Whereas the invention is applicable in general to the control of operator devices for a large vari- ety of movable members it is mainly concerned with thee control of openable building components in the form of doors and/or windows and/or similar passive ventilation members as well as movable accessories for such members, which in certain positions may ob- struct the opening or closing thereof.

Purely by way of example the invention may be applied to a ventilation system of the kind disclosed e. g. in WO 00/39506, in which operators for a number of passive ventilation devices may be controlled by a common central control unit and stringent require- ments must be set to the continued operability of all operators including access to the necessary electri- cal operating power under all circumstances, includ- ing hazard situations like development of smoke caused by fire in the building or other causes which would require opening or closing of the passive ven- tilation devices.

To ensure continued operability such ventila- tion system must, in addition to its connection with

a mains power supply have access to power for emer- gency operation in case of dropout of the mains power. To avoid excessive power consumption under emergency operation a typical solution would be to disconnect the emergency power supply from the opera- tors under no load conditions. This would be in con- flict, however, with the requirement to ensure con- tinued operability, which under standard prescrip- tions is implemented by conduct of an operability test at regularly repeated intervals, e. g. once a minute.

In large buildings with a significant number of controlled ventilation devices like windows and/or doors and operators associated therewith the require- ment to maintain continued power supply to the opera- tors also under no-load conditions put rather heavy demands to the capacity of a emergency power supply unit such as an emergency power accumulator.

On this background it is the object of the in- vention to provide a method and a control system for controlling emergency operation of electrical opera- tor devices for movable members as well as a control system for implementation of this method permitting continued conduct of a regularly repeated operability test under emergency operation, while ensuring a sig- nificantly reduced power consumption and consequently significantly reduced requirements to the capacity of the necessary emergency power supply unit such as a battery.

In accordance with the invention a method of the kind defined is characterized in that during said emergency operation power supply to the operator de- vices is generally disconnected and an operability test is conducted by temporary connection of power supply from said emergency power supply means to the operator devices.

With this method actual connection of each op- erator device to the emergency power supply, such as a battery, will under no-load conditions only be ef- fected for the duration of the operability test, which may typically be of the order of 100 ms. Thus, with the test procedure repeated at regular intervals of 100 seconds a significant reduction of power con- sumption will be obtained.

Advantageous and preferred implementations of the method are stated in dependent claims 2 to 10.

For adapting the method of the invention to a typical installation, in which a number of operator devices are served by a common central control unit and a common hazard control unit for both of which continued power supply from the emergency power sup- ply is maintained under emergency operation, the need to conduct an individual operability test for all in- dividual operators may be eliminated by routing an interrogation signal for the operability test seri- ally from the hazard control means through interface units interposed between the operator devices and the central and hazard control means.

Although, the hazard control means will thereby not be able to determine exactly by itself, from which operator a signalled error state or a communi- cated need for power supply has been sent, identifi- cation of such an operator could relatively easily be accomplished from the central control unit.

For the performance of the method a control sys- tem for the operation of electrical operator devices is characterized, according to the invention, in that means are provided for general disconnection of power supply to the operator devices during said emergency operation and for conducting said operability test by temporary connection of power supply from said emer- gency power supply means to the operator devices.

Advantageous and preferred embodiments of such a control system are stated in dependent claims 11 to 15.

In the following the invention will be explained in further detail with reference to the accompanying drawing, in which fig. 1 is a simplified block diagram representa- tion of a computer-controlled natural ventilation system embodying the invention, fig. 2 is a graphical representation of a bit se- quence use for the interrogation and operator status signals in accordance with the method of the inven- tion, and fig. 3 is a diagram representation of a switching arrangement for use in the hazard control unit in fig. 1.

In the embodiment shown in fig. 1 operators 1 for passive ventilation devices such as windows or doors are controlled by interface means comprising inter- face units 2. As seen in the figure several operators may be served from the same interface unit.

The interface units 2 communicates via a bus, like e. g. an EIB-bus 4 (European Installation Bus) with a central control unit 3, from which the opera- tion of operators 1 may be controlled independently in dependence on indoors and out doors climatic parameters.

The interface units 2 are further connected with a mains power supply 5 as well as with an emergency power supply unit 6, which may typically be a bat- tery, but could be any conventional form of emergency power source, via a hazard control unit 7. which in addition communicates with the interface units 2 via communication lines 8 and 9.

To be able to control the operators 1 and to get information on eventual error states therein the haz- ard control unit 7 has serial input and output commu-

nication lines 8 and 9. The hazard control unit 7 will send interrogation commands through the output line 8 and receive status information from the inter- face units 2 through the input line 9.

In a preferred implementation of the method ac- cording to the invention the communication between the hazard control unit 7 and the interface units 2 may be based on an asynchronous serial protocol as illustrated in fig. 2 using 6 data bits, 1 start bit and 1 stop bit. At regular time intervals, e. g. once every 100 seconds, the hazard control unit 7 will send a byte using a bit width of e. g. 11.7 ms (3/256 sec). The first four data bits will define the pre- sent condition of the hazard control unit 7, whereas the following two data bits will be zeros.

In the interface unit 2 these last two data bits will be updated to represent the status of the inter- face unit and the operators 1 connected therewith.

The interface unit 2 will then send the completed. byte (6 bit) either back to the hazard control unit 7 or to the next interface unit 2.

During emergency operation, when the system is operating on batteries, an operator power line 10 from the hazard control unit 7 to the interface units 2 will be disconnected nearly all the time and the communication and control units 2 will not be able to communicate with the operators 1. Thus, when the haz- ard control unit 7 needs operator status information a test procedure will be initiated, by which a se- quence of interrogation and answer signals will be communicated via communication lines 8 and 9 in the form of a bit sequence as illustrated in fig. 2. In connection therewith reduced power supply is con- nected to the interface units 2 via a microprocessor power line 11.

As an example, the test procedure sequence may be as follows:

Hazard control unit 7 turns motor power on line 10 on.

The interrogation bit sequence 10 00 00, e. g. with a bit definition as explained below, will be transmitted from the hazard control unit 7 to the interface units 2.

In response an operator status signal provided by the immediately preceding test procedure will be returned by the interface unit in the form of a bit sequence 10 00 xx, in which the last two bits"xx"will represent operator status data collected by the interface unit in the preceding test procedure.

"The hazard control unit 7 will now wait 2 sec- onds to allow the operator 1 to initialise and the interface unit 2 to collect data) After this delay a bit sequence 10 01 00, indi- cating that the power will be turned off, is transmitted from the hazard control unit.

In response to this new interrogation signal the bit sequence 10 01 xx, in which the two last bits have now been updated with the actual op- erator status, is returned by the interface unit to the hazard control unit.

'Power supply to the operators will now be turned of, unless the interface unit has indicated a need for power to be supplied to the operator or one of the operators served by it by setting the "power needed"flag in the two last bits in the returned operator status signal.

In the table below an example is given of the com- munication flag definition used in the interroga- tion and operator status signal, i. e. the defini- tion of the individual bits of the above-mentioned bit sequence.

Bit Controlled by 0 1 No. 0 Hazard control unit Mains power Battery power 1 Hazard control unit Operator close 2 Hazard control unit Operator open 3 Hazard control unit Oper. power ON Oper. Power OFF 4 Interface unit No power needed Power request 5 Interface unit OK Operator error Whereas bit No. 0 defines, whether the system is in regular operation with connection to the mains power supply or is in a state of battery powered emergency operation, bit No. 1 or bit No. 2 will be set by the hazard control unit 2 to the value 1 as a command to close or open a window, respectively, if definition of the position is needed.

The power needed by operators 1 is distributed from the hazard control unit 7 via the power line 10 and through the interface unit 2, which will include a fuse for each operator 1 served thereby. By setting bit No. 3 to 1 the hazard control unit 7 indicates that operation power is off and thus not available for operation of operators 1, e. g. due to mains power dropout.

If any of operators 1 served by an interface unit 2 is unable to move the window, with which it is con- nected, to the right position, this will be indicated in the operator status signal by setting bit No. 5 to the value 1 to indicate an error state.

Bit No. 4 is set by the interface unit 2 to the value 1, when a command for operation of any operator served thereby has been received, but not carried out. During emergency operation a user may be permit-

ted e. g. to close an open window or open a closed window, but only once.

Whereas the hazard control unit 7 will normally initiate the communication of interrogation and op- erator status signals, an interface unit 2 may be al- lowed to initiate communication, if closing of a win- dow is needed, when power supply is disconnected dur- ing emergency operation. This can be done by using the bits received during the immediately preceding test procedure as input to the hazard control unit 7.

When the hazard control unit 7 receives an opera- tor status signal containing a power request, i. e. bit No. 4 in the sequence being set to 1, it will turn on power and communicate a confirmation message to the interface unit with a short time delay, e. g.

0.5 seconds. Moreover, before the hazard control unit 7 disconnects the power supply, it must send a mes- sage indicating that disconnection of the power sup- ply will be effected and check that no interface unit has set the power request flag, i. e. the value 1 of bit No. 4.

The hazard control unit 7 will set the individual bits of the bit sequence illustrated in fig. 2 at the time: tset = tstart + (1 + n) * 3 * T + BitTimingError, where start is the time of the start bit front edge, n is the bit number 0... 5 and T is the timing unit, e. g. = 1/256 s = 3.906ms.

In the interface unit date sampling will be ef- fected at the time: tsamp = tstart + (1+n) * 3 * T + T + ResponseTime + BitTimingError,

And new output data will be set-up by the interface unit at the time: tout = tsamp + ProcessTime The average delay through the interface unit will be equal to: RecvResponseTime + ProcessTime + BitTimingError +T = typical 5.9ms.

As shown in the simplified block diagram in fig.

3 of the switching arrangement of a hazard control unit embodying the invention the mains power supply may comprise a mains voltage transformer 13, the sec- ondary side of which is connected to diode rectifier bridges 14 to deliver a DC voltage of 24 V for power supply of the interface units 2 and the operators 1 during regular operation.

In case of mains voltage dropout, power supply, when needed for emergency operation, will be provided from an emergency power supply unit 15 such as an ac- cumulator of appropriate capacity. In accordance with the invention the supply of power will normally be disconnected from the interface units 2 by means of a relay controlled switch 16.

For connection of a reduced power supply to the interface units 2 during the regularly repeated test procedure a semiconductor switching member 17 is con- nected in parallel with the relay switch 16. Power lines 10 and 11 in fig. 1 are connected with relay switch 16 and semiconductor switch 17, respectively.