Magnetic locks loses power occassionally - Electrician Talk - Professional Electrical Contractors Forum
CLICK HERE AND JOIN OUR COMMUNITY TODAY, IT'S FREE!
Go Back   Electrician Talk - Professional Electrical Contractors Forum > Electrical Forum > General Electrical Discussion


Reply
 
Thread Tools Display Modes
Old 08-20-2013, 09:49 AM   #1
Senior Member
 
Join Date: Jul 2012
Location: Nova Scotia
Posts: 166
Rewards Points: 281
Default Magnetic locks loses power occassionally

Hello,

I have a peculiar case where voltage fluctuations either originating at the facility or via the utility is causing magnetic locks at a facility losing power during some instances.

I wanted to inquire if the mag lock could lose power if a transformer that feeds the secondary line supply voltage to a magnetic lock receives a voltage surge/drop on its primary line.

This voltage surge/drop may be from the utility transformer or from the standby generator if there is an issue with its automatic voltage regulator.

Would there be any other reasons for voltage spikes/drops that may cause a mag lock to lose power and then come back on sporadically?

Thank you.

Regards,

Tapan Katwala.
katwalatapan is offline   Reply With Quote
Join Contractor Talk

Join the #1 Electrician Forum Today - It's Totally Free!

ElectricianTalk.com - Are you a Professional Electrical Contractor? If so we invite you to join our community and see what it has to offer. Our site is specifically designed for you and it's the leading place for electricians to meet online. No homeowners asking DIY questions. Just fellow tradesmen who enjoy talking about their business, their trade, and anything else that comes up. No matter what your specialty is you'll find that ElectricianTalk.com is a great community to join. Best of all it's totally free!

Join ElectricianTalk.com - Click Here JOIN FOR FREE


Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ElectricianTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!

Sponsored Links
Advertisement
 
Old 08-20-2013, 09:57 AM   #2
Senior Member
 
Join Date: Jan 2007
Location: Los Angeles
Posts: 758
Rewards Points: 508
Default

Put in a battery backup.
Wireless is offline   Reply With Quote
The Following 4 Users Say Thank You to Wireless For This Useful Post:
360max (08-20-2013), macmikeman (08-20-2013), sbrn33 (08-21-2013), someonespecial (08-20-2013)
Old 08-20-2013, 10:06 AM   #3
Senior Member
 
carryyourbooks's Avatar
 
Join Date: Jan 2010
Location: KATY, TX
Posts: 1,627
Rewards Points: 1,292
Default

i did one of these a couple of weeks ago. the screw that mounted it to the door went through the door. it worked fine for years and then just finally severed.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
carryyourbooks is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 08-20-2013, 01:41 PM   #4
Senile Member
 
macmikeman's Avatar
 
Join Date: Jan 2007
Location: Honolulu
Posts: 29,182
Rewards Points: 20,739
Default

Quote:
Originally Posted by Wireless View Post
Put in a battery backup.
And a supervisory circuit to let you know when the battery is draining down.


Securitron makes power supplies designed for it.
__________________
Nationalize all foreign owned farmland now. Now.
macmikeman is online now   Reply With Quote
Old 08-20-2013, 02:58 PM   #5
Senior Member
 
JRaef's Avatar
 
Join Date: Mar 2009
Location: SF Bay Area, California
Posts: 5,313
Rewards Points: 506
Default

I think it is going to depend on the nature of your "magnetic locks".

If they are ELECTRICALLY HELD (electromagnetic) locks, then any brief interruption of power will cause them to drop out, but then they should re-lock when power is restored. A battery backup is the solution to that, and if you don't have one, I'd be surprised. maybe you have one and it is no longer functioning? batteries need maintenance and checking...

If on the other hand they are Magnetically Held, as in Permanent magnet, locks, then there would be two electromagnetic coils to engage or disengage the mechanism. If that's the case, then a momentary pulse of power to one side or the other could definitely cause inadvertent operation. Typically, there would be protections against such an incident in the control system design. I did a lot of prison lockdown control systems, we isolated EVERYTHING as a precaution against just that sort of thing. If that is what is happening for you, someone likely didn't think the system through very well and that needs further exploration.
__________________
"If you don't know where you're going, then any direction will do." -- Lewis Carroll
JRaef is offline   Reply With Quote
The Following User Says Thank You to JRaef For This Useful Post:
MHElectric (08-21-2013)
Old 08-20-2013, 09:02 PM   #6
Conservitum Americum
 
LARMGUY's Avatar
 
Join Date: Aug 2010
Location: Oklahoma
Posts: 8,479
Rewards Points: 704
Default

Quote:
Originally Posted by Wireless View Post
Put in a battery backup.
Against fire code in some areas to back up a fail safe device.
__________________
Cowboy words of wisdom.
Never approach a bull from the front, a horse from the rear, or a fool from any direction.

,
LARMGUY is offline   Reply With Quote
Old 08-20-2013, 09:10 PM   #7
Conservitum Americum
 
LARMGUY's Avatar
 
Join Date: Aug 2010
Location: Oklahoma
Posts: 8,479
Rewards Points: 704
Default

Quote:
Originally Posted by JRaef View Post
I think it is going to depend on the nature of your "magnetic locks".

If they are ELECTRICALLY HELD (electromagnetic) locks, then any brief interruption of power will cause them to drop out, but then they should re-lock when power is restored. A battery backup is the solution to that, and if you don't have one, I'd be surprised. maybe you have one and it is no longer functioning? batteries need maintenance and checking...

If on the other hand they are Magnetically Held, as in Permanent magnet, locks, then there would be two electromagnetic coils to engage or disengage the mechanism. If that's the case, then a momentary pulse of power to one side or the other could definitely cause inadvertent operation. Typically, there would be protections against such an incident in the control system design. I did a lot of prison lockdown control systems, we isolated EVERYTHING as a precaution against just that sort of thing. If that is what is happening for you, someone likely didn't think the system through very well and that needs further exploration.
Good post except for the battery backup again.

Is there an access control system? The access system could be spiking and rebooting. Some activate all the relays on the board which in turn unlock the maglocks. They should be relocked though upon completion of the reboot. There could be a REX (request to exit) switch activating the door relay. There could be a wall wart transformer supplying power that is going bad. It could be a spike on the fire alarm dropping the power. Lots of stuff to consider.

Please read the fire code in your area about battery backups to a fail safe lock before you add one.
__________________
Cowboy words of wisdom.
Never approach a bull from the front, a horse from the rear, or a fool from any direction.

,
LARMGUY is offline   Reply With Quote
Old 08-21-2013, 08:53 AM   #8
Senior Member
 
Join Date: Jul 2012
Location: Nova Scotia
Posts: 166
Rewards Points: 281
Default

Thank you everyone for your insights into this issue.

I will check for any violation of fire code for fail-safe devices backed up by a battery pack, but I agree there may be a chance that it could violate the code because it being a residential facility, during a fire alarm scenario the system is expected to de-energize.

There is an access control system in place. I will look into situations that you've described as well.

Thank you once again for sharing your experience.
katwalatapan is offline   Reply With Quote
Old 08-21-2013, 10:20 AM   #9
Senior Member
 
Join Date: Jan 2007
Location: Los Angeles
Posts: 758
Rewards Points: 508
Default

Quote:
Originally Posted by katwalatapan
Thank you everyone for your insights into this issue.

I will check for any violation of fire code for fail-safe devices backed up by a battery pack, but I agree there may be a chance that it could violate the code because it being a residential facility, during a fire alarm scenario the system is expected to de-energize.

There is an access control system in place. I will look into situations that you've described as well.

Thank you once again for sharing your experience.
There are battery back ups which are part of the access control system.
Wireless is offline   Reply With Quote
Old 08-21-2013, 12:05 PM   #10
Senior Member
 
NacBooster29's Avatar
 
Join Date: Oct 2010
Location: Southern, Ma
Posts: 2,536
Rewards Points: 1,018
Default

The battery back up should not interfere with a fire alarm relay. The relay should simply break the 24v leaving the power supply to the maglocks.
Having a battery back up in maglocks is pretty standard.
If the fire alarm sounds it simply opens the relay usually I locate them adjacent to the door access system.
This is a pretty standard install.
NacBooster29 is offline   Reply With Quote
Old 08-21-2013, 02:16 PM   #11
Conservitum Americum
 
LARMGUY's Avatar
 
Join Date: Aug 2010
Location: Oklahoma
Posts: 8,479
Rewards Points: 704
Default

Quote:
Originally Posted by NacBooster29 View Post
The battery back up should not interfere with a fire alarm relay. The relay should simply break the 24v leaving the power supply to the maglocks.
Having a battery back up in maglocks is pretty standard.
If the fire alarm sounds it simply opens the relay usually I locate them adjacent to the door access system.
This is a pretty standard install.
2010 edition
Quote:
"21.9.1 Any device or system intended to electrically lock a required means of egress door in the direction of egress shall be connected to the fire alarm system serving the protected premises.
21.9.2* Electrically locked doors in a required means of egress shall unlock in the direction of egress as prescribed by other laws, codes, and governing standards."

Quote:
This requirement would typically apply to doors with electromagnetic locks (access-controlled egress doors) and delayed egress locks (special locking arrangements). One of the gray areas surrounding these two types of locks is whether battery back-up or another type of back-up power can be used to keep the doors locked during a power failure. The IBC says that these types of locks must "unlock upon loss of power controlling the lock or lock mechanism."
Quote:
Proposed in 2002
Regarding 6.15.7.3 which refers to fire alarm systems that operate on battery backup.
"SUBSTANTIATION: This proposal is based on the work of a pre-ROP task group of the TC of Protected Premises Fire Alarm Systems. The changes will not allow batteries to be used to lock exit doors when the secondary power supply for the fire alarm system is provided exclusively by batteries. Secondary power supplies that utilize generators may opt to continue to keep the doors in the locked position. This change reflects the change in the permissible secondary power supplies from the previous edition."

Quote:
The 2010 language (it moved to a different section):
"21.9.3* For all means of egress doors connected in accordance with 21.9.1, and where batteries are used in accordance with 10.5.6.1.1(1) as the secondary power supply, the batteries shall not be utilized to maintain these doors in the locked condition, unless the fire alarm control unit is arranged with circuitry and sufficient secondary power to ensure the exits will unlock within 10 minutes of loss of primary power."
Of course there is always that AHJ form with places for signatures.
__________________
Cowboy words of wisdom.
Never approach a bull from the front, a horse from the rear, or a fool from any direction.

,

Last edited by LARMGUY; 08-21-2013 at 02:19 PM.
LARMGUY is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Man loses arm from fireworks.. B4T Off Topic (Non Trade) 28 07-04-2011 08:33 AM
New England loses twice this weekend jusme123 Off Topic (Non Trade) 4 01-17-2011 07:23 AM
another shop teacher loses job wildleg Off Topic (Non Trade) 39 09-01-2010 01:02 AM
Dallas Loses!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! brian john Off Topic (Non Trade) 14 01-18-2010 08:51 AM
Darwin wins again; idiot loses nap Off Topic (Non Trade) 4 07-12-2008 09:52 AM


All times are GMT -4. The time now is 11:17 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Our Pro Sites Network
ContractorTalk.com | DrywallTalk.com | HVACSite.com | PaintTalk.com | PlumbingZone.com | RoofingTalk.com