+ Post New Thread
Results 1 to 7 of 7
  1. #1
    Advanced Member level 2
    Points: 3,917, Level: 14
    Achievements:
    7 years registered
    imranahmed's Avatar
    Join Date
    Dec 2011
    Location
    Karachi,Pakistan
    Posts
    632
    Helped
    3 / 3
    Points
    3,917
    Level
    14

    HF-24 Ultra-Violet Flame Detector

    Please let me know that I have UV flame detector HF-24.His datasheet shows two voltages ONE is Rated Voltage (24VDC) and SECOND is Working Voltage (15 ~ 30)VDC.

    What is the difference between Rated Voltage and Working Voltage and
    maximum switching current (250mA)?

    I want to know what is the output of UV detector,is there VOLTAGE or CURRENT?

    Please find attached the front and back side of UV Flame Detector.

    Click image for larger version. 

Name:	HF-24_1.jpg 
Views:	0 
Size:	8.1 KB 
ID:	156915
    Click image for larger version. 

Name:	HF-24_2.jpg 
Views:	0 
Size:	250.7 KB 
ID:	156916
    IMRAN

    •   AltAdvertisement

        
       

  2. #2
    Super Moderator
    Points: 263,400, Level: 100
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    46,020
    Helped
    13995 / 13995
    Points
    263,400
    Level
    100

    Re: HF-24 Ultra-Violet Flame Detector

    You want to study the operation principle of Hochiki and similar smoke and fire detection systems. Essentially you have a bus line powered with current limited 24V DC and multiple detectors connected to it in parallel. If one sensor triggers an alarm, it pulls a high current (e.g. 50 to 150 mA) from the line.


    1 members found this post helpful.

    •   AltAdvertisement

        
       

  3. #3
    Advanced Member level 2
    Points: 3,917, Level: 14
    Achievements:
    7 years registered
    imranahmed's Avatar
    Join Date
    Dec 2011
    Location
    Karachi,Pakistan
    Posts
    632
    Helped
    3 / 3
    Points
    3,917
    Level
    14

    Re: HF-24 Ultra-Violet Flame Detector

    Means if one sensor detects flame then all parallel connected detectors will energized and also triggers signal for alarm?

    Can we obtain alarm signal from its (HF-24) output terminals by connecting shunt resistor of 2k or 3.9k?

    - - - Updated - - -

    Quote Originally Posted by imranahmed View Post
    Means if one sensor detects flame then all parallel connected detectors will energized and also triggers signal for alarm?

    Can we obtain alarm signal from its (HF-24) output terminals by connecting shunt resistor of 2k or 3.9k?
    OUTPUT SIGNAL as a VOLTAGE?
    Last edited by imranahmed; 15th December 2019 at 11:59.
    IMRAN



    •   AltAdvertisement

        
       

  4. #4
    Super Moderator
    Points: 263,400, Level: 100
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    46,020
    Helped
    13995 / 13995
    Points
    263,400
    Level
    100

    Re: HF-24 Ultra-Violet Flame Detector

    Not sure what you consider as shunt resistor? The detector is a two terminal device, it has no separate output terminals.


    1 members found this post helpful.

  5. #5
    Advanced Member level 2
    Points: 3,917, Level: 14
    Achievements:
    7 years registered
    imranahmed's Avatar
    Join Date
    Dec 2011
    Location
    Karachi,Pakistan
    Posts
    632
    Helped
    3 / 3
    Points
    3,917
    Level
    14

    Re: HF-24 Ultra-Violet Flame Detector

    My question was that what will be the output of flame detector Current or Voltage?

    And at long distance how the signal will be transmit as datasheet says Maximum Alarm Switching Current is 250mA.
    IMRAN



    •   AltAdvertisement

        
       

  6. #6
    Super Moderator
    Points: 82,583, Level: 70
    Achievements:
    7 years registered
    Awards:
    2nd Helpful Member
    betwixt's Avatar
    Join Date
    Jul 2009
    Location
    Aberdyfi, West Wales, UK
    Posts
    13,557
    Helped
    4515 / 4515
    Points
    82,583
    Level
    70

    Re: HF-24 Ultra-Violet Flame Detector

    You will have to ask the manufacturer.

    Most devices like this use three wires, two are the supply, the third 'switched' wire is linked to all the other detectors in parallel. The idea is that if one detector senses a flame it operates the alarm on all of them so it is heard over a greater distance. However, the specification in the link does not mention it has a built-in alarm at all so it may use a custom interface designed by Hochiki. It only states it is compatible with their other bases.

    Brian.
    PLEASE - no friends requests or private emails, I simply don't have time to reply to them all.
    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.


    1 members found this post helpful.

  7. #7
    Super Moderator
    Points: 263,400, Level: 100
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    46,020
    Helped
    13995 / 13995
    Points
    263,400
    Level
    100

    Re: HF-24 Ultra-Violet Flame Detector

    Why not review the Hochiki product manuals and installation instructions?


    1 members found this post helpful.

--[[ ]]--