VT490 / Humidity and temperature sensor

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 a maximum of x12 CAN sensors and CAN devices together on one CAN bus (approximately)!

   If you want to connect more than x12 CAN units, you need to use CAN-12V-1A / CAN Power Supply

2. 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:

• VT408 / Extension unit

• VT430 / Rack control unit

• VT440 / Dry contacts unit

• VT450 / Pressure, humidity, temperature...

• VT460 / Smoke, humidity, temperature...

• VT490 / Humidity and temperature sensor

CAN extensions:

• VT408 / Extension unit

• CAN-12V-1A / CAN Power Supply Module

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.

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.

LEDs

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

Additional power for long-chain

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

x2 CAN port systems

Some Vutlan main monitoring systems have x2 CAN ports. That means they can support two individual CAN chains. Each chain has to be configured individually. E.g. “VT855t / Data center monitoring unit” has x2 CAN ports.

Additional reading

see also:

• Comparison chart: Extension units, CAN devices, Sensors
• VT408 / Analog sensor extension unit
• VT408DIN / Extension unit
• VT430 / Rack control unit
• VT440 / Dry contacts unit & VT32 / Dry contacts board extension
• VT450 / Pressure, humidity and temperature sensor
• VT490 / Humidity and temperature sensor
• CAN-12V-1A / CAN Power Supply
• VT460 / Smoke, humidity, temperature sensor (v8.1)

see also:

Setting up CAN

Enable CAN

Inside the web interface of the system go to >> Preferences menu >> Network tab >> Enable CAN >> Save >> Save settings to flash (An icon in the top right corner of the web interface)

Configuration

CAN bus is used for the connection of CAN sensors and CAN modules.

Before using the CAN sensor module, the CAN bus must be configured to operate with this CAN sensor module.

To configure the CAN bus go to "Main menu" >> "CAN configuration" menu.

Each station tab contains current information on the status of the node and a list of  CAN sensor modules connected to this node. 

The following operations can be carried out on the CAN bus node:

• Refresh - updates the current information on the status of the node;

• Configure -  launches configuration process of the nodes for CAN sensor modules connected to it, the old configuration is lost

• Save - saves the list of CAN sensor modules in flash memory;

• Restart - Restart the CAN bus node.

To delete a CAN sensor module, click on the desired module. A modal window will pop up. Press "Delete" and confirm.

To set up a CAN bus node for operation with the CAN sensor module, connect the CAN module to the CAN network and run the corresponding configuration procedure in the web interface using the command "Configure". The configuration process is displayed at the bottom of the tab and lasts approx. 2 minutes.  Detected modules will be added to the list of modules during the configuration process. After completing configuration the node returns to its normal operation. Sensors of detected CAN modules are added to the tree of elements. 

The names of the sensors are automatically set in the form {module name}{serial number}-{type of sensor} and can be edited.

If you need to remove the CAN sensor module from the configuration list use the command Delete, then use the command "Save" to apply the changes you made and restart the node using the command Restart.

Configuring VT408

Additional reading

CAN devices connection