Patent Description:
Process control systems are generally known in the prior art. Process control systems comprise several different hardware units, for example, at least one I/O module with several signal conditioning units, a power source, a communication interface unit and a control unit. Process control systems are used among others to control complex production plants, e.g. in process industry or automobile industry. For example, such a system was developed by the applicant under the type designation ABB Ability System 800xA Select I/O.

The document <CIT> discloses a peripheral system provided with a plurality of assemblies mountable on a carrier and provided for connecting the process periphery to one or more automation devices. The assemblies of said peripheral system comprise each a base module (terminal module) and an electronics module, for example an electronics module in the form of an I/ O module, which can be plugged onto the base module. The base modules of two adjacent assemblies are connected to each other via a suitable bus connection means. A process line can be connected to the corresponding input or output of both base modules by means of a redundancy adapter.

It has now become apparent that there is a further need to provide I/O channels of an I/O module redundantly in a simple and safe way.

In view of the above, it is an object of the present invention to provide a possibility to provide I/O channels of an I/O module redundantly in a simple and safe way. These and other objects, which become apparent upon reading the following description, are solved by the subject matter of the independent claims. The dependent claims refer to preferred embodiments of the invention.

According to an aspect of the present disclosure, a terminal block unit for an input/output device of a modular process control system is provided, comprising:.

Notably, the terminal block unit is preferably configured to be directly housed in a pair of two adjacent slot elements of a module termination unit, i.e. no further contact elements, units, modules, etc. are arranged between the slot elements of the module termination unit and the plug/socket/connector of the terminal block unit.

In an embodiment of the terminal block unit, the parallel connection is provided by means of a hard wiring and/or by means of an electronic redundancy circuit comprising electronic elements, like elements for voltage, power limiting and common current shunt, or something else as fuse.

In an embodiment of the terminal block unit, the terminal block unit provides no direct communication channel between two redundant signal conditioning units.

In an embodiment of the terminal block unit, the terminal block unit comprises a redundancy contact element configured to provide a communication link between the redundant signal conditioning units. The generic input/output unit handles the communication between a fieldbus communication interface and the signal conditioning units. The generic input/output unit communicates upstream with the fieldbus communication interface using, for example, Modulebus, and downstream with up to various signal conditioning units, e.g. up to <NUM> signal conditioning units. Such generic input/output units may be used in a single or a redundant mode.

In an embodiment of the terminal block unit, the terminal block unit comprises only two slot elements configured to receive only the two redundant signal conditioning units.

In an embodiment of the terminal block unit, the terminal block unit comprises at least one blocking element configured to prohibit the insertion of certain (e.g. unsupported signal family types) signal conditioning units in the slot elements, e.g. intrinsically safe signal conditioning units, 24V signal conditioning units, high voltage signal conditioning units and/or any other signal type family, wherein the blocking element is preferably arranged at the slot elements.

In an embodiment of the terminal block unit, the terminal block unit comprises coding elements configured to mate with coding elements of a signal conditioning unit for determining the type of signal conditioning unit.

In an embodiment of the terminal block unit, the terminal block unit comprises identification elements configured to provide information to the signal conditioning unit that the terminal block unit is a redundant terminal block unit for receiving two redundant signal conditioning units.

In an embodiment of the terminal block unit, the terminal block unit comprises at least one probe hole for measurement purposes, e.g. for measuring voltage, signals and/or for a communication link with a handheld device for diagnose, setting, upload measurements.

According to a further aspect, an Input/output device comprising at least one module termination unit housing at least one generic input/output unit and at least one terminal block unit as described above is provided.

In an embodiment of the input/output device, the module termination unit comprises between <NUM> and <NUM> slot elements, preferably <NUM> slot elements, housing two generic input/output units and providing <NUM> further slot elements for single termination blocks each occupying one slot element and/or (redundant) termination blocks as described above each occupying two slot elements of the module termination block.

According to a further aspect, a modular process control system is provided comprising at least one input/output device, wherein at least one terminal block unit as described above is housed in a module termination unit of the input/output device and wherein in the slot elements of the terminal block unit a pair of redundant signal conditioning units is housed.

In an embodiment of the modular process control system, the two redundant signal conditioning units are configured to read or write a process value of a field device in parallel.

In an embodiment of the modular process control system, the signal conditioning units are configured to provide an analog output, wherein both signal conditioning units share the current and drive of the total process value of the field device, wherein both signal conditioning units preferably share the current and drive <NUM>% of the total process value of the field device.

In an embodiment of the modular process control system, the signal conditioning units are configured to provide a digital output, wherein only a primary signal conditioning unit is active and a backup signal conditioning unit is continuously listening to the communication.

In the following, the present disclosure is described exemplarily with reference to the enclosed figures, in which.

In <FIG>, a terminal block unit <NUM> for an input/output device of a modular process control system is schematically shown. The terminal block unit <NUM> comprises two input/output slot elements <NUM> and <NUM>, which are configured to receive two redundant signal conditioning units (cf. Redundant signal conditioning units are preferably signal conditioning units which are identical or which at least provide the same technical function. The terminal block unit <NUM> may comprises probe holes <NUM>, <NUM> for each terminal for connecting test probes for voltage measurements. By means of a contact socked, e.g. U-shape contact element, the terminal block unit <NUM> can be housed in a pair of two adjacent slot elements of a module termination unit <NUM> (cf. Moreover, the terminal block unit <NUM> may comprise several input clamp or screw contacts <NUM>, <NUM> for inputs, like a supply voltage, a ground connections, etc. Finally, the terminal block unit <NUM> may comprise a socket <NUM> for inserting the terminal block unit in a module termination unit <NUM>.

<FIG> shows a schematic cross sectional view of an input/output device <NUM> comprising a module termination unit <NUM>, at least one terminal block unit <NUM> as shown in <FIG>, which is housed in the module termination unit <NUM> and at least two redundant signal conditioning units <NUM>, <NUM>, which are housed in the terminal block unit <NUM>. As shown in <FIG>, the terminal block unit <NUM> may also comprise a field connection <NUM>.

<FIG> shows a schematic exemplary wiring diagram of redundant signal conditioning units <NUM>, <NUM> housed in a terminal block unit <NUM> in an input/output device <NUM>. As shown, an input of a primary signal conditioning unit <NUM> and an input of a backup signal conditioning unit <NUM> are connected in parallel with a process input signal <NUM> of a field device (not shown). Moreover, also an output of the primary signal conditioning unit <NUM> and an output of the backup signal conditioning unit <NUM> are connected in parallel with at least one generic input/output unit, wherein in the shown preferred embodiment, redundant generic input/output units <NUM>, <NUM> are provided. In the preferred embodiment, the generic input/output units <NUM>, <NUM> are connected via a communication link <NUM>.

<FIG> shows a schematic top view of an input/output device <NUM> with a redundant terminal block unit <NUM> and a single terminal block unit <NUM>, wherein a slot element <NUM> of the input/output device <NUM> is not used. As shown, a process input signal <NUM> of a field device (not shown) can be connected in parallel with a redundant pair of signal conditioning units <NUM> and <NUM>. The input/output device <NUM> further comprises connector elements <NUM> to the system interface. As also shown in <FIG>, the terminal block unit <NUM> may further comprise a redundancy contact element <NUM> configured to provide a communication link between the redundant signal conditioning units <NUM> and <NUM>.

<FIG> shows the redundancy contact element <NUM> and its contacts to the redundant signal conditioning units <NUM> and <NUM> in more detail. The PCB <NUM> of the primary signal conditioning unit <NUM> with its contact pads <NUM> and <NUM> of is shown on the left side, whereas the PCB <NUM> of the backup signal conditioning unit <NUM> with its contact pads <NUM> and <NUM> is shown on the right side. By means of the redundancy contact element <NUM> a short circuit of the contact pad <NUM> to <NUM> or <NUM> to <NUM> allows a signal conditioning unit detection to the redundant terminal block. Moreover, the contact may also be used to provide a communication link for the redundant signal conditioning units. Thus, by means of this double function the number of necessary contact elements in the terminal block unit may be reduces. At the single terminal block unit <NUM>, no such redundancy contact element <NUM> is provided such that no short circuit between the contact pads <NUM> and <NUM> could indicate the single terminal unit configuration.

In the following, a summary of the effects and advantages of the present disclosure is explained:.

For configurations where high availability is a requirement input/output channels shall be configured redundant. By means of the present disclosure, it is possible to configure redundancy on channel granular basis for safety and non-safety signals. Signals for field connections are not routed through a backplane / module termination unit (cf. This gives several technical and economic benefits. Only those input/output channels that have high requirements on availability need to be configured redundant. Other channels on same baseplate can remain in single configuration to keep high channel density and safe costs. During commissioning this gives high flexibility, it can be decided late in the project schedule whether it needs to be redundant or not. Also after several years of execution, redundancy can be added to existing channels without creating too much effort.

As there are no electrical connections between a backplane and the terminal block unit, the terminal block type can be chosen dependent on the requirements of the connected field device (e.g. single / redundant, IS / NonlS, 24V/120V/230V). Terminal blocks units and signal conditioning units that are not allowed to be combined (e.g. Non-IS SCM and IS FTB) may comprise a mechanical lock that prevents its combination. In case where multiple terminal blocks units can be used (e.g. Single / Redundant), the different terminal blocks units may comprise a self-learning function by which the plugged signal conditioning unit may read out. This information may then propagated to the engineering tools to simplify a commissioning. For special signal types, it is also possible to add electronics into the terminal block unit.

When two Signal conditioning units are expected to execute as redundant pair they have to be plugged in a redundant terminal block unit, by which they are connected to the field device in parallel. There is no direct communication channel between two redundant signal conditioning units. This reduces complexity and safes cost. Two redundant signal conditioning units may exchange information via the generic input/output unit(s) (cf. The inputs of the redundant signal conditioning units read the process value in parallel. The outputs of the redundant signal conditioning units drive the output in parallel, wherein in case of analog output signal conditioning units both modules share the current and drive <NUM>% of the total process value each. This architecture makes it possible that both primary and backup redundant signal conditioning unit have always the capability to execute all supervision. This prevents that there are any hidden errors that are first detected after a redundancy switchover. With analog redundant signal conditioning units which are capable to perform HART-Communication, only the primary redundant signal conditioning unit is active, however the backup redundant signal conditioning unit is continuously listening to the communication to make data available immediately after a redundancy switchover. In case the generic input/output unit is configured redundant as well, the backup generic input/output unit cyclically checks its communication link to both redundant signal conditioning units to safeguard availability after a redundancy switchover. Both primary and backup signal conditioning unit may generate alarm and events. This architecture reduces the risk that events are lost in case of a redundancy switchover.

It can per channel decided, if it shall be redundant or not and the signals to the terminals are not routed through the module terminal unit: Redundant terminal block units for safety and non-safety single channel universal input/output signals. Technical advantage: It can be defined in a very late step of the commissioning, if the channels shall be redundant or not. Flexible way for commissioning the system and easier to do late changes. After several years of runtime of a plant you can easily add redundant channels. One does not need to change the baseplate, but only the terminal block.

The terminal block unit type can be chosen depending what signal type is at hand, e.g. relays. Technical advantage: High voltage and the terminal block unit according to the present disclosure can be used for different signals.

Terminal block unit detection is available, since the signal conditioning unit can detect, if it is mounted in redundant or non-redundant terminal block. Technical advantage: the real configuration can be read out in order to do a much easier engineering of the system.

An implicit information exchange without a direct redundancy link is available. Data exchange in between redundant modules without separate redundancy link, but via the generic input/output unit(s). Technical advantage: Lower hardware costs.

Backup generic input/output unit may check cyclically the communication link to both redundant signal conditioning units. Technical advantage is to get fast redundancy switchover.

It is possible to actively test the ability to power a field device through temporarily increasing/decreasing the voltage of the backup channel compared to the active channel.

<NUM>/<NUM>% output value sharing of output modules may provide the technical advantage that the value drops only by <NUM>% in case of red switchover. Backup signal conditioning unit may listening to HART-Communication of the primary redundant signal conditioning unit provides the technical advantage that HART data is provided immediately after switchover.

Both redundant signal conditioning units may generate events to not lose them during redundancy switchover.

The present disclosure has been described in conjunction with a preferred embodiment as examples as well. However, other variations can be understood and effected by those persons skilled in the art and practicing the claimed invention, from the studies of the drawings, this disclosure and the claims; the scope of the invention is defined by the appended claims.

Notably, in particular, the any steps presented can be performed in any order, i.e. the present invention is not limited to a specific order of these steps. Moreover, it is also not required that the different steps are performed at a certain place or at one node of a distributed system, i.e. each of the steps may be performed at a different nodes using different equipment/data processing units.

Claim 1:
A terminal block unit (<NUM>) for an input/output device (<NUM>) of a modular process control system, comprising:
two slot elements (<NUM>, <NUM>) configured to receive two redundant signal conditioning units (<NUM>, <NUM>);
wherein the terminal block unit (<NUM>) is configured to be housed in a pair of two adjacent slot elements of a module termination unit (<NUM>) of an input/output device (<NUM>);
wherein the terminal block unit (<NUM>) provides a parallel connection of the redundant signal conditioning units (<NUM>, <NUM>) to a field device.