The Industrial IP & 4G Smart Relay is a 9–36 V DC, DIN-rail control module for electrical cabinets. It switches a power relay from the onboard web UI, SMS or MQTT over Ethernet and 4G. When a camera, router or modem freezes, ICMP ping detects the stall and the relay power-cycles the load. One jumper-selectable universal input reads dry contact, 0–10 V, 4–20 mA or NTC; RS485 listens to Modbus RTU devices.
One board, several field jobs — not a product family. Typical work: reset a locked IP camera, watch panel or cold-room temperature with NTC, turn a float / dry-contact alarm into SMS, or read a meter on RS485 and publish MQTT. PCB design and firmware sit on the same card, so a PLC + GSM modem + I/O stack is usually unnecessary. The engineering line matches What We Do.
On boot the module joins the LAN through Ethernet (W5500, 10/100). The WebUI opens at the device IP: relay state, ping targets, SMS numbers and MQTT broker. If Ethernet drops, 4G LTE Cat-1 (A7670E) is the backup path — there is no “always online” claim; delay depends on the cell network and SIM plan. The IP watchdog pings a host; after N misses it runs an on/off cycle, waits, then pings again. A frozen source device can recover without a site visit.
| Supply | 9–36 V DC |
|---|---|
| Relay | 1× NO/NC, 250 V AC / 10 A |
| Input | 1× universal (contact / 0–10 V / 4–20 mA / NTC) |
| Comms | Ethernet 10/100, 4G LTE Cat-1, RS485, SMS, MQTT |
| Ethernet PHY | WIZnet W5500 |
| Cellular modem | A7670E |
| Mounting | DIN rail / cabinet |
| Environment | Industrial cabinet; antenna may exit the metal box |
The 10 A contact is rated for ohmic load up to the thermal limit. Do not drive a compressor, fan motor or servo drive from this contact; put a contactor (and a soft starter if needed) in between. The 4–20 mA loop needs an external transmitter; the board does not source 24 V loop power. NTC curves are selected in the WebUI; raw resistance can ride in the MQTT payload.
Feed the module from the cabinet 24 V DC rail and respect terminal polarity. Ethernet goes to the switch; keep the SMA antenna outside a metal enclosure when possible. Fit a 4G SIM with SMS quota and set the operator APN. Point the watchdog at the camera management IP, not a random host. Test the relay unloaded, then onto the contactor coil. Remote reset does not replace a safety relay or e-stop chain on site.
A panel-mount relay and I/O module with Ethernet and 4G. It offers remote power control via web UI, SMS and MQTT, ping-based auto reset and one universal analogue/digital input.
The unit pings a configured IP. After consecutive misses it cuts and restores supply. Cycle count and wait time are limited in the WebUI so it cannot run an endless reset loop.
4G takes over as backup. SMS and MQTT try to continue on cellular data. Without coverage, commands are delayed and the event is logged.
No. The 10 A contact is for ohmic load and contactor coils. Run motors, heater banks or inverter inputs through a contactor or SSR.
WebUI (HTTP), SMS, MQTT/JSON and Modbus RTU on RS485. OPC UA and BACnet are not on this board; bridge them on the server if needed.
Contact Revan Technology for a quote and cabinet layout. Dimensions, terminal map and a sample WebUI screen are shared in the project pack.