View Larger Image WW: Access Control Override I received today’s Wordless Wednesday photo from Mohammed Asif Hussain, one of Allegion’s engineers in the UAE. I have no words. You need to login or register to bookmark/favorite this content. By Lori Greene|2021-02-25T16:52:58-05:00November 18th, 2020|hc, Means of Egress, Wordless Wednesday|5 Comments Share This Story, Choose Your Platform! FacebookTwitterLinkedInRedditWhatsAppTumblrPinterestEmail About the Author: Lori Greene Related PostsNone found Recent Posts QQ: Gasketing Requirements of NFPA 101 What’s new? I’m going to tell you! FF: Backset Modification Decoded: Smoke Door Requirements of the International Building Code WW: Just a little off the side 5 Comments Mario Fernandez November 18, 2020 at 2:55 pm - Reply That is most likely the cheap version of a Trapped-Key interlock. This is a very common requirement on rooms housing high voltage switchgear rooms or dangerous equipment. The key for that padlock is most likely “captive” on the cabinet that controls the power in that room and will not be released until the equipment is de-energized. This prevents anyone from entering while the equipment inside the room is energized. Most of the time I see this arrangement using specialized surface mounted deadbolts instead of padlocks and hasps as these can be left unlocked. The deadbolts also capture the key so it cannot be removed until the door is closed and locked. Without that key, you cannot energize the equipment. https://en.wikipedia.org/wiki/Trapped-key_interlocking Lori Greene November 19, 2020 at 12:49 pm - Reply You could be right, but I wouldn’t want to be inside of the room when someone replaces the padlock! – Lori Mario Fernandez November 24, 2020 at 10:10 am - Reply Yes indeed, I would not like to be either. However, there are very high restrictions on who goes into these rooms and there are procedures in place to avoid someone being trapped inside. Again, the padlock is the cheap way of doing this and could be very dangerous if the correct procedures are not followed, and the least of your worries is being locked in the room. A 22/0.4KV distribution transformer can kill just by being switched on. Charles a November 19, 2020 at 8:43 am - Reply High security sub station !!! Jerry Austin November 20, 2020 at 7:31 pm - Reply None of the 20 or so odd buildings I have had responsibility for maintaining allowed building owner access (in several cities) to a primary powered transformer if anything was accessible. The electric utility maintained total control over access to the high voltage transformer. A primary, high voltage supplied transformer and its conductors that were totally enclosed within a cabinet that did not allow access without physically throwing the main high voltage switch to off could be unlocked although we always kept that equipment locked. The substations had major distribution breakers that controlled major branches and these had to be accessible to the building owner’s representatives but they were supplied by 480/277 volts for the most part. People should consider that our 208/120 voltage and the frequency of the power at 60 cycles per second (hertz) is fully capable of throwing a heart into uncontrolled rhythm that would be fatal should it cross the chest. Leave A Comment Cancel replyComment Don't subscribe All Replies to my comments Notify me of followup comments via e-mail. You can also subscribe without commenting.