Sensors
This tab allows lab staff to describe sensors that UW CORAL will
track, and optionally define actions to be taken if the sensor value
goes out of range.
Sensor values are summarized and graphed on the Lab > Sensors tab.
Each sensor has the following properties:
- Name
- A human-readable name for the sensor.
- Lab
- The lab that owns the sensor. Notifications will be sent to all users with the maintenance role in the given lab when the sensor alarms.
- Location
- The location that will be shut down (or marked with a problem or comment) when the sensor alarms.
- Poll Frequency
- The frequency at which the sensor is attempted to be polled. Because the sensors are polled in a round-robin fashion, the actual polling frequency is likely to be lower than what is recorded here.
- Sensor URL
- Defines the protocol and address that UW CROAL will use to read the sensor. At the time of this writing, the following protocols are supported: snf:, proxr:, uwep:, uwep4:, fgmp:, and snmp:.
- Formula
- A SQL formula that is used to convert the raw value (written as rawvalue) to the actual value read. For example, ProXR temperature sensors use the formula (rawvalue * 0.3175) - 36.1282. Please note that the formula is sanitized to avoid Bobby Drop Tables.
- Inertia
- How much of the previous value is mixed with the new raw value before conversion, in an attempt to reduce noise. The formula applied is newvalue := (newvalue + oldvalue * inertia) / (1 + inertia) .
- Units
- The units of the converted value.
- Log Scale?
- If this box is checked, graphs will be shown with a log scale on the Y axis.
- Associated Equipment
- The equipment that will be shut down (or marked with a problem or comment) when the sensor alarms, if no Location is given above.
- Flags: Do not alarm
- Do not alarm regardless of the low/high alarm values. Sensors can be temporarily disabled by setting this flag.
- Flags: Interlocked
- Flags: Post shutdown
- Post a shutdown when the alarm triggers. Please note that shutdowns are not closed when the sensor value goes back within bounds.
- Flags: Post problem
- Post a problem when the sensor value goes out of bounds.
- Flags: Post comment
- Post a comment when the sensor value goes out of bounds.
- Interlock URL
- If the sensor alarms, disable (lock) this interlock. Unlike shutdowns/problems/comments, the interlock is re-enabled when the sensor value goes back within bounds.
- Minimum value
- The minimum valid raw sensor value. Raw values lower than this will be silently ignored.
- Maximum value
- The maximum valid raw sensor value. Raw values higher than this will be silently ignored.
- Low alarm
- The sensor will report an alarm if the converted value is lower than this.
- High alarm
- The sensor will report an alarm if the converted value is higher than this.
- Active?
- Sensors that are not Active will not be polled.
Please note that UW CORAL is not a life safety system. The actions
that UW CORAL takes in response to sensor readings should be secondary
to actual life safety response.