Emergency electric circuit arrangements for the automatic protection of electric equipment used for generation, conversion, transmission or distribution of electric power in the event of an abnormal operating condition.

Thus the scope of this subclass is limited to protective circuits for the protection of power systems for: generating electric power (alternators, generators), converting electric power (power convertors in HVDC links, power motors for industrial applications, power transformers), transmission of electric power (High Voltage AC or HVDC lines or cables) or distribution of electric power (Medium voltage lines, cables and distribution switchgear and Low Voltage lines, cables and switchgear up to the sockets of secondary customers)

In this subclass, the protective circuit arrangements are classified :

A. according to the measures taken:

B. or/and by the device being protected, e.g. transformer, motor...

C. or/and by the model used to simulate the device

D. by details of one of the above, e.g. detection means

Subgroups and head group:

If the subject-matter of a document relates to a protective circuit having different functionalities for each of which a sub-group exists, then the document is to be classified in the head-group unless a sub-group exists for this particular combination of functionalities (e.g. H02H 3/10, H02H 3/207).

All details of emergency protective circuit arrangements covering the detection means, the connection of the detection means, the transmission of signals, the data processing means, the arrangements for preventing response to transient abnormal conditions and the arrangements for supplying operative power to the circuit arrangements (e.g monitoring of power supply for trip energy, backup supply, avoid failure due to high voltage testing).

As this group concerns details of emergency protective circuits, it is normally combined with a group symbol or an Indexing Code the aspect it is a detail of. Example: WO 2009123615 (Hewlett Packard Development company) is classified in H02H 1/0007 and in H02H 3/087. In exceptional cases is inventive information classified here only.

This group is subdivided according to the electric parameter it is responsive to (e.g. overcurrent, overvoltage) and comprises all kinds of protective circuits comprising detection means for the detection of electrical variables of the power equipment to be protected (e.g. current transformers or sensors, voltage transformers or sensors), analog or digital circuits for converting, analysing or comparing the detected electrical values with pre-determined threshold levels and initiating a tripping signal to a disconnecting device to automatically disconnect the equipment to be protected from the power source to avoid or to limit damages to the equipment. These circuits may also be provided with reclosing features.

.Various types of protection are covered: overcurrent, overvoltage, undervoltage, earth fault, differential protection, distance protection, phase loss, unbalance...

This group is subdivided according to the non-electric parameter it is responsive to (e.g. temperature, fluid pressure) and comprises all kinds of protective circuits comprising detection means for the detection of non-electrical variables of the power equipment to be protected (e.g. temperature sensor, fluid pressure sensor, sensor to detect mechanical injury), analogue or digital circuits for converting, analysing or comparing the detected electrical values with pre-determined threshold levels and initiating a tripping signal to a disconnecting device to automatically disconnect the equipment to be protected from the power source to avoid or to limit damages to the equipment or to protect living beings. These circuits may also be provided with reclosing features

Protective circuits comprising simulation or modelling means for the determination of non-electrical variables of the power equipment to be protected (e.g. temperature), and comparing the simulated non-electric variables with pre-determined threshold levels and initiating a tripping signal to a disconnecting device to automatically disconnect the equipment to be protected from the power source to avoid or to limit damages to the equipment or to protect living beings. These circuits may also be provided with reclosing features.

Emergency protective circuit arrangements specially adapted for protecting specific types of electric machines or apparatus (e.g. transformers, electric motors) and effecting automatic switching in the event of an undesired change from normal electric or non-electric working conditions.

This group covers also emergency protective circuit arrangements for sectionalised protection of cable or line systems, e.g. for disconnecting a section on which short-circuit. earth fault, or arc discharge has occurred. The objectives of these type of protective circuits is to keep the power system stable and/or to minimize an outage to the greatest extend possible when abnormal electrical conditions occur (e.g. through protective device coordination).

Anti-pinching systems for car-window motors

Circuit arrangements responsive to, e.g. overcurrent, overvoltage, arc fault , for protecting solar cells used for power distribution or generation and effecting automatic protection of the solar cells array.

all aspects of circuit arrangements regarding the device coordination in an electrical network with multiple layers in a hierarchical structure and back-up protection.

All types of protective circuit arrangements for protecting power systems, machines and apparatus covered by this subclass against the damaging effects of excess current or voltage without disconnection by limiting the speed of change of electric quantities, avoiding undesired transient conditions (e.g. with filters), by providing intrinsically safe conditions (limiting both voltage and current), by limiting excess current, by limiting excess voltage, or by limiting or suppressing of earth fault currents.

Crowbars

Overvoltage protection circuits, where the integrated circuits can be considered as a black box

e.g. in case of incorrect or interrupted earth connection, in case of inverted polarity or connection, in case of incorrect phase sequence, in case of too high or too low isolation resistance, too high load, short-circuit or earth fault, in case of too high or too low voltage, or preventing unsafe switching conditions.

Protective circuits for preventing connection of outlets to power source if no load and detection of human body should be classified in H02H 5/12 and an Indexing Code given in H01H 11/00.