13.3.2 Installing Aggregated Supply Air Temperature Sensors
On systems with large supply air plenums, up to five additional 2T sensors may be connected (via CANbus) in addition to
the standard supply air sensor. iCOM then aggregates the readings and converts to average or maximum values for supply
control.
NOTE: The 2T sensors used for supply air sensor aggregation are identical to the wired-remote sensors and are
added in addition to the up to 10 remote sensors. You may install the supply air sensors at the end of the wired remote
CANbus link or as a separate CANbus loop tied back to the control board and properly terminated.
The sensor array consists of 2T sensors that each have two temperature probes on a 6 ft (1.8 m) probe connection cable and
requires several steps to prepare, connect, and begin monitoring the racks:
• Set DIP switches in each sensor.
• Terminate final sensor on CANbus link.
• Install sensors.
• Install CANbus cabling between sensors.
• Connect CANbus cable to the cooling unit.
• Configure the sensors in iCOM.
Setting DIP Switches and Labeling Supply Air Sensors
Supply sensors A through E have dual purpose CANbus node IDs in iCOM software and may be alternately used for air
temperature/humidity monitoring or fluid temperature monitoring. Table 12.4 on the facing page, indicates the Node IDs
and the alternate use.
Once installed, iCOM recognizes the as supply air sensors, distinguished from the wired remote sensors that may be in use.
Before installing the supply air sensors, make sure that the CANbus node IDs are not already in use. Duplicate sensors will
cause loss of sensor communication.
Tools required:
• Small non-conductive tool to set switches
• Small Phillips head screw driver to open 2T housing.
Each sensor requires a unique address on the CANbus cable connected to the cooling unit. We recommend that you set the
DIP switch sensor-number setting to correspond to the sensor’s location on the CANbus run. If settings are incorrect, the
control will not operate properly.
NOTE: Sensors are connected in a daisy chain to the cooling unit control board. Do not run individual wires from the
sensors to the cooling unit.
1. Apply numbered stickers to the sensor housing that corresponds to the sensor’s position in the chain.
2. Locate the DIP switch hole on the rear of the sensor housing, Figure 12.16 on the facing page.
– or –
If the hole is not present, or the settings are difficult to make through the hole, remove the cover by removing
the Phillips head screws (typically three).
NOTE: Use the non-conductive DIP switch tool (included) or a similar tool to set switches. Do not insert any metal
object into the sensor case.
Vertiv™ | Liebert® iCOM™Installer/User Guide
122
To Next Page
Loading...
Need help?
General