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1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errorsESP-RFID can trigger an electric lock through a separate Shelly or Tasmota relay: after an authorized card scan or PIN, ESP-RFID publishes a message over MQTT, and the relay switches the lock for a configured interval. This keeps the lock actuator separate from the reader/controller, but it does not make the DIY system security-certified. ESP-RFID warns that its UID-based identification is hobby grade and unsuitable where strong security is required.
How ESP-RFID controls an external relay
The external-relay arrangement separates credential handling from lock switching. ESP-RFID decides whether a card or PIN is authorized; MQTT carries the resulting command to the relay device. A broker is the message intermediary, so ESP-RFID and the relay must be configured to communicate through the same broker and corresponding topic/message settings.
- Read and authorize: ESP-RFID stores user information and evaluates a scanned credential or entered PIN.
- Publish: On an authorized event, it sends the configured lock topic and message over MQTT.
- Switch: The broker delivers the message to a separate Shelly or suitable Tasmota relay.
- Release: The relay energizes the lock, then turns off according to its configured auto-off interval. The walkthrough uses a pulse of a few seconds as an example; the correct interval depends on the lock and installation.
The Hackster walkthrough demonstrates the pattern with a Shelly 1, while ESP-RFID documents MQTT integration and Tasmota supports MQTT control. See the ESP-RFID/Shelly walkthrough, the ESP-RFID project README, and Tasmota MQTT documentation.
What hardware and compatibility to check
The walkthrough’s example uses an ESP-RFID board (with or without its onboard relay), a Shelly 1, two 12 VDC supplies, a Wiegand RFID reader, a 12 VDC/12 VAC fail-secure electric strike, and a 125 kHz card. Treat this as one example, not a universal parts list: confirm every component against the exact lock, reader and relay documentation before buying or wiring.
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| Check | Why it matters |
|---|---|
| Reader technology and credential format | ESP-RFID documents MFRC522, PN532, RDM6300 and Wiegand reader paths. Its README recommends MIFARE Classic 1KB PICCs, while the walkthrough’s 125 kHz example is a different hardware context. A 125 kHz card will not necessarily work with every reader, and Wiegand readers do not all accept the same credential formats. Match the reader and card/tag specifications. |
| Lock voltage, current and behavior | Check the lock’s actual voltage and current requirements, and whether it is fail-secure or fail-safe. The walkthrough includes a fail-secure strike; do not assume that choice fits your door or safety requirements. |
| Relay contacts and isolation | Verify contact ratings and whether the relay switches the lock’s supply directly or through an appropriate isolated arrangement. The walkthrough says another relay board may be used if it has clear MQTT control and auto-off, and flags 12 VDC operation or isolated relay switching as selection constraints. |
| Power arrangement | Check the required supplies and wiring for the controller, relay and lock together. The walkthrough lists two 12 VDC supplies; do not infer that this arrangement suits different hardware. |
| Controller board | The walkthrough says the ESP-RFID board without a relay can also be used when switching is delegated externally. The project README describes an official board designed for a single 12 V supply and hardware options. Board availability can change; the project points to its Tindie store. |
For Shelly hardware, use documentation specific to the exact model and electrical configuration. Tasmota’s Shelly 2.5 documentation says that model is supported from Tasmota 6.5.0.8 using a template. It also warns not to connect anything to the device GPIOs because they are connected to AC power. That warning is specific and important: do not treat a Shelly 2.5 as a low-voltage GPIO accessory.
Configuration and commissioning
The project documentation establishes MQTT integration, and the walkthrough explains the external-relay approach, but the exact interface labels and setup steps depend on ESP-RFID firmware, broker configuration and relay model. Use the current documentation for those devices rather than copying settings intended for a different version.
Rank #2
- ✔Based on ESP-01S WIFI module.
- ✔Designed for smart home,internet and other DIY projects.
- ✔With this smart relay, you will easy to DIY your smart switch to control any device by your phone anywhere.Providing APP and LUA source programs. It can be controlled remotely
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- Confirm that the reader and credentials match in technology and format, and that the lock’s voltage, current and operating behavior are known.
- Set up an MQTT broker reachable by both ESP-RFID and the relay. Configure the ESP-RFID lock topic/message and the relay’s MQTT subscription/control to match.
- Configure the relay’s auto-off behavior to provide the lock pulse required by the specific installation; do not treat the walkthrough’s few-second example as a lock specification.
- With the door secured and the lock circuit handled safely, test an authorized credential and verify that the relay switches and returns off as intended. Also verify that unauthorized credentials do not trigger the lock.
Security and operational limitations
ESP-RFID’s README says the system currently identifies users by tag UID and notes that some PICCs allow their UIDs to be manually set. The project cautions that software bugs or network attacks could result in unauthorized access and explicitly describes itself as a hobby-grade project, not suitable where strong security is needed. Moving the relay away from the reader may separate the actuator physically, but it does not remove credential or network risks.
- The project suggests disabling Wi-Fi to reduce attack surface and setting a strong web UI password. Consider how those choices affect management and connectivity in your installation.
- ESP-RFID can synchronize time using NTP in client mode, which requires internet access, or run in access-point mode with manually synchronized time. The project cautions that time can drift.
- The README reports a test in which a WeMos D1 mini handled at least 1,000 unique users. This is a project-reported capacity test, not evidence of security, long-term reliability or suitability for production access control.
When this arrangement makes sense
Use an external MQTT relay when the design calls for the ESP-RFID controller to authorize credentials while a separate device switches the lock, and when you can validate the MQTT path, electrical ratings and installation-specific lock behavior. Choose the reader and credential together, verify the exact relay model and wiring documentation, and do not rely on this hobby project for locations that require strong, certified access control.
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- : The relay board is equipped with and BLE modules
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