Senquip ORB-X1-G, User Manual

Page: 75 / 136

Hot junction accuracy +-0.25°C (typical)
Hot junction accuracy +-0.5°C (0 to 85°C)
Cold junction ac-0.5°C (typical)
Cold junction ac-1.0°C (0 to 85°C)
Thermocouple Type Temperature range
Type K: -200 to +1372°C
Type J: -150 to +1200°C
Type T: -200 to +400°C
Type N: -150 to +1300°C
Type E: -200 to +1000°C
Type S: 250 to +1664°C
Type B: 1000 to +1800°C
Type R: 250 to +1664°C
Thermocouple correction coefficients are derived from the National Institute of Standards and Technology
(NIST) ITS-90 Thermocouple Database.
6.4.2 Settings
The ORB can be configured to use K, J, T, N, S, E, B and R-Type Thermocouples using the type setting. It is
important to select the correct thermocouple type in order to maximise temperature measurement accu-
racy.
Measurements can be scheduled as a multiple of the base-interval. The fastest possible measurement rate
is achieved by setting the interval to 1 in which case measurements will occur on every base interval.
After each measurement, the ORB can be configured to compare the value to preset warning and alarm
levels. To reduce power consumption, the measurement rate can be turned down by increasing the
interval.
Warning and alarm thresholds can be enabled. Once enabled, each time a measurement is completed, the
returned value will be compared with minimum and maximum warning and alarm thresholds. If a
warning or alarm level is breached, a message will immediately be transmitted. Hysteresis can be specified
in 1°C increments, to prevent multiple alarms in the presence of noisy signals.
A full list of temperature sensor settings is given in the table at the end of this chapter.
6.5 CAN Bus Interface
The ORB-C1 has a CAN bus interface that can be used to read data from all kinds of vehicles and sensors
that use CAN as their communications medium. Hundreds of sensors can be connected to a single CAN
network.
In many cases, the protocol that is being used on the CAN bus is known, and so large volumes of under-
standable data can be extracted from all kinds of vehicles. Common CAN protocols include:
• J1939, the dominating CAN-based protocol for trucks and busses.
• ISO 11783, a J1939 flavor for agricultural tractors.
• ISO 11992, an interface between trucks and trailers.
• NMEA 2000, a protocol based on J1939 for marine use.
• CANopen, provides a standard for industrial machinery commonly used in industrial automation.
ORB User Guide, Release 1.1
6.5. CAN Bus Interface 69