U
Underwriters Laboratories, Inc. (UL)
An agency that tests and lists various consumer products for safety and reliability that operates in the United States. Most alarm system products are UL-listed for use in various applications.
Underwriters Laboratories Canada (ULC)
An agency that tests and lists various consumer products for safety and reliability that operates in Canada. Some alarm system products are ULC listed for use in various applications.
UL Certificate
A certificate issued by Underwriters Laboratories Inc. that serves as evidence that an alarm system meets UL requirements for installation, operation and maintenance.
ULC Certificate
A certificate issued by Underwriters Laboratories Canada that serves as evidence that an alarm system meets ULC requirements for installation, operation and maintenance.
UL Listed
Signifies that production samples of the product have been found to comply with established UL requirements and that the manufacturer is authorized to use the UL listing marks on the specific products complying with the requirements. UL Listings also require follow-up services to ensure compliance.
ULC Listed
Signifies that production samples of the product have been found to comply with established ULC requirements and that the manufacturer is authorized to use the ULC listing marks on the specific products complying with the requirements. ULC Listings also require follow-up services to ensure compliance.
Uninterruptible Power Supply (UPS)
A device that provides continuous power conditioning to an AC line within prescribed plus or minus tolerances. A UPS protects against over voltage conditions, brownouts, and provides standby power to allow for an orderly shutdown when primary power fails.
User
A person authorized to operate all or part of the security or fire system.
User Code
A 3- to 12-digit number programmed into the panel and assigned to a user that allows them to access its functions. User codes are typically assigned authority levels that restrict the user to one or more of the system’s functions or to certain areas for arming and disarming or door access.
User Datagram Protocol (UDP)
A connectionless protocol that, like TCP, runs on top of IP networks. Unlike TCP/IP, UDP/IP provides very few error recovery services. Instead, it offers a direct way to send and receive datagrams over an IP network. This is used primarily for broadcasting messages over a network.
User Error
The number one cause of false alarms. A user who does not know how to perform a function they have access to, or who has not been trained properly in the system operation. User error can and will cause false alarms. It is important that all new users receive instruction on arming/disarming routines and alarm cancellation procedures to lessen the incidents of false alarms.
User Menu
A keypad feature that provides a list of optional functions a user can access. These functions include sensor reset, door access, outputs on/off, system status, and user codes. Individual user menu items are displayed to persons according to the authority level of the user code they entered to access the menu.
User Profile
A group of specific activities or actions, authority levels, and area access capabilities assigned to a system user.
Utility Software
Programs that make operation of a PC or LAN more convenient, including programs to move disk files more easily and diagnostic programs.