Honeywell 7939WG Frequently Asked Questions

What Is the Best Alarm Contact?
There is no single best alarm contact. Many different types of door and window contacts are available, and the best one depends on the needs of the user. There are several questions to ask when looking for an alarm contact so that you can obtain the perfect one. Learn more about alarm contacts.
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What Do Normally Closed and Normally Open Mean?
"Normal" is the normal state of an opening, such as a door. Normally open/closed refers to the state of a contact connected to a door in its normal position.
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Honeywell Glassbreak vs Window Sensors
Glass break detectors and windows sensors are both used to protect against a break-in through a window, but they work in very differnet ways.
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