CAN devices connection

This section includes child pages:

CAN sensors and CAN units connection

  1. Connect CAN devices to any port CAN1 or CAN2 on the monitoring system using a cable supplied. CAN sensors can also be connected to the port of another CAN sensor or CAN unit that is connected to the CAN bus. Determination of the devices and their connection is done through a web interface.


You can connect up to x32 CAN units in a CAN bus chain.

  1. The TR should be "ON" for the last sensor on each bus "CAN 1" and "CAN 2". See section "TR" below.

This procedure applies to the following sensors, which are supported by the appliance and are connected to the CAN ports:

CAN sensors, and modules:

CAN extensions:


Read more about Setting up CAN sensors.

CAN cable and limited line length

The maximum length of the CAN line in Vutlan monitoring systems is 225 m due to limitations on the ohmic resistance of cables with RJ12 connectors.

Vutlan AWG24 cables have low resistance.

Since the conductivity of aluminum is much lower than that of copper, the resistance of CCA cables is much higher than that of pure copper cables of the same size.

It is advisable to use two or three pairs of cables such as UTP Cat3.5.6 with 24AWG with a copper core. It is possible to use a 4-wire or 6-wire TRONIC or UTP CCA cable, but the maximum CAN line length will be reduced.

TR termination switch

pic.1.1: FR is OFF, TR is ON.                    pic.1.2: FR is OFF, TR is OFF.

Adding CAN modules and sensors

To connect the CAN module or CAN sensor to the CAN bus of the system, go to the interface >> CAN configuration panel >> Select the CAN1 or CAN2 tab (select the connected physical CAN1 or CAN2 port on the master module).

Click the "Configure" button and wait. The system will start CAN bus polling, soon it will display the data lines and write “Done!”. The modules and sensors connected to the CAN input will appear in a tab in the list. Click the Apply button and then Restart.

The green LED "CAN status" of the device will light up.

Go to the panel "System Tree" to see the new devices or new sensors. The article numbers for CAN devices are VT4xx. If they do not appear, wait, or refresh.


CAN sensors have LEDs that indicate the following states:

  • Red continuous light, green flickers - no communication with the master module

  • Red continuous light, green is off - there is a connection with the master unit but is not included in the monitoring system (not configured)

  • Red is off, Green continuously light - work as part of a monitoring system

  • All LEDs are off: no power or sensor is defective.

Maximum cable length test














Sensor extension unit









Rack control unit






Dry contacts unit






Smoke, humidity, temperature





VT490 / VT490i

Dual humidity and temperature sensor /

Pressure, humidity & temperature sensor





Additional power for long chain

When connecting a very long chain, you need to use CAN-12V-1A / CAN Power Supply module for an additional power for CAN units/extensions/sensors every 8-12 sensors.

see also: