Glossary
What the words on a lock box and a spec sheet mean. General definitions, so you can compare any smart lock with confidence.
A
- Access sharing
- Giving another person permission to open a lock, usually through an app. The owner can normally set who gets access and remove it again. See: Short-stay hosts
- ANSI/BHMA grade
- A North American performance grade for locks and door hardware, tested for cycles, strength and security. Grade 1 is the toughest. It matters mostly for products sold in the US and Canada.
- Auto-lock
- A setting that locks the door again by itself a set time after it closes, so it is never left unlocked by mistake.
- Automation
- A rule that makes a device act on its own, for example turning on a light when the front door unlocks after dark.
B
- Backset
- The distance from the edge of the door to the centre of the lock hole. Common backsets are measured in millimetres and must match the lock body. See: Door fit guide
- Bluetooth lock
- A smart lock that talks to your phone over short-range Bluetooth. It works when you are near the door and needs a gateway or Wi-Fi for remote control.
C
- CE marking
- The mark a manufacturer puts on a product sold in the European Economic Area to declare that it meets EU safety, health and environmental rules, including radio and electrical safety for connected locks. See: Certification
- Contact sensor
- A two-part sensor, one half on the door or window and one on the frame. It reports when the two halves move apart, meaning the door or window has opened. See: Sensors and safety
- Cylinder
- The part of a lock that holds the key mechanism. In many smart locks it stays as a mechanical backup beneath the electronic parts.
D
- Deadbolt
- A solid bolt that slides into the door frame and is moved only by the key or the lock, so it cannot be pushed back like a spring latch.
- Door thickness
- How thick the door leaf is, measured in millimetres. A lock is built for a range of thicknesses, so measure before choosing. See: Door fit guide
E
- Emergency power
- A way to wake a lock whose battery has run flat. Many electronic locks have contacts for a USB-C cable or a 9V battery so you can enter a code or use a fingerprint once more.
- EN 12209
- The European standard for mechanical locks and latches. It tests how long the lock body lasts and how well it resists force.
- EN 1303
- The European standard for lock cylinders. It grades a cylinder on durability, key security and resistance to attack such as drilling.
- EN 14846
- The European standard for electromechanical locks, the motor-driven lock bodies used in many electronic and smart locks.
- Entry log
- A record of when a door was opened and by which method or user. Whether a lock keeps a log depends on the model. See: Gateway and app
- Escutcheon
- The plate that sits on the door face around a handle, keyhole or keypad. It covers the cut-out and holds the lock parts in place.
F
- Face recognition
- Unlocking by matching the face in front of the lock to a face that was enrolled earlier. Locks use a camera or sensor and compare against stored data. See: Technology
- Fail-safe and fail-secure
- Describes what a lock does when power is lost. A fail-safe lock unlocks, which helps escape. A fail-secure lock stays locked, which protects the room. Stand-alone battery locks are a different case: they keep their last state and rely on a mechanical key.
- False acceptance rate
- How often a biometric system wrongly accepts someone who is not enrolled. A lower rate means stricter matching, and it is usually paired with the false rejection rate, which counts genuine users turned away.
- FCC certification
- Approval from the US Federal Communications Commission that a wireless device, such as a Wi-Fi or Bluetooth lock, stays within radio emission limits. It is needed to sell radio devices in the US.
- Fingerprint sensor
- A pad that reads the ridges of a finger and compares them with fingerprints saved earlier. Dry, wet or worn fingers can read less reliably, so most locks offer other ways in. See: Technology
- Fob
- A small keyring tag that holds a chip. Hold it near the lock reader to open the door instead of using a key.
G
- Gateway
- A small device that connects smart locks and sensors to your home Wi-Fi so they can be reached from outside the house. Also called a hub or bridge. See: Meloc Gateway
H
- Handing
- Which side a door hinges on, described as left-hand or right-hand. Many handled locks must be set to match the door, and some can be reversed. See: Door fit guide
- Hub
- Another name for a gateway: the central device smart home products connect to. See Gateway. See: Meloc Gateway
I
- Intercom
- A system that lets you speak to a visitor at the entrance from inside. Video versions add a screen at a wall panel or on your phone. See: Entry and cameras
- IP rating
- A two-digit code for dust and water protection, such as IP65. The first digit covers solids and the second covers liquids. A higher number means more protection, and it is a lab test result, not a promise for every condition.
L
- Latch
- A spring bolt that holds the door closed. It is pushed back when you turn a handle and springs out again when the door shuts.
- Lever handle and knob
- The two common handle shapes. A lever is pressed down and is easier with full hands or limited grip. A knob is turned. See: Interior family
- Liveness detection
- A check that the face or finger is from a live person and not a photo, video or copy. It makes recognition harder to fool.
M
- Mechanical override key
- A physical key kept as a backup. It opens the lock if the battery is flat or the electronics fail. See: Power and backup
- Mortise lock
- A lock body that sits inside a rectangular pocket cut into the edge of the door. Mortise locks are common on solid and heavy doors. See: Door fit guide
- Motion sensor
- A sensor that detects movement, often with infrared. It can trigger a light, an alert or a scene. See: Sensors and safety
N
- NFC card
- A card with a short-range chip. Tap it on the lock reader to open the door. NFC and RFID cards work on the same idea of a chip read at close range.
O
- One-time code
- A passcode that works once, or for a limited period, and then stops. Hosts use it for a single delivery or visit. See: Short-stay hosts
P
- Passage mode
- A setting that keeps the door unlocked so people can walk through without a code. It suits busy hours in a shop or office and should be switched off afterwards. See: Offices and shops
- PIN code
- A number entered on a keypad to open the lock. Longer codes are harder to guess, and codes should be changed when a person no longer needs access.
R
- RFID card
- A card with a radio chip that a reader detects at short range. Lost cards can usually be removed from the lock so they stop working.
- RoHS
- An EU directive that limits hazardous substances, such as lead and mercury, in electrical and electronic products. See: Certification
S
- Scramble code
- A way to hide a PIN by typing extra random digits before or after it. Anyone watching or reading smudges on the pad cannot tell which digits are real.
- Slim lock
- A narrow lock designed for aluminium and glass doors, which have thin frames and no space for a large body. See: Slim family
- Smart scene
- A saved group of actions that run together with one tap or trigger, such as locking the door, turning lights off and arming a sensor when you leave.
T
- TTLock
- A smart lock app and platform used by many lock makers, mainly for Bluetooth locks, with optional remote access through a gateway. Keep it updated, because updates carry security fixes.
- Tuya Smart
- A cloud platform and app used by many makers of connected devices, so products from different brands can sit in one app. Always check which app a lock uses before you buy.
- Two-way audio
- Speaking and listening through a doorbell, camera or intercom, so you can talk to a visitor from your phone or a wall panel. See: Entry and cameras
V
- Video doorbell
- A doorbell with a camera. It sends an alert to your phone when someone presses it or arrives, so you can see and speak to the visitor. See: Entry and cameras
W
- Wi-Fi lock
- A smart lock that joins your home network directly, so you can control it from anywhere without a separate gateway. It generally uses more battery than a Bluetooth lock.
Z
- Zigbee
- A low-power wireless standard for small smart home devices. Zigbee devices link through a hub and form a mesh, passing messages between each other.
Still unsure about your door?
Tell our team about the door and the household, and we will point you to the right lock.
Definitions are general guidance and do not describe a specific product. For Meloc models see Locks, Technology and Business.
Smart locks