Eagle Eye Power Solutions

HGD-2000 H2 Hydrogen Detector and Sensor

In Stock

The HGD-2000 H2 Hydrogen Detector and Sensor allows the user to monitor hydrogen gas buildup in storage rooms and facilities that house batteries. The HGD-2000 is easy-to-use and easy-to-install. The detector has a terminal block for connection to a single-phase AC power source and two internal relays. The relays can be used to switch a remote exhaust fan and/or alarm on and off. If the concentration of hydrogen gas in the air surrounding the sensor reaches 1% by volume, the yellow LED will light and the 1% internal relay will close. A four-second delay prevents false activation. If the concentration reaches 2%, the red LED will flash, the internal 80db warning alarm will sound, and the 2% internal relay will close.


  • Automatic Operation and Continuous 24/7 Monitoring
  • Long Lifespan for Reliable Monitoring
  • High Sensitivity and Stability
  • Inexpensive protection for equipment and personnel
  • Save insurance costs – reduce insurance premiums when placed in battery charging rooms

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Alarm Relay(2) form C contacts provided, user-configurable connections
Mounting(4) 4.5 mm (3/16 in) screws
Operating EnvironmentTemperature: -10 – 40 °C (14 – 104 °F)
Power Requirements85 – 265 VAC, 50/60 Hz (standard)
17 – 60 VDC (upon request)
ComplianceIEEE Standard 450; National Fire Protection Agency (NFPA)
Article 64; NFPA 2: Hydrogen Technologies Code; Uniform
Building Code (UBC) Section 6400; National Electric Code
(NEC) Section 480.9 (A); NEC 501.125 (B); NEC 501.105 (1)-3
– use in Class 1 Division 2 Group B.
Dimensions178 x 120 x 55 mm (7 x 4.75 x 2.5 in)


What regulations apply to battery charging areas?
OSHA Regulations (Standards – 29 CFR), National Electrical Code (National Fire Protection Association Standard NFPA 70), and associated directives, interpretations and compliance letters apply. For the latest information, see the web sites of OSHA (osha.gov) and NFPA (nfpa.org). Other regulations, state and local, may also apply.

What do these regulations require?
To the best of our knowledge at the time of this posting, existing regulations require that:

  • Provisions be made for sufficient diffusion and ventilation of gases from storage batteries to prevent the accumulation of explosive mixtures.
  • Adequate ventilation means providing natural or mechanical dilution sufficient to limit the accumulation of hydrogen gas in air at the charging site to levels below the lower explosive limit of 4.1%.
  • A typical exhaust fan can meet this requirement if it is used in such manner that the concentration of hydrogen gas in the fan’s ambient air never exceeds the lower explosive limit.
  • What can cause a hydrogen gas explosion?
    Hydrogen gas, 4.1% or more mixed with air, can be ignited by a flame, spark, or static electricity.

Can the detector itself cause an explosion?
Not if you make tight wire connections to the detector. The only moving parts are in the internal relays, and the relays are hermetically sealed.

Will the detector work in a non-oxygen environment?
No. The sensor requires an oxygen environment.

Does the detector detect or react to other gasses?
The sensor detects several other combustible gases in addition to hydrogen — ethanol, isobutane, methane, propane. Its sensitivity to these other gasses, however, is much lower than its sensitivity to hydrogen. This should not noticeably affect its operation.

What is the detector operating temperature?
The detector operating temperature is 14 to 104 degrees F, ( -10 to 40 degrees C).

What is the response time?
When power is first applied, or after a power interruption, approximately 10 minutes will elapse before the detector starts to function. This delay is to prevent false activation. After this delay, response time to hydrogen for the first (1%) relay is about 4 seconds; response time for the second (2%) relay and/or alarm is 3 seconds later (total: about 7 seconds).

Does the detector have a built-in warning alarm?
The detector has a built-in 80 db warning alarm that activates at a 2% concentration of hydrogen.

Where should I place the hydrogen gas detector?
Install the detector at the highest, draft-free location in the battery compartment or room where hydrogen gas might accumulate.

How do I install the detector?
The detector is designed to attach directly to a wall or ceiling, or to a conduit box, using four screws. You will need to run power and relay wires to the detector, plus a modular cable to the optional remote, if used.

How is the detector powered?
Normal power is 115 volts 50/60 Hz AC. If specified at time of order, the detector can be customized for 220 volts 50/60 Hz AC, or for 24, 36 or 48 volts DC.

How much power does the detector consume?
The detector consumes 80 ma, 170 ma if the buzzer is sounding.

How large an exhaust fan can the detector control?
The internal relay dry-contacts are rated at 10 amps / 250 vac, sufficient for most 1/3 HP fans. For higher current requirements, add an external relay.

How many detectors do I need?
Similar to smoke detectors, hydrogen detectors sense hydrogen only at the sensor, not at a distance. How many detectors you need depends upon where hydrogen might accumulate near your ceiling. Factors affecting this are: a. Room size. b. Type of ceiling — flat, pitched, compartmented, etc. c. Natural air flow patterns. If unsure, add one or more detectors to be safe.

Can one detector control more than one sensor?
No. The detector can operate only one sensor.

Can the sensor be remotely mounted from the detector?
Normally, no. The sensor is mounted on a small board inside the detector. For special OEM requirements, some modifications can be made. Consult Eagle Eye.

How can I be sure the detector is working?
Each detector has a test button. Push and hold the test button for ten seconds. The LED’s will light in sequence, the relay(s) will close to operate whatever is connected, and the warning buzzer will sound. This test can also be run from the optional remote, if used. This procedure will test the detector’s electronics, but not the sensor itself. There is no way accurately to test the sensor in the field. If you have hydrogen in a tank, you can fill a balloon with hydrogen and release it at the sensor to see the reaction. Do not use hydrogen sulfide – it can damage the sensor. For a more accurate test, you can purchase test gas from a gas supplier and flood the sensor with it, but these concentrations are very small and may not give a correct result. Fortunately, when the sensor fails, often due to contamination, it normally becomes more sensitive, falsely activating the relay and/or alarm.

How does the detector connect to the optional remote box?
The remote box connects to the detector box via a standard style 6-connector, 6-contact telephone-type modular cable.

How long will the sensor last?
Normal sensor life is over 5 years. For safety sake we suggest you replace it every 5 years.

How can I replace the sensor?
To replace the sensor, order a new sensor board from your dealer or Eagle Eye. Remove the cover of the detector. Pull out the old sensor board and insert the new board. Replace the cover. Run the push-to-test-button procedure. That’s all there is to it.

What is the warranty?
Hydrogen gas detectors are warranted to be free of defects in workmanship and material for a period of 12 months from the date of purchase.

Where can I buy an Eagle Eye HGD-2000?
You can buy a detector directly from Eagle Eye Power Solutions, LLC.

What is the recommended wiring gauge for installing the HGD-2000?
You should consult your electrician or an engineer for the proper wire gauge for your application. You will want a wire gauge that is sufficient for carrying the appropriate load from your circuit breaker which may vary in size based on 120/220 VAC and your specific application.

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