Yes. You can connect the sensors to the CAN bus port of the Didactum alarm strips/monitoring systems while the system is running. Please note that the Monitoring System 50 does not have a CAN bus port.

The smoke detector integrated into the combined CAN multisensor can be reset using the SNMP SET command. To do this, replace the OID .1.3.6.1.4.1.39052.6.1.1.11 (ctlCANSensorsDiscretSpecific) with the sensor ID in the string value "reset smoke" (without quotation marks).

Our engineers recommend using cables such as UTP Cat3.5.6 with a 24AWG copper core. It is also possible to use a 4-core or 6-core TRONIC or UTP-CCA cable. Please note that this may reduce the maximum length of the CAN bus line.

The maximum length of the CAN bus for Didactum measurement and monitoring systems is 250 meters. This is because the ohmic resistance of patch cables equipped with RJ12 connectors is limited.

It is possible to connect up to 8 CAN sensors/units to the CAN bus port of the monitoring system. Important note: The Entry Monitoring System 50 is not equipped with a CAN bus connection. Only Didactum's analog SNMP sensors can be connected here!

No. Monitoring hardware with a CAN bus connection is always required. This SNMP-compatible hardware handles monitoring, data logging, surveillance, and power supply for the connected sensors. As of August 2020, the Didactum monitoring systems of the 100 (DC) / 200 / 300 (PoE) / 400 / 500 (DC) / 600 (DC) and 700 (DC) series support the combined CAN bus temperature and humidity sensor.

Please check the cable connections between the individual CAN devices and CAN sensors. Also check that the individual connectors are properly seated. For testing purposes, be sure to use the original Didactum CAN cables included in the delivery. Often, it has been found that the RJ12 patch cable crimped by the customer is faulty or too short. Furthermore, please check all CAN devices and/or CAN multi-sensors in the CAN bus for any termination errors. Often, the termination (TR switch) on an intermediate CAN device is accidentally switched on (so-called TR ON position). Only the last CAN device in the CAN bus should be terminated! Please also check if the "CR switch" on any of the CAN devices is set to "ON". This switch must be set to "OFF" on all CAN units.

Please check if the CAN bus is enabled in the web interface of the IT monitoring system. To do this, simply go to the menu item “System settings” => “Network” => “Enable CAN” and then check the box. Afterwards, please click on the floppy disk icon in the upper right corner to permanently save the settings in the IT monitoring system.

Each Didactum® CAN sensor and each Didactum® CAN unit comes with a 2-meter-long, shielded connection cable with shielded connectors. Should you require longer cables for CAN sensors and CAN units, please use a shielded, brand-name cable. Ideally, this 6-core cable should be suitable for low and high temperature ranges and resistant to oil and most chemical compounds. Please ensure that the corresponding RJ12 connectors of your CAN bus cable are also shielded.

The Didactum® sensor group is divided into CAN bus (Control Area Network) sensors and analog sensors. The 500/500-DC/600 rack monitoring systems support both CAN bus and analog Didactum® sensors. Didactum® CAN bus sensors can be wired serially and connected in series. This saves time and money on sensor wiring. The two CAN bus ports on the Didactum® alarm servers support a maximum total length of 300 meters each. Ideal for environmental monitoring of large (IT) infrastructures.

Two sensors from the Didactum® analog sensor group can also be cascaded/connected in series. This applies (as of June 2014) to Didactum® smoke detectors and Didactum® vibration detectors. For example, 10 smoke detector sensors can be daisy-chained using only one analog sensor port. Please note that your Didactum® room monitoring system will only recognize multiple analog sensors as a single unit when connected in series.

Alternatively, you can connect each analog sensor individually to the eight analog sensor ports on the main unit or the sensor expansion unit. Each sensor will then be displayed individually in the web interface and can be configured accordingly. Further information can be found in the datasheets for the respective Didactum® sensors.

Didactum smoke detectors are cascadeable. You can connect up to 30 of these smoke detectors in series using inexpensive RJ12 patch cables. This only occupies one analog sensor port on your Didactum IP monitoring system. The total length of the sensor chain can be up to 150 meters.

All Didactum rack monitoring systems, as well as Didactum CAN sensors and CAN expansion units, feature terminators in the form of jumpers. Always terminate the ends of each CAN line to minimize potential reflections and interference on the CAN bus. Shorter CAN connections should be terminated at least on one end. Terminating the CAN bus line is accomplished in just a few seconds by simply setting jumpers.

You will find an answer regarding CAN Bus (Controller Area Network) in the form of the comparison table below

All Didactum IP-based measurement and monitoring systems offer extensive group functionality. The intelligent IP sensors or the digital/potential-free contacts can be grouped individually. In the "System Tree" section, click the "+" icon. This will open a window labeled "Add a new element."

Select "Group" from the list. Give the new group a name (e.g., "Fault Alarm Collective Contacts") and then select the relevant potential-free contacts under "Elements." Save your settings. The newly created "Fault Alarm Collective Contacts" group will now appear in the "System Tree." In the "Logical Scheme" menu, you can define the desired notification and alarm types for the new "Fault Alarm Collective Contacts" group, such as email alerts, SMS alerts, relay switching, or sending SNMP traps to OPC servers or building management software.

Please note that only digital CAN multi-sensors and CAN expansion units (Didactum sensor boxes, etc.) can be connected to the CAN bus port. Analog sensors can only be connected to the analog sensor ports (labeled P1, P2, P3, P4). If you are using the expansion box for intelligent analog sensors, please connect your temperature sensor there.

Didactum's Ethernet-based monitoring systems exclusively support Didactum brand CAN sensors and devices. Third-party CAN sensors and devices are not supported. However, it is possible to integrate third-party analog sensors into Didactum's Ethernet-based measurement and monitoring devices using the DC current sensor or the 4-20 mA converter.

Didactum's digital CAN multi-sensors and CAN units have LEDs that can indicate the following states (as of September 2019):

• Solid red light, flashing green light: No communication with the Didactum main unit. Please check the RJ12 wiring. Test the connection with the original shielded cable.
• Solid red light, green LED off: A connection to the Didactum main unit exists, but the digital CAN sensor or CAN unit has not yet been configured in the web GUI.
• Solid red light off, green LED on: The CAN sensors and CAN units are working correctly with the Didactum monitoring device.
• LEDs off: The CAN sensor or CAN unit is not receiving power. Check the power supply to the IT monitoring device and the RJ12 wiring. Please use the original Didactum CAN bus cable. Please also check the correct termination of the sensor or CAN unit. A technical defect may also be present.