# Access control module, NFC, RFID and Fingerprint, 2 channels, 10-120VDC

> Access control module with authentication via fingerprint, 13.56MHz IC card or NFC phone (ref. 88041). Powered by 10-120VDC, stores 100 cards and 50 fingerprints, 2 integrated relays with support for an optional third relay. Offers 10 configurable operating modes, programmable activation times and a 3V auxiliary output. The fingerprint reader has a resolution of 120x120 and is not water resistant.

- Page: https://sigmanortec.ro/en/access-control-module-nfc-rfid-and-fingerprint-2-channels-10-120vdc
- Price: 297.58 RON
- Availability: In stock; 1-2 zile
- Reference: 88041 · EAN: 5948447589854
- Category: Electronic components > Access Control
- Specifications: Supply Voltage: 10; Maximum Input Voltage: 120; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.
- Package (shipping data): 0.156 kg
- Updated: 2026-10-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 02:22 (Europe/Bucharest)

## Description

Flexible solution for access control and automation, with authentication by fingerprint, 13.56MHz IC card or NFC phone. Operates at 10-120VDC, stores up to 100 cards and 50 fingerprints, includes 2 relays for controlling gates, doors, electronic projects or automotive applications, with 10 configurable modes and programmable activation times.
The D231 access control module combines three authentication methods on the same board: fingerprint, 13.56 MHz IC card, and NFC phone, for secure control of electric locks, doors, and gates. It is also suitable for car modifications, forklifts, electric bicycles, scooters, and motorcycles, or for any electronic project that requires secure activation without a mechanical key and without complicated wiring.
The module reads IC cards at 13.56 MHz and recognizes fingerprints through the dedicated reader, and its memory stores up to 100 fingerprints, of which a maximum of 10 are administrator fingerprints, one administrator card, and up to 1999 user cards or phones. All data remains saved even after power loss. The power supply accepts any DC voltage between 10 and 120 VDC, which allows direct connection to batteries and 12 V, 24 V, 48 V, 60 V, 72 V, or 96 V systems without an additional converter. The board offers 11 operating modes, selectable from the setting button, covering pulse control, latching, or both relays simultaneously, depending on the user type and authentication method.
Among the main features are the two integrated 10 A relays with NO, NC, and COM dry contacts, the output for an optional third relay, the controlled 3 V output for powering a car remote, and the input for a mechanical button that activates the relays without verification. Power is supplied directly to the Power input terminals, with a DC voltage between 10 and 120 VDC.
Because the contacts of the two relays are potential-free, dry contacts, the module can also be integrated into a system with Arduino, ESP32, STM32, Raspberry Pi, or other compatible platforms, with the contacts used as a galvanically isolated input. NFC phones work through a card added in the Wallet app; generic NFC apps cannot be used for unlocking.
Specifications:
Power supply voltage: 10 - 120 VDC
Maximum relay load current: 10 A
Model: D231
Card reading frequency: 13.56 MHz
Authentication methods: Fingerprint, IC card, NFC phone
Fingerprint capacity: 100 with the standard reader, of which a maximum of 10 are administrator fingerprints
Administrator card: 1
User card capacity: 1999
Data retention after power loss: Yes
Integrated relays: 2, type SRD-05VDC-SL-C
Relay contacts: NO, NC, COM, dry contact
Relay ratings: 10 A 250 VAC, 10 A 30 VDC
Optional relay: Output for Relay 3, not included
Auxiliary output: Controlled 3 V
Button input: Yes, unlock without verification
Operating modes: 11, default mode 3
Relay pulse time: 0.3 s - 15 minutes, default 0.5 s
Relay 1 delay in modes 1, 8, 9, and 10: 0 - 3 s, default 1 s
Phone compatibility: Android and iPhone with NFC, via a card added in the Wallet app
Fingerprint sensor: Not waterproof
Fingerprint reader diameter: 21 mm
Main board dimensions: 67.3 x 52 x 19.2 mm
Antenna board dimensions: 45.5 x 22.3 x 6.5 mm
Antenna box dimensions: 48 x 26 x 15 mm
Dimensions: 82 x 57 x 34 mm
Pinout:
Connector
Pin
Function
Power input
+
Positive power supply, 10 - 120 VDC
Power input
Negative power supply, ground
RELAY 1
COM1
Relay 1 common
RELAY 1
NO1
Relay 1 normally open contact
RELAY 1
NC1
Relay 1 normally closed contact
RELAY 2
COM2
Relay 2 common
RELAY 2
NO2
Relay 2 normally open contact
RELAY 2
NC2
Relay 2 normally closed contact
3V output
3V+
Controlled 3 V output, positive
3V output
3V-
Controlled 3 V output, ground
Optional relay 3
Connector for optional relay 3, not included
Fingerprint head
6 pins
Fingerprint reader connector
NFC
NFC / RFID antenna connector
Button
Mechanical button input, unlock without verification
Communication port
5 pins
Expansion / communication port
Setting key
Mode setting button
Mode
LED indication
Operation
1
1 blink
Car door 1. Upon unlocking, the 3V output is activated; after 1 s Relay 1 closes for 0.5 s and Relay 3 engages. The second unlock closes Relay 2 for 0.5 s, and after 5 s the 3V output is deactivated and Relay 3 disengages
2
2 blinks
Start with one button 1. The first unlock engages Relay 1; a subsequent failed verification disengages it. A new successful unlock also engages Relay 2, which disengages immediately when the finger or card is removed. A new verification disengages Relay 1
3
3 blinks
Default, lock and seat. Unlocking engages Relay 1; the next unlock disengages it. If the finger or card is held for about 2 s after unlocking, Relay 2 closes for 0.5 s
4
4 blinks
Lock, seat, and optional trunk. The administrator card or fingerprint engages Relay 1; the next unlock disengages it. If held for about 2 s, Relay 2 closes for 0.5 s. The user fingerprint closes Relay 3 for 0.5 s, regardless of Relay 1 state
5
5 blinks
Lock, headlights, and optional seat. The administrator engages Relay 1; the next unlock disengages Relay 1 and Relay 2. If held for about 2 s, Relay 2 engages; the next unlock disengages both relays. The user fingerprint closes Relay 3 for 0.5 s, regardless of Relay 1 state
6
6 blinks
Double pulse. Any unlock closes Relay 1 and Relay 2 simultaneously for 0.5 s
7
7 blinks
Double latching. The first unlock engages Relay 1 and Relay 2 simultaneously; the second unlock disengages them
8
8 blinks
Car door 2 and trunk. Upon unlocking, the 3V output is activated; after 1 s Relay 1 closes for 0.5 s. The second unlock closes Relay 2 for 0.5 s, and the 3V output is deactivated after 5 s. If the finger or card is held for 3 s, Relay 3 engages until removal
9
9 blinks
Car door 3. The administrator activates the 3V output; after 1 s Relay 1 closes for 0.5 s and Relay 3 engages. The user closes Relay 2 for 0.5 s; after 5 s the 3V output is deactivated and Relay 3 disengages
10
10 blinks
Three separate relays. The administrator activates the 3V output; after 1 s Relay 1 closes for 0.5 s. The user card closes Relay 2 for 0.5 s; the 3V output is deactivated after 5 s. The user fingerprint closes Relay 3 for 0.5 s
11
11 blinks
Start with one button 2. Unlocking engages Relay 1. If the finger or card is held for another 1 s, Relay 2 also engages, and it disengages immediately upon removal. A new verification disengages Relay 1
Usage:
Connect the fingerprint reader to the Fingerprint head connector and the NFC / RFID antenna to the NFC connector.
Power the board at the Power input terminals, observing polarity, with a DC voltage between 10 and 120 VDC; check the power supply voltage in advance so as not to exceed this range.
Note that the relays do not provide their own voltage; their contacts are dry contacts. To power a load, connect the positive from the power supply to COM1 or COM2 and the load to NO1 or NO2; normally only the NO and COM contacts are used.
With the board powered, press the setting button; the blue LED blinks as many times as the active mode number. Each press advances to the next mode from 1 to 11, and the selected mode is saved automatically. The factory default mode is mode 3.
Keep in mind that, from the factory and after reset, the module is in demonstration mode, in which any fingerprint or IC card controls the relay. Register the administrator fingerprint and card immediately after installation, before granting access to other users.
For an electric bicycle or motorcycle, in mode 3, connect the battery positive to Power input + and, through a separate wire, to COM1, and connect NO1 to the ACC wire of the ignition switch. For a 12 V seat lock, connect COM2 to the 12V+ from the vehicle's 12 V converter, NO2 to the lock, and the other wire of the lock to GND.
For starting a car or forklift, in mode 2 or 11, connect the permanent positive to Power input + and, through separate wires, to COM1 and COM2, then NO1 to the ACC / ON line, and NO2 to the starter line.