**NEW**: Hydrogen Sensor

12 April 2021

Hydrogen – the underestimated danger

Lead-based batteries as well as any other type of “wetcells” like NiCDs are charged by a chemical process. As a side effect of this chemical process, the battery emits hydrogen, which is either subsequently recombined or lost into the surrounding atmosphere. Depending on the design of the battery, this hydrogen escapes from vent valves or is released directly into the environment. With AGM batteries such a case is negligible, but it occurs to a significant extent with "wet cells".
Hydrogen is odorless, colorless and lighter than air - in smaller concentrations it is nothing unusual in nature and does not constitute any risk.

It is a different matter in battery rooms:

  • In ceiling areas or in dropped ceilings
  • Storage areas such as shelves
  • Static air vortices in the ceiling area due to ventilation

As soon as a general air saturation of at least 4.1% hydrogen to 75% air is reached, a highly explosive gas mixture is formed.  Even small sparks from switches or electrical discharges can be enough to cause ignition, which could lead to disastrous results.

Since hydrogen saturation in the air is colorless and odorless, special sensors are needed to detect the formation of such a gas mixture thus allowing for adequate reactive measures. A battery monitoring system displays the battery parameters but would not detect liquid losses due to gas formation. Therefore, larger UPS solutions that are placed inside poorly ventilated areas should use a hydrogen sensor as an additional safeguard. The new H2 sensor “SMH2LC” from GENEREX is operated standalone; alarms are triggered via the alarm contacts and optically and acoustically (optional), but can also be connected to CS141/BACS via the GXRAUX.

New for the European market

With the SMH2LC, GENEREX has introduced an incomparably favorable high-performance hydrogen sensor to the European market!

The highlights of the SMH2LC include:

  • Easy installation and centralized configuration
    The sensor heads are pre-configured and calibrated –No additional configuration work on the sensor station is required.
  • Power supply from the base station
    As the central control unit, the BACS Webmanager in combination with a GXRAUX module also manages the power supply to the sensor. Up to 15-meter-long cables can lie between the Webmanager and the sensor for structured cabling.
  • Daisy chains and visual warning behavior
    Up to 5 sensors can be coupled in a daisy chain. When the Webmanager indicates an error, the cause of the warning or alarm can be identified through a simple on-site visual check.
  • Flexible
    In addition to hydrogen, the standard sensor also responds to other gas accumulations such as nitrogen. The internal sensor technology can be easily exchanged as needed and thereby adapted to the respective operating environment with its particular gas mixtures.
  • Calibration
    In general, all gas sensors on the market must be calibrated at regular intervals. A special feature of the SMH2LC is that this calibration can be carried out particularly easily. The sensor head is replaced by a spare part: Open the housing, loosen the screw from the sensor head and replace the sensor module as a whole. The replacement can be carried out as part of regular maintenance work! The uncomplicated replacement of the sensor by the user also makes calibration much more cost-effective than with other H2 sensors on the market.

The new SMH2LC is now available!
*) The sensor is not UL-certified and is therefore not permitted to be used on the American marke