Multi IR Hydrocarbon and Hydrogen Flame Detector User Guide
62
Outputs
Table 23: 20mA Current Output
State
Output
Fault
0+1mA
BIT Fault
2mA±10%
Normal
4mA±10%
Warning
16mA±5%
Alarm
20mA±5%
HART Protocol
The HART protocol is a digital communication signal at
a low level on top of the 0
–
20mA. This bi-directional
field communication protocol is used to communicate
between intelligent field instruments and the host
system. HART is available in wiring options 2 and 3.
Through the HART protocol the detector can:
Display setup
Reconfigure setup
Display detector status and definition
Perform detector diagnostics
Troubleshoot
For more details refer to
HART Manual TM777030
.
Communication Network
: The detector is equipped
with an RS-485 communication link that can be used
in installations with computerized controllers.
The communications protocol is Modbus compatible.
This protocol is a standard and widely used.
It enables continuous communication between a
standard Modbus controller (Master device) and a
serial Network of up to 247 detectors.
Heated
Optics
The front window can be heated to improve performance
in ice, condensation, and snow conditions. The heater
increases the temperature of the optical surface by 5
–
8°F
/ 3
–
5°C above the ambient temperature. The heated
optics can be configured in 3 ways:
Off
: The optics are not heated
On
: The optics are heated continuously
Auto
: Operated only when the change of temperature
requires the heating (default)
In
Auto
mode the start heating temperature can be
defined between 32
–
86°F / 0
–
30°C. The detector stops
heating the window when the temperature is 27°F/15°C
above the start temperature.
