If you are responsible for specifying a motorised door opening system, please read the following.
C.A.P Security has been established since 1996 and has a great deal of experience in the supply installation and repair of electric door motors. We can appreciate that specifier’s/client’s are busy and are not likely to fully understand all the options available for the control of motorized entry doors and often simply specify a simple description such as “Motorised door opener”.
We have written the following explanations on the basis that a person reading the information could select what they require and by doing so would be creating a detailed specification; others reading this document would gain an insight into the many options available when installing a door motor.
DOORS
An electric door motor can be fitted to operate more or less any domestic or commercial door (PVCU, Steel, Timber), however it is essential that the door used swings freely and that no add on or built in hydraulic closer are installed. Whilst the door(s) may be operated via an access control system, overnight security is always increased by the installation of a manual key operated dead lock. Unless the door has concealed hinges it is recommended that finger trap guards (which are unsightly) are fitted to each door covering the gap on the hinge side.
If a draught lobby is not part of the design then two doors opening to ninety degrees, holding open for two seconds then closing will allow a lot of cold air into any building, in such circumstances a door isolation switch should be considered so that one door could be switched off as required.
MOTOR
Motors are either domestic or commercial and have the option of a backup battery so that the motor can be used for a limited time in the event of a power failure. If the door is to be frequently used by independent disabled users the backup battery option should be chosen. Commercial motors can be used manually when switched off and offer internal adjustment for the speed of swing and the time open before the door automatically closes, further more a door motor will only operate in one direction meaning doors cannot swing both ways (in and out).
On double doors the two overhead motors required can be installed inside one continuous housing (at an extra cost) stretching across the top of both doors.
MEANS OFF OPERATION
A motor simply requires an electrical signal in order for it to open a door, devices such as a keypad, proximity reader, radio operation, a push button or touch to exit button can be used to open a door. PIR’s can also be used (mounted either side of the door) if full automation is required, in such a case any persons walking up to or near the door would cause it to open. A touch to exit button (will not work if a user is wearing a glove) should be used to comply with building regulations part M as it stipulates that the means of exit (e.g. button) could be used with a clenched fist. Radio gear is particularly useful for wheelchair users as a radio fob (issued to the user) can be used from a distance to command a door to open, then after passing the open door, used to shut it (in the case of radio operation the door will not automatically close). If means of exit is by a push or touch to exit button, mounting the button on the door frame will force wheelchair users to manoeuvre twice in order to exit and will require a longer door open time, the button should be mounted away from the door with a second button next to the door for other users. A proximity reader can be fitted inside (behind the glass) and operated from outside in order to prevent vandalism.
A useful facility for entry of disabled persons but also keeping heating costs down is PIR automated entry, this means the doors open and close via the detection of movement so will not stay open for long, combined with a large entry button marked with a wheelchair symbol. Pressing the large button will cause the doors to open and stay open for thirty seconds thus allowing the wheelchair user ample entry time.
LOCKING
Besides a dead lock being used overnight (or as required), if the door is to be used as part of an access control system, a means of electrical locking has to be installed. Hidden magnets and solenoid bolts are very kind on the décor, however hidden magnets offer little holding force and solenoid bolts cost hundreds of pounds and require the door to close to 1mm of accuracy every time. A magnetic lock hanging below the top cross member of the frame is by far the most economical and simplest form of reliable locking though not friendly on the eye! If a single door is installed and is fitted with a split spindle and sprung mortice bolt, an electric latch release can also be used. In many cases doors are not locked during the day and locked by key at night.
SAFETY
Part M building regulations require safety sensors (which cost around £200 each) to be fitted to the outside of the door so that if it were opened onto persons the door would stop prior to any collision. The same sensor can be fitted inside the door (if required) in situations where the door could close onto people who are slow in clearing the swing of the door. The same safety sensors can be a nuisance as they will prevent a door from opening if persons are standing directly in front. Furthermore; if persons are likely to approach the swing of the door at ninety degrees (e.g. a door opening onto a walkway or corridor) then physical barriers should be installed to prevent this from happening.
If the doors are to be classed as fire exits any means of electrical locking must automatically release if a fire bell is ringing, this is achieved by adding a simple relay to the nearest fire bell and linking it back to the door motor, further more a green emergency break glass should be fitted adjacent to the door so that the power to any electrical locking devices can be removed in the event of a non fire related emergency.
If a push to open button is positioned outside then consideration should be given to its position and use by wheelchair user, a pillar mounted button aids a wheelchair user but the pillar itself could become a hazard for a partially sighted person!
Part M building regulations require safety barriers to be used if a door swings into the face of persons walking across the opening.
ACCESS CONTROL
An access control system allowing speech from a locked door to an internal handset can be easily linked to a door motor so that pressing the handset door release button unlocks and opens the door.
PHOTOGRAPHS
We can provide photographs of devices installed to working doors to any interested party who wishes to contact us on the above telephone number.
DESIGN
If a specifier wishes to send us a plan of a door area detailing the use of the areas inside and out (e.g. reception hall and pavement requiring locked doors with access control) we are willing to provide a no obligation specification which we would consider to be the most practical and safe for the intended use, we will always presume that exit doors open out and that a fire alarm link will be required. We do not object to our design being used as a specification and tenders sought from our rivals, if this is to be the case please ask for a detailed specification which can be sent to others. Please note we have found that some rivals have totally ignored specifications and tendered on their own deign regardless of what has been asked for!