT V00 L K OUT V0 0 OUT L K0 L V000 SU K0 MUL V00 IV V0 OUT V000 0 L0/0 Option Modules User Manual; th Ed. Rev., 0/

18 hapter : F0-0H- -h. nalog urrent Input 0 Example ode to Scale a 0m Signal to inary (For applications where the field transmitter sends a 0m signal to the analog input card.) This example will scale the first input, a binary/decimal value located at V000 (the PU reserves two words for each channel so V000 and V00 are reserved), as a 0m input signal from ecause the input card ranges from 0 0m instead of 0m, an offset value must be used to deal with the 0 m values. ny value below a m (0 or h) value is forced to a m (0 or h) value. Load V00 with the maximum engineering value (000 or Eh in this example). Load V0 with the maximum -bit value after the m value (0 or h) is subtracted. SP If the incoming value is between m and 0m then load the incoming count value into the accumulator. V000 K L K000 IN OUT V00 L K IN OUT V0 If the incoming value is below m (0 or h) then load the minimum count value of 0 (h) into the accumulator. V000 K L < K L V000 Scale the incoming raw count of 0 (h) to (FFFFh) to a value between 0 and 000 (Eh). Output the value in V000 as a binary/decimal number. SP SU K MUL V00 IV V0 OUT V000 L0/0 Option Modules User Manual; th Ed. Rev., 0/