Xuzhou Nendar Combustion Control Engineering Co., Ltd
http://www.nendar.com
Phone：0516-83899666
postcode：221008
E-mail：xznengda@126.com
Address：Hardware district 1 11，National University Science Park of China University of Mining and Technology，Xuzhou,Jiangsu,China

NDHJ-9 Intelligent Flame Detector With Remote Communication

1.Description

NDHJ-9 flame detector with remote communication of liquid crystal display (LCD) is mainly used for flame monitoring of various kinds of fuel oil and coal with very strong flexibility. It adopts the latest digital processing technology and pattern recognition software and hardware, which can accurately distinguish between flame sensor produced by the pulse rate and have the best ability of identification. It adopts LCD display target flame intensity, frequency, flame on, fault and information such as mode setting. It uses RS485 and RS232 interface with PC for remote communication and only display status information of flame detector which can also be set up on the options. NDHJ-9 Intelligent flame detector with remote communication not only has the function of test, but also has breakdown self-check function, therefore it has higher security.

2.Technical parameters

Sensitivity		≥100Lx（λ₀=550nm）
Response time	Flame On	≤1.5s
	Flame Off	2.5-5s
Detection object		coal and fuel oil flame
Output of flame on		A set of normally open contacts 220VAC50Hz 1A；24VDC 1A
Output of fault		A set of normally open contacts 220VAC50Hz 1A；24VDC 1A
Analog output of flame intensity		4-20mA DC，maximum load 1KΩ
Delay time of flame off		1-6s It can be adjusted by the user
Manner of working		Long-term continuous
Environment temperature	Fiber lens group	forepart≤450℃，posterior≤85℃
	Processor	0-85℃
Environmental humidity		≤180%RH
Probe cooling way		Air cooling：flux≥25.5m3/min Differential pressure between entrance and furnace≥150mmH2O
Power supply		220VAC
power dissipation		80W
The length of the probe		400-6000mm
Communication interface		RS485 RS232

3.Main structure and working principle

3.1 Main structure

NDHJ - 9 type flame detector is composed of fiber, lens, photoelectric conversion, pretreatment circuit, processor and power section.

Optical fiber is made by drawing of high refractive index of core body and low refractive index of cladding materials. Core body has good performance of transmission of light, which will transfer flame signals from the front-end to the back-end lens group at very low attenuation. The goal of flame light after being in focus group through the optical lens which is located in the forefront of probe will be passed to the optical fiber end face, then it will be send to the photoelectric conversion and preprocessing circuit on the photoelectric converter through the optical fiber transmission. Photoelectric converter is opposite the optical fiber end face. The fire signal which is received by the photoelectric converter is converted to electrical signals. Then the electrical signals are sent to processor that digital processing of flame intensity and pulse frequency.

3.2 Working principle

Processor CPU in the acquisition by the photoelectric signal converter, and then through a series of processing, calculation, and then the intensity of the flame, pulse frequency, fire signal, the fault signal in the LCD display, respectively and according to the pre-set fire and no fire recognition standard automatic recognition, given the corresponding signals and instructions, set up the state display options and Settings.

Fault diagnosis is based on judgment of the CPU processor for the signal passing a photoelectric converter. It will be judged fault status when the CPU found abnormal signal, at the same time fault signals and instructions are presented also.

Flame on and fault signals through a set of their own passive relay contact output.

In addition, the processor also provides the 4-20mADC analog signal output for analog display for external fire intensity.

NDHJ - 9 type flame detector consists of eight completely independent intelligent amplifier and two of 12VDC power supply modules. Two power supplies are redundant which can output a steady 12VDC power supply flame detector analog circuits. Flame detector with 5VDC voltage regulator circuit output provides power for digital circuits. Eight intelligent amplifiers and two power supply modules in one case forming a unity flame detector can be hot plug. It is convenient for replacement and maintenance.

NDHJ - 9 type flame detector is connected to the computer by RS485 and RS232 interface, using the latest flame detector PC software. It can real-time display up to 128 lines flame strength of the flame detector, flame frequency, flame on state, fault state, analog output value. It can also show the flame graph of 4 lines flame detector. The computer can be set flame detector strength threshold, fire frequency threshold, no flame latency time (1-6 seconds),4-20mA simulation output for 128 lines flame detector.