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PROFIBUS is an open SPECIFICATION. Every COMPANY is allowed to create a master/slave implementation. Some patents are relevant to the PROFIBUS DP specification. The patent holders have granted free of charge licenses to all members of any RPA. Non-members have to agree on a license with the patent holders.

If a company WANTS to release a PROFIBUS implementation (SOFTWARE or hardware) as an open-SOURCE solution, the rules are relevant that are agreed at the OSADL (Open Source Development Lab, see www.osadl.org). These rules say that no implementation can be released as an open-source solution if it is covered by patents. This means that neither a PROFIBUS DP slave nor master can be registered as an open source implementation.

PROFIBUS is an open specification. Every company is allowed to create a master/slave implementation. Some patents are relevant to the PROFIBUS DP specification. The patent holders have granted free of charge licenses to all members of any RPA. Non-members have to agree on a license with the patent holders.

If a company wants to release a PROFIBUS implementation (software or hardware) as an open-source solution, the rules are relevant that are agreed at the OSADL (Open Source Development Lab, see www.osadl.org). These rules say that no implementation can be released as an open-source solution if it is covered by patents. This means that neither a PROFIBUS DP slave nor master can be registered as an open source implementation.

First of all PROFIBUS is the only FIELDBUS that can be used in all parts of the factory (upstream, process and downstream). This means you can use 1 type of control system, 1 knowledge package, 1 group of spare parts and 1 design strategy.

PROFIBUS also has a very large number of manufacturers offering products and services. This means for almost every APPLICATION there is solution and enough backup products available. These products also have strengths in certain application areas such as; motion control or process control. PROFIBUS has test labs that certify products. PROFIBUS guarantees that every product always works with products from other manufacturers.

PROFIBUS has COMPETENCE Centers that support the end-users with their automation questions and last but not LEAST, Certified Training Centers provide training. People from the WORKING groups are working close together to create a better world considering the cost aspect and the environment. They have a special band! Different people from different companies can work together without political, business and personal barriers. All faces pointing to the same direction and we get the job done! The result of their hard work is that; PROFIBUS and PROFINET can save you energy, weight, materials, spare parts, documentation and a lot of effort.

First of all PROFIBUS is the only fieldbus that can be used in all parts of the factory (upstream, process and downstream). This means you can use 1 type of control system, 1 knowledge package, 1 group of spare parts and 1 design strategy.

PROFIBUS also has a very large number of manufacturers offering products and services. This means for almost every application there is solution and enough backup products available. These products also have strengths in certain application areas such as; motion control or process control. PROFIBUS has test labs that certify products. PROFIBUS guarantees that every product always works with products from other manufacturers.

PROFIBUS has Competence Centers that support the end-users with their automation questions and last but not least, Certified Training Centers provide training. People from the working groups are working close together to create a better world considering the cost aspect and the environment. They have a special band! Different people from different companies can work together without political, business and personal barriers. All faces pointing to the same direction and we get the job done! The result of their hard work is that; PROFIBUS and PROFINET can save you energy, weight, materials, spare parts, documentation and a lot of effort.

PROFIBUS and PROFINET have the fastest cycle time, which can be LESS than 1 MS. This cycle time is EXTREMELY stable which makes it Real-Time. For diagnostics we have standardized formats and MAINTENANCE tools that match perfectly with the demands that maintenance personal has.

PROFIBUS and PROFINET have the fastest cycle time, which can be less than 1 ms. This cycle time is extremely stable which makes it Real-Time. For diagnostics we have standardized formats and maintenance tools that match perfectly with the demands that maintenance personal has.

PROFIBUS can run on 12 Mbps, which MAKES it the FASTEST fieldbus in the world. The messages have only 9 BYTES overhead which makes it very efficient. An installation with 30 devices can have a cycle time of less than 1 ms. PROFIBUS is the choice for fast message delivery in the industrial automation ENVIRONMENTS.

PROFIBUS can run on 12 Mbps, which makes it the fastest fieldbus in the world. The messages have only 9 bytes overhead which makes it very efficient. An installation with 30 devices can have a cycle time of less than 1 ms. PROFIBUS is the choice for fast message delivery in the industrial automation environments.

Within PROFIBUS there is only one communication layer implemented which is; PROFIBUS DP. Based on this communication layer, several device profiles are defined in the application layer. These profiles provide common data, diagnostics and parameters for the end-user. SOMETIMES people are confused with PROFIBUS DP and PA, but the only difference is the physical INTERFACE. In fact, a PROFIBUS PA device is a PROFIBUS DP device with an application PROFILE suited for the process industry.

Within PROFIBUS there is only one communication layer implemented which is; PROFIBUS DP. Based on this communication layer, several device profiles are defined in the application layer. These profiles provide common data, diagnostics and parameters for the end-user. Sometimes people are confused with PROFIBUS DP and PA, but the only difference is the physical interface. In fact, a PROFIBUS PA device is a PROFIBUS DP device with an application profile suited for the process industry.

It is a common FACT that PROFIBUS reduces cable costs a LOT, but there is a more that comes with it:

• Reduction of cable trays
• Energy SAVINGS
• Less documentation
• Better overview
• Reduction of test time
• Less spare parts
• Easy to expand or change
• Shorter downtimes because of quick repair
• Easy to dismantle

This is only infrastructure and the initial savings. But the real money making starts with the maintenance and the OPERATIONAL costs. PROFIBUS is an excellent choice, but some training is required to get awareness about the advantages.

It is a common fact that PROFIBUS reduces cable costs a lot, but there is a more that comes with it:

This is only infrastructure and the initial savings. But the real money making starts with the maintenance and the operational costs. PROFIBUS is an excellent choice, but some training is required to get awareness about the advantages.

The PROFIBUS COMMUNICATION is specified in IEC 61158 Type 3 and IEC 61784. IEC 61158 Type 3 includes the entire range of PROFIBUS, consisting of the versions DP-V0, DP-V1 and DP-V2. IEC 61784 specifies the PROPERTIES of the Communication Profile Family CPF 3 which is PROFIBUS. Additionally, the IEC published the “Corrigendum 1/2/3” and “Implementation Guideline” RELATED to the above mentioned documents. The Documents can be PURCHASED from the IEC website.

The PROFIBUS communication is specified in IEC 61158 Type 3 and IEC 61784. IEC 61158 Type 3 includes the entire range of PROFIBUS, consisting of the versions DP-V0, DP-V1 and DP-V2. IEC 61784 specifies the properties of the Communication Profile Family CPF 3 which is PROFIBUS. Additionally, the IEC published the “Corrigendum 1/2/3” and “Implementation Guideline” related to the above mentioned documents. The Documents can be purchased from the IEC website.

NO, it is NOT mandatory for a MANUFACTURER to have a PROFIBUS master or SLAVE certified. It is highly RECOMMENDED, because in most PROJECTS only certified devices are selected. At the moment only masters and slaves can be certified. For connectors, cable and repeaters there are no certification guidelines available.

Remark: PROFIsafe and PROFINET devices MUST be certified.

NO, it is NOT mandatory for a manufacturer to have a PROFIBUS master or slave certified. It is highly recommended, because in most projects only certified devices are selected. At the moment only masters and slaves can be certified. For connectors, cable and repeaters there are no certification guidelines available.

Remark: PROFIsafe and PROFINET devices must be certified.

This is almost IMPOSSIBLE. Because of JUNCTION boxes, SPUR lines and the input resistance of the devices it is very hard to do. At the moment there is no TOOL available.

This is almost impossible. Because of junction boxes, spur lines and the input resistance of the devices it is very hard to do. At the moment there is no tool available.

In cases where the device of manufacturer-A should be replaceable by an equivalent device of manufacturer-B, the standard Ident Number is no longer sufficient because a GSD file is associated with this number. When the device is REPLACED a change in the CONFIGURATION is necessary which will lead to a DCS/PLC stop. Therefore the PNO has ASSIGNED number ranges to DEDICATED device types (Profile Ident Numbers) in combination with certain Profile GSD files. A device can support multiple Ident Numbers which are set by a parameterization tool. The end-user has to decide whether to select the Manufacturer specific Ident Number or the Profile Ident Number.

Examples:

• Transmitter 0x9700 to 0x970F
• Actuator 0x9710 to 0x971F
• Discrete input 0x9720 to 0x972F
• Discrete output 0x9730 to 0x973F

In cases where the device of manufacturer-A should be replaceable by an equivalent device of manufacturer-B, the standard Ident Number is no longer sufficient because a GSD file is associated with this number. When the device is replaced a change in the configuration is necessary which will lead to a DCS/PLC stop. Therefore the PNO has assigned number ranges to dedicated device types (Profile Ident Numbers) in combination with certain Profile GSD files. A device can support multiple Ident Numbers which are set by a parameterization tool. The end-user has to decide whether to select the Manufacturer specific Ident Number or the Profile Ident Number.

Examples:

Modern PA devices are INTELLIGENT and can execute part of the information processing in automation SYSTEMS. This was previously done by the PLCs or DCS systems. The PA profile is designed with co-operation of the process industry and defines all functions and parameters for different classes of instruments. It is based on internationally accepted function block technology.

The profile contains descriptions for the following instrument types:

• Pressure (and differential)
• Level, temperature and flow
• Analog/digital inputs and outputs
• Valves and actuators
• Analyzers

The profile is divided into 2 classes (A and B):

Class A of the profile describes COMMON parameters of simple devices. The scope is limited to the basic functions. This set consists of the process variables (e.g. temperature, pressure, level) added by measured value state, the tag name and the engineering unit.

Class B is an extension to class A and will cover more complex application functions for identification, commissioning, maintenance and diagnosis. The relationship of the parameters to the classes is VISIBLE within the parameter definitions and in the conformance statements.

To conclude: The PA profile defines cyclical data + status, diagnostic information and parameters. The PA profile assures interoperability and device exchangeability

Modern PA devices are intelligent and can execute part of the information processing in automation systems. This was previously done by the PLCs or DCS systems. The PA profile is designed with co-operation of the process industry and defines all functions and parameters for different classes of instruments. It is based on internationally accepted function block technology.

The profile contains descriptions for the following instrument types:

The profile is divided into 2 classes (A and B):

Class A of the profile describes common parameters of simple devices. The scope is limited to the basic functions. This set consists of the process variables (e.g. temperature, pressure, level) added by measured value state, the tag name and the engineering unit.

Class B is an extension to class A and will cover more complex application functions for identification, commissioning, maintenance and diagnosis. The relationship of the parameters to the classes is visible within the parameter definitions and in the conformance statements.

To conclude: The PA profile defines cyclical data + status, diagnostic information and parameters. The PA profile assures interoperability and device exchangeability

In the process industry it is common to use blocks to describe the characteristics and FUNCTIONS of a measuring/manipulation point and to represent an application through a combination of these blocks. The specification of PA devices USES this function block MODEL to present functional sequences.

Physical Block (PB):

Describes the necessary parameters and functions of the device itself (e.g. software version, serial number, vendor ID, factory reset command). There is only one Physical block in a PA device.

Transducer Block (TB):

Contains parameters which have effect or describe the type of sensor or actuator. Transducer blocks may also contain parameters for calibration and linearization. The processed information is passed on to the Function Block. If a device has more sensors, it has corresponding Transducer Blocks for every sensor.

Function Block (FB):

Contains one or more cyclically accessible INPUTS or outputs parameters (process values). These can be of analog or discrete nature. Other parameters: setup scaling, alarms and unit FACTORIZATION.

In the process industry it is common to use blocks to describe the characteristics and functions of a measuring/manipulation point and to represent an application through a combination of these blocks. The specification of PA devices uses this function block model to present functional sequences.

Physical Block (PB):

Describes the necessary parameters and functions of the device itself (e.g. software version, serial number, vendor ID, factory reset command). There is only one Physical block in a PA device.

Transducer Block (TB):

Contains parameters which have effect or describe the type of sensor or actuator. Transducer blocks may also contain parameters for calibration and linearization. The processed information is passed on to the Function Block. If a device has more sensors, it has corresponding Transducer Blocks for every sensor.

Function Block (FB):

Contains one or more cyclically accessible inputs or outputs parameters (process values). These can be of analog or discrete nature. Other parameters: setup scaling, alarms and unit factorization.

When a device has DIAGNOSTICS it indicates this during the data exchange. The MASTER will immediately fetch the diagnostics and makes the information available for the end-user. The diagnostics from devices are completely event triggered. Diagnostics are important for smooth and reliable operation. Devices report their own device STATUS and indicate when they need service. This reduces maintenance COSTS and can increase time between scheduled field VISITS.

When a device has diagnostics it indicates this during the data exchange. The master will immediately fetch the diagnostics and makes the information available for the end-user. The diagnostics from devices are completely event triggered. Diagnostics are important for smooth and reliable operation. Devices report their own device status and indicate when they need service. This reduces maintenance costs and can increase time between scheduled field visits.

It has a double meaning; if you replace a DEVICE with the same type it WORKS directly, because the configuration is stored in the control system. ALSO, you can easily INTEGRATE a new device in your configuration by IMPORTING a GSD file and synchronizing the address of the device. By serving standardized and profile based device descriptions PROFIBUS also enables a manufacturer independent device replacement.

It has a double meaning; if you replace a device with the same type it works directly, because the configuration is stored in the control system. Also, you can easily integrate a new device in your configuration by importing a GSD file and synchronizing the address of the device. By serving standardized and profile based device descriptions PROFIBUS also enables a manufacturer independent device replacement.

When a PROFIBUS DEVICE is added in the control system CONFIGURATION, the device gets NEW memory space ASSIGNED, which does NOT conflict with the existing configuration. The existing configuration and program does not need to be touched.

When a PROFIBUS device is added in the control system configuration, the device gets new memory space assigned, which does NOT conflict with the existing configuration. The existing configuration and program does not need to be touched.

1.5 MBPS is the most commonly used transmission speed. This is the default speed when you create a NEW PROJECT. Most users don’t KNOW what it is and keep this value. Our experience is that most installation are running on a speed that is much too high for the application. When the speed is LOWER you can have longer cables and less chance of disturbances.

1.5 Mbps is the most commonly used transmission speed. This is the default speed when you create a new project. Most users don’t know what it is and keep this value. Our experience is that most installation are running on a speed that is much too high for the application. When the speed is lower you can have longer cables and less chance of disturbances.

Yes, MULTIPLE (parallel) Profibus cables can be installed in a METAL conduit. It GIVES GOOD BEHAVIOUR when EMC is involved.

Yes, multiple (parallel) Profibus cables can be installed in a metal conduit. It gives good behaviour when EMC is involved.

NO, because of certain APPLICATION, protection and isolation classes, PROFIBUS DP cable can have another colour. Example: ground cable and shipboard cable are black, robust cable is green. The standard cable is always violet.

NO, because of certain application, protection and isolation classes, PROFIBUS DP cable can have another colour. Example: ground cable and shipboard cable are black, robust cable is green. The standard cable is always violet.

When the transmission speed is 1,5 Mbps or HIGHER, it is highly recommended to have at least 1 m of cable between 2 devices. De INPUT capacitance of both devices will be compensated by the cable in order to preserve the common impedance. When the devices WOULD be very close TOGETHER, there is a big chance the input capacitance CAUSES reflections in the data communication (small short circuits). The effect is much less at transmission speeds lower than 1, 5 Mbps.

When the transmission speed is 1,5 Mbps or higher, it is highly recommended to have at least 1 m of cable between 2 devices. De input capacitance of both devices will be compensated by the cable in order to preserve the common impedance. When the devices would be very close together, there is a big chance the input capacitance causes reflections in the data communication (small short circuits). The effect is much less at transmission speeds lower than 1, 5 Mbps.

Lots of users have the impression this will never cause a problem because of the high speed signal characteristics of DP cable (even if the impedance is not correct), but there are other factors that could MAKE it very unstable

• There will be too much voltage loss at the end of the cable because of the higher loop resistance of standard DP cable (110 Ohm/km). PA cable has a loop resistance of 44 Ohm/km. When it is an Ex coupler with only 12.xV output, there is a CHANGE the last devices “get lost” all the time”.
• The DP cable gets over-powered because of its “thin” 0.64 mm diameter wires. PA cable wires have a diameter between 0.8 to 1.5 mm.
• PA COUPLING components cannot handle the “thin” wires of the DP cable.
• When it is an Ex installation, the DP cable is probably not blue and not suitable for the FISCO Ex specs.

Our advice is to use only cable that COMPLIES with the PA SPECIFICATIONS.

Lots of users have the impression this will never cause a problem because of the high speed signal characteristics of DP cable (even if the impedance is not correct), but there are other factors that could make it very unstable

Our advice is to use only cable that complies with the PA specifications.

• Always use PROFIBUS cable and CONNECTORS.
• Do not exceed 32 devices per segment (including repeaters, OLMs and couplers).
• Make SURE the segment length is in contrast with the baudrate.
• Make sure every segment has powered termination on both ends.
• Avoid spur lines.
• Avoid SWAPPING the wires (A=green, B=red).
• Mark how long the cables really are and update the drawings.

YES, even PROFIBUS can get disturbed by interference caused by parallel high voltage power lines. Always try to have at least 10 cm air space between the cables (depends on the level of the voltage). Most users mix all cables in one cable tray and that OFTEN leads to unreliable behaviour. Cables that CROSS each other will not CAUSE problems. Creating distance is not the only REQUIREMENT. CORRECT shielding is also a must.

YES, even PROFIBUS can get disturbed by interference caused by parallel high voltage power lines. Always try to have at least 10 cm air space between the cables (depends on the level of the voltage). Most users mix all cables in one cable tray and that often leads to unreliable behaviour. Cables that cross each other will not cause problems. Creating distance is not the only requirement. Correct shielding is also a must.

Termination PREVENTS REFLECTIONS that can disturb the data communication. The higher the baudrate and the longer the cable, the more important termination becomes. Termination should be activated/placed at both ends of every bus segment. With PROFIBUS DP the termination is POWERED to PROVIDE an idle level when nobody is sending data. With PROFIBUS PA the termination is a combination of a resistor and a capacitor.

Termination prevents reflections that can disturb the data communication. The higher the baudrate and the longer the cable, the more important termination becomes. Termination should be activated/placed at both ends of every bus segment. With PROFIBUS DP the termination is powered to provide an idle level when nobody is sending data. With PROFIBUS PA the termination is a combination of a resistor and a capacitor.

There are lots of stories out there concerning this subject. The actual answer LIES in the electronic components of the repeater. These DETERMINE the actual “maximum NUMBER. The digitalization from and to the opto-couplers in the repeater will make bits smaller or wider. If you put too many repeaters in series, the bits differentiate too much and messages are not recognized anymore. There are also repeaters available with no limit in serial placement.

Check the manual of the repeater! It should STATE the maximum amount. For example: the Siemens repeater is 9, the Profibus is unlimited.

The second STEP is changing the bus parameters. All repeaters have a delay time. If you put a large quantity of repeaters in series you might have to change the Tslot bus parameter to a higher value.

There are lots of stories out there concerning this subject. The actual answer lies in the electronic components of the repeater. These determine the actual “maximum number. The digitalization from and to the opto-couplers in the repeater will make bits smaller or wider. If you put too many repeaters in series, the bits differentiate too much and messages are not recognized anymore. There are also repeaters available with no limit in serial placement.

Check the manual of the repeater! It should state the maximum amount. For example: the Siemens repeater is 9, the Profibus is unlimited.

The second step is changing the bus parameters. All repeaters have a delay time. If you put a large quantity of repeaters in series you might have to change the Tslot bus parameter to a higher value.

The input resistance of the DIAGNOSTIC PLUGS is approx. 1,5..2,0 MOhm (analog comparator input). This is 100 times higher as the RS 485 receiver input impedance. In theory this should not cause any problems which have not been DETECTED so far.

The input resistance of the diagnostic plugs is approx. 1,5..2,0 MOhm (analog comparator input). This is 100 times higher as the RS 485 receiver input impedance. In theory this should not cause any problems which have not been detected so far.

A lot of people are aware that TERMINATION has to be powered and activated at both ends of the CABLE. What they do not know, is that it has to be activated again when you are using repeaters, OLMs or Profibus. Every segment has to be TERMINATED! This OFTEN slips in when people are using lots of fibre optic and there is only a short length of copper cable in the CABINETS. Even this short cable has to be terminated at both ends.

A lot of people are aware that termination has to be powered and activated at both ends of the cable. What they do not know, is that it has to be activated again when you are using repeaters, OLMs or Profibus. Every segment has to be terminated! This often slips in when people are using lots of fibre optic and there is only a short length of copper cable in the cabinets. Even this short cable has to be terminated at both ends.

A short-circuit at the PROFIBUS cable can disturb a data communication in the PARTICULAR segment. The devices in that area will NOT GET damaged! The short-circuit can easily be detected with an oscilloscope and even the distance to the PROBLEM can be measured. If the end-user wants to KEEP the installation running during a short circuit.

he can PICK the following solutions:

• Install a redundant system.
• Divide the installation in multiple parallel segments coupled by repeaters, OLMs or Profibus and ComBricks.
• Install the cable in separate cable trays.

A short-circuit at the PROFIBUS cable can disturb a data communication in the particular segment. The devices in that area will NOT get damaged! The short-circuit can easily be detected with an oscilloscope and even the distance to the problem can be measured. If the end-user wants to keep the installation running during a short circuit.

he can pick the following solutions:

• Deterministic, speed, ease to use, acceptance, support, diagnostic, multi protocols.
• PROFIBUS offers a great FLEXIBILITY. This enables the application ENGINEER to make his design without COUNTING bits and bytes. One byte more is less than 1μs! Error recovery will be done quickly without user interaction.
• It easy to integrate PROFIBUS in field devices.
• PROFIBUS is a very robust protocol with OUTSTANDING error handling capabilities.
• PROFIBUS-DP allows transmission of IO-Data with short reaction time this include transportation from IO to the bus and from the bus to the application.
• PROFIBUS-DP can be configured without specific communication knowledge. The device model is exactly what matters in remote IO.
• PROFIBUS DP is what the user needs mostly.

YES, with all PROTOCOLS.

Yes, with all protocols.

A change of the cyclic LIST is possible, however due to the FAST cycle it is not necessary in typical applications. There is a possibility to send LOW frequent cyclic MESSAGES as acyclic messages.

A change of the cyclic list is possible, however due to the fast cycle it is not necessary in typical applications. There is a possibility to send low frequent cyclic messages as acyclic messages.

• There is transmission speed detection in almost every slave device as WELL as repeaters. This will enable the USER to change the Baud rate by simply changing it at the master’s site.
• PROFIBUS has enhanced transmission speed 2 TIMES. There is no problem with the various devices because all FUNCTIONS may run at a basic configuration.

It is exactly the same time as less than 1. PROFIBUS makes no difference in the format. 256 words is equal to 4096 I/O points. I’m ASSUMING that we have 256 words in each direction, 256 input words and 256 output words. A difference can occur in your master station. The PLC or PC MIGHT make a difference in CALCULATING I/O or analog values. PROFIBUS makes no difference.

It is exactly the same time as less than 1. PROFIBUS makes no difference in the format. 256 words is equal to 4096 I/O points. I’m assuming that we have 256 words in each direction, 256 input words and 256 output words. A difference can occur in your master station. The PLC or PC might make a difference in calculating I/O or analog values. PROFIBUS makes no difference.

• The best case which is 99% the NORMAL case is that the timing is absolute STABLE (5% jitter is possible due to control FUNCTIONS)
• In case of a failure (stations are dropping out) the timing can change
• 1 transmission failure will be CORRECTED within 500/100μs (1,5/12Mbaud)
• 1 station failure will add a jitter of 700/300μs
• A worst case scenario of 33ms by 1.5MBaud or 6.6ms by 12MBaud for one cycle will occur when all stations fail (in this situation the reaction time is meaningless).
• After the failure detection the timing is back to the regular cycle time.

• 1.09ms by 12MBaud
• 6,71ms by 1.5MBaud

• PROFIBUS allows replacing of devices without interrupting the bus TRAFFIC to connected NODES.
• Slave devices NEED not be configured in case of a SWITCHING in the MASTERS role.

• Various CONFIGURATION TOOLS offer such functionality as WELL the BUS monitor.
• Most users look on reaction time rather than cycle time which include the PLC scan.

Network DOWNLOAD PROTOCOL is defined in the standard.

Some System have proprietary protocols to PREVENT INCONSISTENCIES (network configuration and PLC configuration are NOT independent).

Network download protocol is defined in the standard.

Some System have proprietary protocols to prevent inconsistencies (network configuration and PLC configuration are NOT independent).

EVERY PROFIBUS Master allows DETAILED diagnostic function within the application.

• Diagnostic information of each individual slave(Type of Slave, availability, various status information)
• Diagnostic overview of all slaves
• Master Diagnostic information
• Statistic counter

Service engineers can use a bus monitor which allows tracing the bus.

• Monitoring all DATA
• HARDWARE filtering mechanism
• Time stamps
• Trigger conditions
• SPECIAL events

Every PROFIBUS Master allows detailed diagnostic function within the application.

Service engineers can use a bus monitor which allows tracing the bus.

1. Segmenting can be DONE by USE of REPEATERS or OPTICAL link modules.
2. Step-by-Step start up can be done through the connectors by using the integrated termination.

• Several diagnostic TOOLS are available which allow measuring the bus and CONNECTORS for proper installation.
• A simple electric meter will do it for most CASES (a segment unpowered has a RESISTANCE of 110 to 130 Ohms for midrange CABLE length).

• PROFIBUS FMS
• DP
• DP extensions

May USE the same link and may be IMPLEMENTED in ONE NODE.

May use the same link and may be implemented in one node.

• The protocol EFFICIENCY MAY be up to 70%.
• The configurations mentioned in the performance metrics SECTION have a efficiency of
• 40%. This figure is CONFIGURATION DEPENDENT.

This is DETERMINED by the device, the minimum WOULD be one byte.

This is determined by the device, the minimum would be one byte.

The minimum is one BYTE:

• The GRANULARITY is determined by the device.
• INTEGER, UNSIGNED, floating point, string and structures of the base types are possible.
• A node may have IO-modules with the granularity of one bit.
• There are various links available connecting subordinated bit-level BUSSES (i.e. AS-I)

The minimum is one byte:

There are several ways for PARAMETER setup:

• PROFIBUS allows the individual SET of parameters (a MAXIMUM of 237 Bytes) during the startup.
• Acyclic exchange of parameters at runtime.
• Parameter load from a PC by a SECOND master.

There are several ways for parameter setup:

PROFIBUS has a variety of error detection capabilities:

• Checkbits in every byte
• Checksum for every MESSAGE
• Start DELIMITERS for efficient frame detection
• Addressing information (SOURCE and destination)
• Inactivity detection to find out the beginning
• Transmitter CHECK at the master devices
• Monitoring the token passing procedures
• The error correction is DONE by retries.
• PROFIBUS includes message duplication capabilities

PROFIBUS has a variety of error detection capabilities:

Yes, with the function config_check after POWER up. In addition, the IDENT number is ALSO CHECKED.

Yes, with the function config_check after power up. In addition, the Ident number is also checked.

• through a so called LIVE list.
• scanning of configured SLAVES is DONE CYCLIC.
• scanning for new masters is executed all time.

• Configuration checks for duplicate ADDRESSES.
• Masters will look for duplicate addresses before entering the token ring and when unexpected FRAMES are RECEIVED.
• Slave must be set up with their Ident-number and with their configuration. In case of a mismatch, this will be reported to the master’s APPLICATION.

Two methods are SUPPORTED:

• DIP switches or similar TECHNIQUES.
• Setting of the node ADDRESS VIA the bus connection
• Any choice is possible.

Two methods are supported: