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Choosing a Delayed Egress System: Self-Contained, or Built from Components?

Delayed egress is a process that delays unauthorized exit from a space while complying with NFPA 101 life safety code.  Use of this process is strictly regulated with the help of building inspectors and fire marshals across the United Sates.  With that in mind it is always a good idea to get your local AHJ (Authority Having Jurisdiction) on board whenever you are planning to install delayed egress on an opening.

When you beginning planning your delayed egress system you will find that many systems on the market are self-contained.    These could be delayed egress electromagnetic locks or electrified delayed egress exit devices.

Here are some examples of self-contained delayed egress maglocks:

  • SDC 1511S
  • Schlage Electronics M490DE
  • Dynalock 3101C

Here are some examples of self-contained delayed egress exit devices:

  • Detex V40 EE
  • Von Duprin Chexit
  • Sargent Electroguard

delayed-egress-anatomy
Almost all delayed egress systems are made up of the same components:

  1. Delayed egress timer and relay logic board
  2. Initiating Switch (to initiate the delayed egress process)
  3. Audible alarm
  4. Signage
  5. Reset switch
  6. Optional bypass switch
  7. Fire Alarm interface
  8. Power supply
  9. Locking device

Therefore it is possible to construct a custom delayed egress system from components.  Later I’ll talk about why you might want to choose a built-from-components delayed egress system instead of a self-contained one.   The following sections describe each part of a built-from-components delayed egress system.

Delayed Egress Timer and Relay Logic Board

This board is UL Listed and specifically designed to perform all delayed egress functions in compliance with life safety code.   Here are some examples of component boards for delayed egress:

  • Securitron XDT-12 or XDT-24
  • Seco-Larm SA-025EQ

The board is the brains of the delayed egress operation.  It has contacts to wire in switches for delayed egress initiation, fire alarm interface and system reset, timers to control nuisance and egress delay, and relays to control locks and notify external devices.

There are also delayed egress controllers that offer more features.  The following may include the delayed egress timer/relay board and some other required feature(s) such as the initiation switch or the audible alarm.

  • Alarm Controls DE-1
  • Security Door Controls 101-DE
  • Securitron BA-XDT-12 or BA-XDT-24

Initiating Switch

The switch that initiates the delayed egress process shares several characteristics with any request-to-exit switch.  To comply with life safety regulations it must require no prior knowledge to operate; it must require no more than one motion to operate; and it must be placed in relation to the door according to life safety standards in your local jurisdiction.  I think that the best possible initiation device is a mechanical push bar with a switch, such as the Adams Rite 8099-M or the Securitron EMB.  In a panic situation it remains obvious that to get out, one must push on the bar, and because it is mechanical it is unaffected by power outage.  If it is wired to open the contact when pushed, if the wires leading to it are cut it will initiate the delayed egress process.

In rare circumstances where it might be permitted, the locking device might be a fail safe electrified mortise lock that is locked on both sides, inside and out.  Then the initiation switch might be a palm switch next to the door.

Audible Alarm

The mandatory audible alarm sounds for 15 seconds before the delayed egress controller releases the locking device to allow exit.  It’s loudness must be between 81 and 88 decibels.  In some jurisdictions the alarm must be manually reset at the door; in others it may be self resetting via timer or door position switch.  Yet another reason to have a heart-to-heart talk with your local AHJ when designing your delayed egress system.

Signage

The wording on the mandatory sign must comply with life safety code.  There are minor variations in wording.  I suggest buying a sign that is part of a delayed egress system.  The sign that comes standard with the Von Duprin Chexit is readily available as a separate part.

Reset Switch

As mentioned in the “Audible Alarm” section above, a delayed egress system reset switch located at the door is mandatory in some jurisdictions.  Check with your local AHJ.  In some jurisdictions delayed egress systems are allowed to be reset by remote switch or other means, such as a door position switch.

Any kind of momentary contact switch will do the reset switch job, but delayed egress system reset switches located at the door almost always require some kind of security to prevent unauthorized resetting.   Standalone keypads or key switches are often used for this purpose.  Delayed egress systems can also be integrated into existing access control.

Optional Bypass Switch

Not required but often needed, the optional bypass switch allows authorized personnel to exit without triggering the delayed egress system.  Again, any momentary contact switch will do, but usually some security is required.  If you are using a keypad as the system reset switch and the keypad has more than one relay, you can program the second relay to be the bypass switch.

If access from the exterior side is required a bypass switch is required on that side.  Sometimes security is not needed from the exterior side.  In that case a simple momentary contact pushbutton will do the job.

Fire Alarm Interface

The mandatory fire alarm interface allows enables fire alarm panel to deactivate the delayed egress system immediately in the event of a fire alarm.  This is an integral part of the life safety code that allows a delayed egress system to exist.  Therefore, if your building does not have a fire alarm panel, without special permission from the local AHJ you cannot have a delayed egress system.

Power Supply

All delayed egress systems I have had experience with run on low voltage power that comes from a low voltage power supply.  Generally delayed egress systems require regulated and filtered power at 12 or 24 volts.  Delayed egress controllers draw very little current, but as will all electrically operated systems, the current draw of all attached devices must be taken into account when selecting a power supply.

Locking Device

The locking device must be electrically locked and fail safe from the egress (interior) side.  The most frequently used locking device in a component based delayed egress system is the electromagnetic lock.

Why Build a Delayed Egress System?

Why would you put together a delayed egress system from components when there are so many good self-contained systems?

  1.  To Save Money.  Piecing together a delayed egress system can be significantly cheaper than buying a self contained delayed egress system.
  2.  To take advantage of existing hardware.  For example, if there is already an electromagnetic lock on the door, adding the other components is relatively easy.
  3. Conditions at the door prohibit use of a self contained delayed egress system.  For example, door size or the presence of existing hardware may require the installer to seek a more creative solution.

 





Bottom line, unless you have a prison, you cannot lock ’em in.  Well, not without permission.  🙂

Multi-function Doorways, Part Two

Secured stairwell doors are among the most basic multi-function door applications.  In most jurisdictions they must (usually)* be both unlocked and positively latched in the event of a fire.  Unlocked so that if a person, fleeing into the stairwell during a fire, finds the stairwell full of smoke, they can safely exit the stairwell.  Positively latched so that the door will remain latched closed against the spread of the fire.

Until there is a need for access control, a passage function mortise lock, cylindrical lock with UL listed latch or exit device with passage function trim are fine.  The application begins to get interesting when the need arises to lock a stairwell door.

Right up front, electric strikes are out of the question because of the unlocked/positive latching requirement mentioned above.   It is not possible to positively latch a door when the electric strike is unlocked.  There is no such thing as a fire rated, fail safe electric strike.  If you configure a fire rated electric strike to be fail safe it voids the fire rating.

Since electric strikes are unusable for this application, that leaves either electric locks or electromagnetic locks.  Both have advantages and disadvantages.  Fail safe electric locks positively latch whereas mag locks allow the installer to us the existing hardware on the door to accomplish positive latching.  Electric locks require running wire through the door and some means of getting the wire from the frame into the door, such as an electric through-wire hinge.  Not all inspectors like electromagnetic locks, so before you install them be sure to check with your local Authority Having Jurisdiction (AHJ ) – that is, Fire Marshal or Building Inspector.

If the stairwell door already has a fire rated exit device installed, there is probably a fail safe electrified trim available for it.  Once again, this means an electric through-wire hinge or other power transfer device would be required.  Sometimes existing exit devices are incompatible with the electrified trims available for that brand and model of device.  If that is the case, the exit device might have to be replaced with one that is compatible with electrified trim.

Alternatively, there are after market request to exit (a.k.a. RX) switches available for most exit devices.  One could be used to release an electromagnetic lock on the stairwell door.

Usually it is required that all electric locking devices on stairwell doors be controlled by the fire alarm panel.  When the fire alarm is in a state of alarm, it unlocks all the stairwell doors.  Two conductor wire is run from the fire alarm panel contacts to a special fire alarm relay in the power supply that powers the electric locks on the stairwell doors.  The alarm panel opens the circuit, causing the state of the fire alarm relay to change, thus powering down the fail safe locks and thereby leaving them unlocked.

An important detail:  technically speaking, according to most building and life safety codes, fire rated doors can only be modified in a fire rated shop.  Therefore if you field cut a raceway for an electric wire through the cross members of the door, for example, you are probably voiding the fire rating.  I have never heard of anyone being called on this, but it is good to keep in mind.  Just like it is good to keep in mind that the AHJ has total authority over what you can or can’t install.  Best make sure you’re on the same page with her or him, otherwise they do have the power to make you remove what you installed and replace both door and frame to repair the damage.

Happy hardware and good luck to you.


*Some jurisdictions specify that not all stairwell doors need be unlocked in the event of a fire, only certain doors.  For example, I have known some places where code was the door had to be unlocked at every fourth floor.  Check with your local AHD to find out what the rules are for your location.


Glass Door Electric Locking Solutions

Installing an electric locking system on an existing, currently unsecured all-glass or Herculite door can be a challenge for the security professional, but there are solutions.  Here are a few:

Electromagnetic Locks

Securitron Glass Door Solution

The Securitron solution to the glass door locking problem is… glue.   When I sell this solution, I usually use:

  • M62G (1200 lb. holding force electromagnetic lock with conduit fitting)
  • AKG (adhesive kit for glass doors)
  • GDB (glass door bracket for armature)

For all glass doors with all glass headers, I also use the HEB-G header extension bracket.  This can also be glued in place using the Securitron AKG.  Since the AKG includes enough glue to do 10 glass-door mag installs, there is more than enough to do one all-glass door and one all-glass header.

Everybody Else’s Mag-Lock-for-Glass-Door Solution

As far as I know, no one besides Securitron really deals with the situation of an all glass header.  For all-glass doors, all the other companies that make electromagnetic locks use variations of the HDB, or Herculite Door Bracket.  This bracket is a U-channel that slides down over the top of the door.  It’s a clip-on system:

Illustration from Rutherford Controls web site

The Herculite door bracket concept seems to work well except in cases were there is a reduced gap between the top of the door and the header.  In that case the U-channel idea is out because the HDB bracket will keep the door from closing.  Then it’s the Securitron and the glue or something else altogether.

RCI Cushion-Lok

A pricey but classy and easy to install alternative to the electromagnetic solution is the Rutherford Controls Cushion-Lok.  The Cushion-Lok is a specially constructed, fail safe electric strike and passive latch that gently locks the door upon closure.   Shown below is the RCI 3360 which is pre-installed on patch fittings that slide onto the glass of the door and “frame” when the entire doorway – door, lintels and header – is made of glass.

Not shown is another version for use with a wood or metal frame and Herculite door.

It is worthwhile to note that the reason security professionals are faced with installing electric locks on existing all-glass doors is because of a lack of planning on the part of the architect or project manager.  It is much easier for a glass door manufacturer to pre-install a locking system than it is for a security professional to install it after the fact.


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