Electro-mechanical access control products are available in different configurations including electrified cylindrical locksets, mortise locks, panic/exit devices, deadbolts, strikes and trim. Each of these devices and configurations provides similar and yet unique locking applications. One of...
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Power Transfer Hinges
In my opinion, the best solution for wood and hollow metal doors is to run the wiring using a power transfer hinge. Hinges are tamper-resistant; they blend in with the other butt hinges and can be used again on another door if needed. Costs for power transfer hinges have been reduced substantially in recent years.
Power transfer hinges are available fire listed and tested for use on fire rated doors and frames. Make sure that any hardware you placed on a door that is listed for 20 minutes or more of fire resistance, is listed for such use. To do otherwise will most certainly open you, your company and your insurance to potential liability, especially with the new Annual Fire Door Inspection requirements that are part of the newly revised NFPA 80 Standard. Better to do it right the first time to avoid some serious, costly situation in the future.
With that in mind, let's talk about how to determine the correct hinge needed for your job. When specifying the hinge, you will need the weight, the knuckles, the finish and the size. Most hinges are called full mortise hinges and this simply means that the hinge leaf is mortised into the door and frame, where the leaves sit flush with the surface of the door and frame and the only thing that sticks out is the barrel.
First, measure your hinge to determine sizing. Measure from the top of the leaf (not the barrel or pin) down to the bottom of the leaf. Most hinges are 4.5 inches high and 4.5 inches wide. They are not all this size, so you still must check to make sure. After you measure from the top to the bottom, open the door to 180 degrees, if possible, and measure from the right or left leaf edge, to the opposite edge. If you cannot get the door open this far, measure from the leaf edge to the center of the pin. This will give you half the distance and you can multiply by two, to get the actual full width of the hinge. Once you have these two numbers, you would call out your hinge, when ordering, with the height first and the width second. For example, you would request (would put down that you need) a 4.5 x 4.5 hinge. If the hinge were four and a half inches high, by four inches wide, you would request a hinge size of 4.5 x 4.0.
Next, examine the finish. If the finish is a brushed chrome, you might think it is a US 26D, when in fact, it is a 652, brushed chrome over steel, as 626, or US 26D, is a finish code for brushed chrome over bronze or brass. Typically, fire doors of 20 (twenty) minutes or greater cannot be equipped with brass or bronze based hinges, as they will melt too quickly. In actuality, most suppliers are aware that when you call and order a hinge with the lock finish code (626, 613, 612), what you really need is a steel based hinge with the finish to match a bronze or brass based lockset.
Also consider how the door is going to be locked when you are finished. When you install a lockset, the door is locked and controlled by the access control system. If you use electric latch release devices (strikes), you must still, in most instances, replace the entry or passage function lever set to one that has a key and is typically storeroom function. Since you are going to have to remove the lock anyway, you may as well simply drill the door and install an electrified lock. Not only does it cut down on time, but also it will cut your costs by about 30 percent , since you have half as much hardware that the customer must pay for. This makes you more competitive and speeds your job time completion.
After you decide on the type, function, finish, handle style and hinge size needed for your job, you next need to determine how you are going to drill the door for the wire that needs to come from the hinge to the lock opening. While I owned and operated a locksmith business, I would hand-drill doors with a four foot, 3/8 inch diameter alarm installer's drilling bit. However, a number of years ago, I installed two lever locks on two stairwell doors in a small city on the San Francisco Peninsula and the fire marshal would not issue a final permit for the job, since, in his opinion I had voided the fire listing on the doors by modifying them in the field. After a lot of hassle and letters back and forth to and from UL, the fire marshal and the building owner, I finally resolved the situation and the client could occupy the building.