Page 15 - Security Today, October 2020
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“It is incumbent upon each of us to be informed of the latest initiatives and to actively participate in the adoption of practical new solutions that provide better health protection to building occupants.”
By David Price
cally assume that a device is wireless. Al- though this is true in most cases, some man- ufacturers do also offer a battery-operated touchless switch with a wired relay contact. This switch design is ideal for replacing a non-powered manual switch with a sensor switch in a matter of minutes.
The selection of a smart touchless switch is also an important consideration. A smart switch has inputs for a REX de- tector/switch and door contact (required for restroom control and other door con- trol applications). Smart switch function- ality can save the installer hundreds of dollars by avoiding unnecessary equip- ment costs and installation labor.
Another important consideration is the decision to select a hard-wired touch- less switch vs. a wireless switch. Wireless touchless switches provide cost savings on virtually any project but provide the great- est benefit when running wireless is time consuming or impractical.
Request-to-Exit Detectors
Passive infrared REX detectors are specialized motion detectors that are typi- cally used to shunt an access control alarm when a building occupant exits a door. They’re also able to facilitate door auto- mation in a range of other applications.
REX detectors are designed to oper- ate differently from PIR motion detectors used as part of an intrusion alarm system. The detection pattern is ‘targeted’ and eas- ily directed with mechanical dampers, and the more advanced models on the market offer a number of value added features not found in ‘basic’ REX detector models.
Wireless Handheld Fobs
An alternative to installing a sensor de- vice that will enable a door to open auto- matically is to provide each building occu- pant with a manual activation device that only they will use. The most common of these devices is a wireless key fob.
There are two types of receivers used in wireless systems; secure Wiegand wire- less receivers that are used in access con- trol systems, and non-secure relay output receivers used for general door activation.
best solutions now being deployed were actually developed long before the COV- ID-19 pandemic occurred. Industry manu- facturers, such as Camden Door Controls, have invested heavily in no-touch technol- ogy, including motion sensors and wireless systems. This was partly to serve specialty applications, such as switches to eliminate
germs in operating rooms, but also to pro- vide the added benefits of much greater convenience for all building occupants, as well as enhanced ADA compliance for persons with disabilities.
The review of no-touch and low-touch solutions below will provide a quick guide to “best practices” for eliminating the spread of germs in public buildings, in- cluding activation devices installed on en- trance and egress doors, washroom doors and interior partition doors.
Touchless Switches
The use of touchless switches (also re- ferred to as “no-touch” or “hands-free” switches) to activate automatic door op- erators or de-energize locking devices is increasing at an unprecedented rate. It’s very likely that touchless switches could become more common than push plate switches in the not too distant future.
There are several different sensor tech- nologies being offered by touchless switch manufacturers, including microwave and capacitive sensors, but the most common technology is active infrared. This tech- nology has proven to be the best choice due to a low manufacturing cost, easy ad- justability and a high degree of reliability across all applications.
This is not to say that all infrared touchless switches are created equal. There are important differences in switch design, features, and performance that system specifiers and installers need to know before selecting the switch that is best for their application.
Let’s start with the design of the infra- red sensor itself. Having the lowest current draw means saving energy over the life of the switch but it will also enable battery operated models to last a long time. This is why Cam- den Door Controls developed infrared ‘mi- cro-burst’ technology. This patented design greatly reduces the power requirement of the switch (by cycling and minimizing power to the switch sensor) and allows ‘SureWaveTM battery powered touchless switches to last up to two years with common alkaline batteries, and up to four years using lithium batteries.
When we think of battery life, we typi-
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