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---- Warning ---- Warning ---- On the XL series OCS, the serial connections are via an MJ45 socket. This socket includes both an RS232 port and an RS485 port. On some models, MJ1 and MJ2 (separate serial ports) are included in the same socket. Because this is the same type of socket that is used for Ethernet connections, there is an obviously easy way to make a connection, use a standard Ethernet patch lead with one plug cut off. --- Don't Do It --- The Ethernet wiring in the patch lead comprises four twisted pairs and in the Ethernet structure, a different push pull signal is dedicated to each pair. Twisted pair cabling is designed to minimize cross talk and interference with other circuits in close proximity because the twisted pair carries an equal and opposite signal on the two cores. The combined electrical and electromagnetic fields from a twisted pair, will cancel to zero and as such will not induce a significant signal into another circuit in close proximity. If you use a standard Ethernet cable you do not have a balanced differential signal applied to each pair, rather there are signals that are running on multiple pairs and the cross talk is seriously enhanced. The RS485 circuit is a differential circuit and if you applied connections such that the RS485 circuit was on a single twisted pair, you would a) reduce cross talk for signals getting out and causing interference, b) reduce cross talk for signals getting in and causing interference. The RS232 circuit is single ended in that there is only a single wire circuit carrying the TX information relative to a ground circuit, and a single wire carrying the RX information relative to the same ground connection. This is the wrong format for a twisted pair which must be a differential signal. Running the MJ1/MJ2 connections together down an Ethernet patch cable causes cross talk between the RS485 circuit and the RS232 circuit and will often lock up all communications to and from the PLC on all ports. The circuits must be separated as close to the socket as possible and if they need to run a distance down a similar path, they should be run in separate cables. The RS485 signals would ideally be run in a screened twisted pair cable and the RS232 in a screened un-twisted pair cable. NB: RS232 is potentially very noise sensitive and so the length / distance of the RS232 cable should be as short as possible and well clear of other electrical cables and conductors. RS485 is inherently far more noise immune and can run considerable distances without problems, but with long distances, the RS485 cable should have an impedance of 120 ohms and be terminated in 120 ohms at each end. All RS485 connections should be "daisy chained and the intermediate connection should not be terminated.

Status Word Memory allocations. Many of the inbuilt function modules in CScape have a status word requirement/option and this status word typically requires 2 x 16 bit words stored consecutively. This requires two 16 bit words to be reserved, with the name of the first word specified as the "Address". The common mistake, is to declare a single word as a global and point to that word only. The operation of the "module" passes data to both the "Address" register and the following register. If this register has not be reserved, then it can be dynamically allocated as a separate storage register for another variable and errors will occur. The safest method, is to declare an array of two words. An alternative method, is to declare two variables at consecutive memory addresses and use the lowest address word as the index. i.e. SerialStatusA at %R100 and SerialStatusB at %R101 and use SerialStatusA as the index instead of SerialStatus[0] above. Look carefully at the requirements. Some statuses require 1 word, others 2 words and some 4 words.

The Horner OCS units include a flexible inbuilt I/O configuration which is indicated by the last number of the model description. i.e. HE-XC 1Ex where the x indicates the I/O x = 0 : No analog x = 2 : 4 standard Analog Inputs x = 3 : 2 standard Analog Inputs The analog inputs are connected to the tags (memory) %AIx where x is the number of the analog input. %AI1 is analog input number one, %AI2 is analog input number 2 etc. The value read from the analog register is an integer of value 0 for minimum scale and 32000 for maximum scale. A value of approximately -8000 on a 4-20 mA input would indicate 0 mA. HARDWARE To use a standard Analog input on a Horner OCS, it is first essential to configure the input to comply with your requirements. The standard Analog inputs can be configured for 0-10Volt DC, 0-20mA, 4-20mA. - Universal inputs can be set up for alternative measurements such as temperature. These are standard on some models of OCS. To configure the input, you must : Ensure that the jumper on the I/O card is set correctly. By default, the jumper is set of current input and must be moved for a voltage input. - the jumper connects a 100 ohm resistor across the analog input. Configure CScape to read the input correctly. Open Controller | Hardware Configuration | Local I/O on the menu to show: Click on the Config Button associated with the I/O card to open the Analog Input Configuration : Adjust the input channels to suit your requirements. At the bottom of this screen, there is a filter option that is defaulted to 0. If you have major noise issues, the filter setting can be adjusted to slow the input response and mask the noise from the readings. SOFTWARE To read an analog input, you must first declare a variable of type INT at a tag (or memory) location that is correct for that input (i.e. %AI1) As the value is going to lie between 0 and 32000, you will want to scale the input to represent the actual value measured. First, determine if you are going to use an integer or a real to store the scaled value. Integer values do not include fractions so can lead to severe rounding errors unless the "units" are chosen with sufficiently small steps. e.g. a value of 0 to 10 Bar scaled and stored in Bar, will only work in steps of 1 Bar. 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Bar which is a very course measurement. If you choose to work in Bar, you can scale your variable to store mB (milliBar) but display it with three decimal points and that way get the required accuracy. Real values do store fractions, but are twice the size (32 bits long instead of 16) but are very slow and heavy on processing resources. If the CPU is very fast (small scan time) and the program is small, then working with reals is an easy option. If the CPU is slow and/or the program is large, the additional time taken to process REAL values could become a problem with a very slow scan time. For small, low cost processors, consider avoiding REAL values for faster operation. There are two scaling blocks built into CScape. - You will find them under the "Advanced" option of the Project tools box. Integer Scaling. Real Scaling. Note to use Real Scaling, you must first convert the raw (measured) value to a type REAL. Structured Text Examples : declare : Pressure_Raw Type INT at memory %AI1 Integer Scaling : Pressure_MB scaled 0 - 10000 Real Scaling : Pressure_Real scaled 0 - 10.0

The Horner OCS units include a flexible inbuilt I/O configuration which is indicated by the last number of the model description. i.e. HE-XC 1Ex where the x indicates the I/O x = 0 : No analog x = 2 : 4 standard Analog Inputs x = 3 : 2 standard Analog Inputs The analog inputs are connected to the tags (memory) %AIx where x is the number of the analog input. %AI1 is analog input number one, %AI2 is analog input number 2 etc. The value read from the analog register is an integer of value 0 for minimum scale and 32000 for maximum scale. A value of approximately -8000 on a 4-20 mA input would indicate 0 mA. HARDWARE To use a standard Analog input on a Horner OCS, it is first essential to configure the input to comply with your requirements. The standard Analog inputs can be configured for 0-10Volt DC, 0-20mA, 4-20mA. - Universal inputs can be set up for alternative measurements such as temperature. These are standard on some models of OCS. To configure the input, you must : Ensure that the jumper on the I/O card is set correctly. By default, the jumper is set of current input and must be moved for a voltage input. - the jumper connects a 100 ohm resistor across the analog input. Configure CScape to read the input correctly. Open Controller | Hardware Configuration | Local I/O on the menu to show: Click on the Config Button associated with the I/O card to open the Analog Input Configuration : Adjust the input channels to suit your requirements. At the bottom of this screen, there is a filter option that is defaulted to 0. If you have major noise issues, the filter setting can be adjusted to slow the input response and mask the noise from the readings. SOFTWARE To read an analog input, you must first declare a variable of type INT at a tag (or memory) location that is correct for that input (i.e. %AI1) As the value is going to lie between 0 and 32000, you will want to scale the input to represent the actual value measured. First, determine if you are going to use an integer or a real to store the scaled value. Integer values do not include fractions so can lead to severe rounding errors unless the "units" are chosen with sufficiently small steps. e.g. a value of 0 to 10 Bar scaled and stored in Bar, will only work in steps of 1 Bar. 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Bar which is a very course measurement. If you choose to work in Bar, you can scale your variable to store mB (milliBar) but display it with three decimal points and that way get the required accuracy. Real values do store fractions, but are twice the size (32 bits long instead of 16) but are very slow and heavy on processing resources. If the CPU is very fast (small scan time) and the program is small, then working with reals is an easy option. If the CPU is slow and/or the program is large, the additional time taken to process REAL values could become a problem with a very slow scan time. For small, low cost processors, consider avoiding REAL values for faster operation. There are two scaling blocks built into CScape. - You will find them under the "Advanced" option of the Project tools box. Integer Scaling. Real Scaling. Note to use Real Scaling, you must first convert the raw (measured) value to a type REAL. Ladder Diagram Examples : declare : Pressure_Raw Type INT at memory %AI1 Integer Scaling : Pressure_MB scaled as 0 - 10000 Real Scaling : Pressure_Real scaled as 0 - 10.0

The Horner OCS units include a flexible inbuilt I/O configuration which is indicated by the last number of the model description. i.e. HE-XC 1Ex where the x indicates the I/O x = 0 : No analog x = 2 : 4 standard Analog Inputs x = 3 : 2 standard Analog Inputs The analog inputs are connected to the tags (memory) %AIx where x is the number of the analog input. %AI1 is analog input number one, %AI2 is analog input number 2 etc. The value read from the analog register is an integer of value 0 for minimum scale and 32000 for maximum scale. A value of approximately -8000 on a 4-20 mA input would indicate 0 mA. HARDWARE To use a standard Analog input on a Horner OCS, it is first essential to configure the input to comply with your requirements. The standard Analog inputs can be configured for 0-10Volt DC, 0-20mA, 4-20mA. - Universal inputs can be set up for alternative measurements such as temperature. These are standard on some models of OCS. To configure the input, you must : Ensure that the jumper on the I/O card is set correctly. By default, the jumper is set of current input and must be moved for a voltage input. - the jumper connects a 100 ohm resistor across the analog input. Configure CScape to read the input correctly. Open Controller | Hardware Configuration | Local I/O on the menu to show: Click on the Config Button associated with the I/O card to open the Analog Input Configuration : Adjust the input channels to suit your requirements. At the bottom of this screen, there is a filter option that is defaulted to 0. If you have major noise issues, the filter setting can be adjusted to slow the input response and mask the noise from the readings. SOFTWARE To read an analog input, you must first declare a variable of type INT at a tag (or memory) location that is correct for that input (i.e. %AI1) As the value is going to lie between 0 and 32000, you will want to scale the input to represent the actual value measured. First, determine if you are going to use an integer or a real to store the scaled value. Integer values do not include fractions so can lead to severe rounding errors unless the "units" are chosen with sufficiently small steps. e.g. a value of 0 to 10 Bar scaled and stored in Bar, will only work in steps of 1 Bar. 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Bar which is a very course measurement. If you choose to work in Bar, you can scale your variable to store mB (milliBar) but display it with three decimal points and that way get the required accuracy. Real values do store fractions, but are twice the size (32 bits long instead of 16) but are very slow and heavy on processing resources. If the CPU is very fast (small scan time) and the program is small, then working with reals is an easy option. If the CPU is slow and/or the program is large, the additional time taken to process REAL values could become a problem with a very slow scan time. For small, low cost processors, consider avoiding REAL values for faster operation. There are two scaling blocks built into CScape. - You will find them under the "Advanced" option of the Project tools box. Integer Scaling. Real Scaling. Note to use Real Scaling, you must first convert the raw (measured) value to a type REAL. Structured Text Examples : declare : Pressure_Raw Type INT at memory %AI1 Integer Scaling : Pressure_MB := ScaleInt(Pressure_Raw, 0, 32000, 0, 10000); // Scaleint(Input, InputMin, InputMax, OutputMin, OutputMax) Real Scaling : Pressure_Real := ScaleReal(Any_to_Real(Pressure_Raw), 0, 32000, 0, 10.0); // ScaleReal(Input, InputMin, InputMax, OutputMin, OutputMax) Any_to_Real(Pressure_Raw) converts the integer value Pressure_Raw to a real value. This could be done outside the formula as an intermediate step; i.e. declare Pressure_Raw_Real of type REAL Pressure_Raw_Real := Any_To_Real(Pressure_Raw); Pressure_Real := ScaleReal(Pressure_Raw_Real, 0, 32000, 0, 10.0); //ScaleReal(Input, InputMin, InputMax, OutputMin, OutputMax)