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•
* In wiring options 3, 5 the relay is normally energized
open during normal operation of the detector. The relay is
de-energized close contact if a fault condition or low
voltage situation occurs.
•
0-20mA Current Output
: The 0-20mA can be Sink or Source
according to the wiring option source (see
General Instructions
for Electrical Wiring
on page 40). The maximum permitted
load resistance is 600O.
Table 24: 20 mA Current Output
State
Output
Fault
0 + 0.5 mA
BIT Fault
2 mA±10%
Normal
5 mA±10%
Warning
10 mA±5%
Alarm
15 mA±5%
•
HART Protocol
The HART is a digital communication signal at a low level on top
of the 0-20mA. This is a bi-directional field communication
protocol used to communicate between intelligent field instruments
and the host system.
Through HART protocol the detector can:
•
Display set-up
•
Reconfigure the set-up
•
Display detector status and definition
•
Perform detector diagnostics
•
Troubleshoot
For more details refer to
HART Manual 777030
.
•
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.
Headed Optics
The front window can be heated to improve performance in icing,
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 three 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°F - 122°F (0°C - 50°C). The detector stops heating the window
when the temperature is 27°F (15°C) above the start temperature.
Summary of Contents for SharpEye NP40IGB
Page 1: ...Ref NP40IGB REV A Nov 2009 USER GUIDE...
Page 35: ...36 Appendices...
Page 49: ...50...
Page 50: ...51...