VT825DC / Telecom Monitoring unit (legacy)

Owned by Vladimir Tayzhev
Last updated: Oct 27, 2022
3 min read

  End of Life: 31.12.2022


Product page: https://vutlan.com/remote-monitoring-units/93-vt825dc-monitoring-unit-with-dc-power-supply.html



1. "CAN" - digital connector RJ12 for the connection of CAN sensors and CAN extensions on a CAN bus, with auto-sensing.

2. "SD" - SD, MicroSD card connector with ejector, needed to store data.

3. "Main ANTENNA" - connector, used when LTE modem is installed inside of the appliance to connect the antenna. (LTE modems are ordered separately)

4. "Modem Status" - indicates LTE modem status.

5a. "1-WIRE" - Used when the “VT10 / 1-Wire module” (extension board ordered separately) is installed inside. A serial communication protocol that uses a single data line plus ground reference between master (VT825/ Monitoring unit) and 1-Wire slave device.

5b. “1-WIRE STATUS” - If the green light is “ON”, then the 1-Wire module is on. There’s an element inside the monitoring unit’s interface that can be switched “ON” and “OFF”, which activates the 1-Wire bus.

6. LEDs: "ACT" - indicates appliance status, "E1" - indicates 12V E1 relay status, "E2" - indicates 12V E2 relay status, "ERROR" - indicates error and traffic.

• Blinking "ACT" ............ • Blinking "E1" ............ • Blinking "E2"............ • Blinking "ERROR" ..........

7. "LAN" - Ethernet 10/100 Base-T port, provides an Ethernet connection.

• LEDs - "yellow" (status) and "green" (traffic) show the network traffic. The status LED: flashes green when the system starts up and shows the connection state (constant green light - the connection is established, blinking green - the connection attempt).

8. "USB" - type miniAB USB-port 2.0, required to connect a USB camera or to restore an appliance.

9. "RESTART" or "RESET" - restarts the appliance.

10. LED: "CAN" - indicates CAN bus status.

"CAN" blinks slowly - nothing is connected

"CAN" blinks fast - configuration is in process

"CAN" glows constantly - connected to CAN devices

11. "A1..A8" - 8 RJ12 analog sensor inputs with auto-sensing.

12. "VT18 / Extension board" - (ordered separately) consists of:

  12a. LEDs: "Relays 1, 2" - indicates power relays status.

  12b. "DC 12V" - power backup terminal.

  12c. "Relays 1, 2" - relais power terminals.

  12d. "DRY CONTACTS 5...12" - Dry contacts terminal (type IN)

13 "DC power" - power input. Please specify 24VDC or 48VDC needed during the order.

15. "VT101 / Battery holder" - ordered separately.

16. "" - External chassis grounding, M4 thread.

17. "Dip switch" Normal ↑ Off - the system should be always switched to this mode.

Recovery ↓ On - use this option only in case you need to recover manufacturing settings.

18. "TEMPERATURE SENSOR" - accuracy +/- 1 °C.

19. "SIM" - connector with an ejector is used when the modem is installed inside of the appliance.

20. "DRY CONTACTS 1...4" - Dry contacts terminal (type IN)

21. "OUTPUT 12V 0.25A" - 12V 0.25A output electronic relay teminal



Developer notes: v2.5, September 2020