Keypad encoders
A keypad encoder (also called a code lock or PIN pad) is a wall-mounted device that authenticates a user by a secret PIN code. The user types the code on the keypad; if it matches a stored credential, the device sends an output signal — typically closing a relay or pulsing a Wiegand line — to release an electric strike or electronic lock on the door.
HDWR keypad encoders are available in two main variants:
- PIN-only — authentication by numeric code alone; the simplest and most affordable option
- PIN + RFID — combined keypad and proximity reader in one unit; the user can authenticate with a card/fob, a PIN, or both (two-factor mode)
Some models also integrate a fingerprint reader, adding a third authentication factor without requiring a separate biometric device.
Where to use a keypad encoder
- Single-door entry — offices, server rooms, storage areas where you want code-based access without issuing physical keys
- Exit control — mounted on the inside of a door to require a code before leaving (secure areas, laboratories)
- Two-factor checkpoints — high-security zones requiring both a card and a PIN; one combined unit handles both
- Outdoor installations — IP65-rated models for gates, car parks and building entrances exposed to weather
Key specifications to check
| Parameter | What to look for |
|---|---|
| Authentication | PIN only / PIN + RFID / PIN + RFID + fingerprint |
| RFID frequency | 125 kHz (EM4100) or 13.56 MHz (MIFARE) — must match your cards |
| Output interface | Relay (dry contact), Wiegand 26, Wiegand 34 |
| Power supply | 12 V DC (most models) |
| Ingress protection | IP65 for outdoor / wet areas; IP54 for sheltered indoor use |
| Tamper alarm | Output that fires if the device is prised from the wall |
Wiring and output modes
Most HDWR keypad encoders provide at least one relay output (a pair of NO/NC contacts) that can be wired directly to an electric strike or electronic lock. When the user authenticates successfully, the relay closes (or opens, depending on configuration) for a set pulse duration — typically 2–5 seconds — then resets.
On models with Wiegand output, the encoder acts as a standard Wiegand reader toward an access control panel: the panel receives the entered PIN or the RFID card number as a Wiegand 26 or Wiegand 34 data stream and makes the access decision itself.
Keypad encoders FAQ
What is a keypad encoder and how does it work?
A keypad encoder is a wall-mounted unit with a numeric keypad (and often an integrated RFID reader) that verifies the user's identity before releasing a door lock. The user types a PIN code, presents a card or fob, or both. If the credential matches a stored authorisation, the encoder pulses its relay output — or sends a Wiegand signal to a panel — to release the connected electric strike or electronic lock for a configurable dwell time (typically 2–5 seconds).
What is the difference between a PIN-only encoder and a combined PIN + RFID encoder?
A PIN-only encoder authenticates purely by numeric code — no card is needed. A combined PIN + RFID unit adds a proximity reader so the user can authenticate with either a card/fob or a PIN, or you can configure it to require both (two-factor mode). The combined model costs slightly more but eliminates the need to issue and manage physical cards when a code is sufficient, while still supporting cards when needed.
How many PIN codes can I store?
Capacity varies by model. Entry-level HDWR encoders store 10–100 user codes. Mid-range models support 500–2000 codes. The number of codes you need depends on the number of users: for a small office 10–50 codes are usually enough; for a larger site with many staff choose a model with at least 500 slots. The administrator (master) code is always separate from user codes and has higher privileges such as adding and deleting users and changing settings.
How do I add and delete user PIN codes?
The exact procedure varies by model and is documented in the product manual. The general process is: (1) enter programming mode using the administrator (master) code; (2) select the operation — add user, delete user, or change code; (3) enter the slot number and the new PIN; (4) confirm and exit programming mode. Some models support a management software or RS485 bus for bulk provisioning. Always change the factory default administrator code during the initial setup.
Can the keypad be used outdoors?
Yes — look for models rated IP65 or better. IP65 means the device is completely dust-tight and protected against low-pressure water jets from any direction, making it suitable for outdoor gates, covered entrances, and car parks. For sheltered indoor locations (corridor walls, covered porches) IP54 is sufficient. Avoid using an indoor-only (non-IP-rated) keypad in damp or dusty environments — corrosion and keypad failure will follow.
What RFID frequency does the combined keypad + RFID encoder support?
Most HDWR combined encoders support either 125 kHz (compatible with EM4100 and Unique cards and fobs) or 13.56 MHz (compatible with MIFARE Classic, MIFARE Plus, and ISO 14443 / ISO 15693 cards). A small number of models are dual-frequency. You must match the encoder's frequency to the cards or fobs you intend to use — a 125 kHz encoder will not read 13.56 MHz MIFARE cards, and vice versa. Check the specification of both the encoder and the cards before ordering.
How is the keypad encoder wired to the door lock?
A typical single-door wiring uses three connections: (1) power — 12 V DC and GND from the power supply to the encoder; (2) lock power — 12 V DC from the power supply to the electric strike or lock; (3) trigger — the encoder's relay NO (normally-open) output wired in series with the lock's power line, or the encoder's relay COM and NO wired to the lock's trigger terminals. When the relay closes on successful authentication, current flows through the lock and it releases. The exit button (inside the door) is wired in parallel with the relay output.
What does the Wiegand output on a keypad encoder do?
When a keypad encoder has a Wiegand output, it behaves as a standard access control reader toward a panel or controller: successful PIN entry or card presentation sends the credential as a Wiegand 26 or Wiegand 34 bit stream over the DATA0 and DATA1 lines to the panel. The panel then makes the access decision and controls the lock directly. This is useful when you have a multi-door installation managed by a central controller, rather than each encoder controlling its lock independently.