Frequently Asked Questions

General FAQs

How long has H2scan been in business?

H2scan was founded in 2002 with technology licensed From Sandia National Labs.

Where are you located?

H2scan’s factory is located in Valencia, CA, where all of our products are manufactured.

Do the terms “no calibration” and “auto-calibration” mean the same thing?

No, they do not. No calibration implies that the unit has a limited life, cannot be field-calibrated and should be disposed of after its intended service life. The new and improved Hydrogen-Specific Resistive Sensor technology from H2scan auto-calibrate using a patented technology that keeps the unit properly calibrated without the expense of additional services. Additionally, H2scan’s Gen5-series technology can be field-calibrated if desired by the user, although not required.

How does your monitor work?

H2scan sensors utilize proprietary Hydrogen-Specific Resistive Sensor technology that measures the sensor’s response when in contact with Hydrogen. This response is directly proportional to the amount of Hydrogen at the sensor tip and is read as ppm H2. The sensor coating is not consumed or used up in this process and response time can range from several seconds to several minutes, depending on the specific sensor type. The sensors require no maintenance and use no consumables or membranes.

Will the Hydrogen sensor give a false indication because of the presence of other gases?

The sensor is selective for Hydrogen alone. However, it can be affected by high concentrations of certain gases, such as CO, H2S and oxygen.

Is the sensor’s operation affected by pressure?

H2scan sensors are partial-pressure devices and are calibrated at 1 ATM. If the operational pressure at the sensor is higher or lower than 1 ATM, the sensor’s response will be affected in a proportional manner. A pressure-compensating device is recommended for operating pressures other than 1 ATM.

Does the sensor come with software? If not, what is required?

Software is not included with the sensor. The user can talk to the sensor with a variety of applications, depending on the sensor model and desired communication interface –

• GRIDSCAN® or other Gen5 sensor: any Modbus or DNP3 (if enabled) application
• Process Sensors: (RS-232/422): any terminal program, (Modbus): any Modbus application
• OEM Sensors: (RS-232/422): any terminal program, (Modbus): any Modbus application
• Battery Safety Sensors (Gen5-based): any Modbus applications
• H2scan sensors can also communicate via an analog signal, if equipped.

How long has H2scan been in business?

H2scan has been in business for over 20 years servicing the process & safety, transformer and now energy storage & stationary battery market

What approvals/certifications do your sensors have?

• CE Mark for all products
• UL for Safety products
• ATEX, IECEX, TIIS, Kosha, cLC, UL/Explosion Proof and IS for process products

Is a power supply provided?

No, power supplies are not included as standard, but H2scan does offer optional power supplies.

Can the sensor work with or without oxygen present?

The sensor can operate with and without oxygen present but is calibrated per the respective background.

How often does the sensor need calibration?

For the 600, 700, 1600, 1700 and 2700-series products, a verification is recommended every 90 days and, if required, a factory calibration. The Gen5 products do not require calibration by the user, as they perform auto-calibration sequences.

Transformer Products FAQs

General

Are DGA monitors needed? For what transformers (type and size)?

DGA sensors, whether single-gas or multi-gas, are a proven method for early detection of gassing events in transformers. The sensors can be installed on any oil-filled transformer, including distribution, transmission and generation-type transformers. For more information, read the blog, I got 99 Problems, but the Online DGA Monitor Ain’t One.

Why hydrogen monitoring instead of multi-gas?

Hydrogen is generated in a transformer at the same time as all other key gases monitored by a multi-gas DGA system. Hydrogen monitoring can also be added to your protection system for a fraction of the cost of a multi-gas monitor. For more information, read the blog, When Does it Make Sense to Pay Big Bucks for a Multi-Gas DGA Monitor?

Where can / should a DGA sensor be mounted?

The sensor can be mounted to detect H2 in either the gas (head) space or in the dielectric liquid (oil).

Does installing a DGA sensor eliminate the need for manual sampling?

A DGA sensor should not eliminate manual sampling, but it will reduce the number of manual samples required, since there will be a constant stream of real-time data provided. The manual sample can be used as a confirmation of an event detected by the DGA sensor. For more information, read, The Value of Measuring Hydrogen: Why Early Detection Matters for Transformer Health.

Can your sensors be installed on an energized transformer?

Yes, they can, if the installation location is accessible during energized operation and does not conflict with any utility-specific safety restrictions.

Why is Hydrogen used for single gas detection over other IEEE fault gases?

Hydrogen is the first gas to develop in any fault condition and is still being generated as the other gases are also being formed. It is an early-warning indicator of potential harmful conditions. For more information on DGA, read the blog, Answers to Your Transformer Dissolved Gas Analysis Questions and Fault Identification Methods.

What is DGA and how long has it been used?

DGA (Dissolved Gas Analysis) has been consistently used to analyze and predict transformer conditions for several decades, with the earliest uses of analyzing gases dissolved in transformer oil being discussed and studied as early as the 1920s.

What do I do with the information?

The information collected from a DGA, whether from a manual sample or an online monitor, can be input into one of many diagnostic tools or applied against long-standing IEEE guidelines to help the transformer operator gain an understanding of gas trends that may be developing in their transformer and to also help them make informed decisions regarding the operation of this equipment.

What size transformers do your devices apply to?

H2scan’s GRIDSCAN sensors can be installed on any transformer. Their compact footprint and cost-effective pricing make them ideal for monitoring entire transformer fleets – from small distribution pad-mounted transformers to larger transmission and generation transformers.

Does the GRIDSCAN measure anything other than hydrogen?

The GRIDSCAN 5000 also measures oil temperature. The 6000 also measures oil temperature, moisture and pressure.

What is the warranty for the GRIDSCAN?

The GRIDSCAN comes with a standard 3-year warranty from date of shipment from the factory. It can be offered with a 10-year warranty for an additional cost for the sensor.

What is the lifespan of the GRIDSCAN?

The expected lifetime is ~15yrs.

What maintenance is required for the GRIDSCAN?

The GRIDSCAN is a maintenance-free device and does not require any consumables for operation.

How often does the GRIDSCAN need to be calibrated?

The GRIDSCAN is an auto-calibrating device, requiring no input from the user. It performs its auto-calibration every 12 hours. However, the user can perform a field calibration, if desired.

What transformer fluid types is your sensor compatible with?

The GRIDSCAN is compatible with mineral oils, natural esters (FR3), synthetic esters and silicone oils.

What other things can a GRIDSCAN be installed on, besides a transformer?

The GRIDSCAN can be installed on other oil-filled structures in which Hydrogen may develop, such as bushings (oil-filled).

Can I adjust my own alarm levels and how many do I have?

The GRIDSCAN itself does not contain alarm relays or store any settings for alarm limits, but can be connected to the AO-2 Control Hub for this purpose.

Can I incorporate transformer load data with the GRIDSCAN?

The AO-2 Control Hub can combine the GRIDSCAN’s data with an external sensor for transformer load current.

What is Condition-Based Maintenance and why is it better than Time-Based Maintenance?

Condition-Based Maintenance involves a maintenance schedule based on the current condition of the transformer or other asset, as opposed to a schedule that is carried out on a specific time interval, regardless of the condition of the asset. A time-based schedule may involve wasteful maintenance that is either unnecessary at the time or too late to be of any good. Condition-based maintenance does require accurate monitoring to ensure the maintenance is performed when actually needed. For more information read the blog, Causes of Power Transformer Failures in Industrial Applications.

What is meant by an “oil temperature-corrected H2 reading”?

The amount of any particular dissolved gas (not only hydrogen) available to measure in the oil depends on the solubility of that gas in the oil, which is highly temperature dependent. So, we need to know the temperature of the oil, in addition to applying the proper solubility coefficient for the gas involved, to get the proper calculation.

Why isn’t a pump used to circulate oil for a more accurate reading?

Unless moisture is also measured with H2, a pump isn’t necessary, as the H2 will diffuse equally in the oil. In hard-to-reach areas, the response time of the sensor will be affected most. If moisture is also being measured, oil flow becomes a greater concern to get accurate measurements.

Some devices have a probe that inserts into the tank; why doesn’t yours?

As long as the sensor tip is in contact with the appropriate medium (oil or gas headspace), the H2 will contact it.

What method / technology is used to measure moisture on the GRIDSCAN 6000?

It is a capacitive moisture sensor that directly measures the water activity.

What type of pressure sensor is used in the GRIDSCAN 6000?

It is a piezoresistive sensor.

Does the GRIDSCAN 5000/6000 come with any onboard relays?

The GRIDSCAN sensor itself does not include any relays for alarming. The AO-2 Control Hub is an accessory to the GRIDSCAN that includes relays and analog inputs / outputs.

Transformer Installation

Where is the best place to install the sensor on the transformer?

There are several location options, depending on whether the sensor is oil-calibrated or gas-calibrated. The best location for the oil-calibrated sensor would be on a valve on the main tank where the oil flow is known to be good. Installation on a radiator loop is ok, as long as consideration for the oil flow direction and flow rate is taken into account. The gas-calibrated sensor should be installed in the headspace.

What size valve is required to install the sensor?

• 5000: The sensor can be installed on different valve sizes, but an adapter bushing will likely be needed, as the sensor thread size is ¾” NPT and most transformer valves are 1” or 2” NPT. You should always be adapting to an equal (3/4”) size or larger valve size and not down to a lower size than the sensor.
• 6000: A 1.5” NPT threaded KF-40 valve adapter is provided with the 6000. The 6000 is clamped to this adapter with the included KF flange clamp.

What is the power requirement for installation?

24VDC is recommended, but a range of 12VDC to 48 VDC (@10W) will work. NO AC input.

What type of cabling is needed?

• 5000: M12 female (4-pin, shielded) cable, preferably with a twisted pair for the communications.
• 6000: M12 female (5-pin, shielded) cable, w/ 2 18AWG wires for power and 3 22AWG wires for data and communications ground)

Is an air-bleed device required for the installation?

Yes, for the oil-calibrated 5000 sensor only. The 6000 includes an air-bleeding assembly.

Does it matter what position the sensor is mounted?

Yes. It should be mounted as close to horizontal as possible to minimize any trapped air bubbles at the sensor tip. The sensor body angle should be even with or below the horizontal plane.

Can the cables be installed in conduit?

Yes. H2scan offers a conduit adapter that will accommodate ½” conduit.

How is the sensor sealed in the valve?

• 5000: The sensor threads can be sealed with Teflon® tape or any of several other types of pipe-thread sealant readily available.
• 6000: The flange on the valve adapter seals with an O-ring gasket to the flange on the 6000 body. The clamp holds the 6000 to the valve adapter.

Is there a maximum length for the installation to extend from the transformer?

H2scan studies have shown that a length of < 9” from the transformer wall will provide the best sensor performance. Hydrogen will eventually reach the sensor with most any length, but the response time will be slower with greater lengths from the transformer.

Does the GRIDSCAN require an enclosure?

No, it is IP68-rated.

Can the GRIDSCAN be installed on a tap changer?

• 5000: Yes, but only on a vacuum-style tap changer.
• 6000: No

Can I still use my drain valve after the unit is installed?

Yes, if the drain valve is fitted with a tee at the end, which would allow the installation of the GRIDSCAN series in addition to an additional port for servicing the transformer. If there is no tee installed and the GRIDSCAN is installed at the end of the drain valve, the GRIDSCAN would need to be removed prior to servicing the transformer.

What is the maximum length cable that can be used with the GRIDSCAN?

H2scan offers 5, 10, 15 and 30M cable lengths for the GRIDSCAN. The maximum length possible will be determined by the power source available, as well as the data transmission speed. Longer cable lengths will require greater power sources (with larger conductors) and lower baud rates to avoid data drop-out.

Does H2scan offer installation?

While the GRIDSCAN was designed to be self-installed by most users, H2scan is currently exploring the possibility of offering installation services.

How many GRIDSCANs can I connect to an AO-2?

Currently, only one GRIDSCAN can be connected to an AO-2 unit.

How many GRIDSCANs can I connect to a Sentinel?

Currently, only one GRIDSCAN can be connected to a Sentinel.

Is it better to install in oil or gas?

Neither is necessarily better. It depends on the availability and location of valves on the transformer. However, a gas-calibrated GRIDSCAN will have a quicker response time than an oil-calibrated one, as it takes time for H2 to diffuse equally in the transformer oil.

Battery Safety Solutions FAQs

General

Are hydrogen detectors required in battery rooms?

IFC 1207.6.1.2.4 states when required by Section 1207.6.1.2 rooms, areas and walk-in units containing ESS shall be protected by an approved continuous gas detection system that complies with section 916. For more information, read the blog, Managing Hydrogen Risk in Stationary Battery Systems.

What do codes say about hydrogen management?

A Hazardous Mitigation Plan should be created to determine the need for ventilation and detection of hydrogen. State codes reference hydrogen detection systems that activate a fan when hydrogen is detected as an acceptable way to mitigate hydrogen risk.

What battery types produce hydrogen?

All vented lead-acid batteries (VLA), valve-regulated lead-acid (VRLA) batteries and vented nickel cadmium batteries (ni-cad) produce hydrogen while charging, equalizing, float charge and in any kind of abnormal charge condition. For more information, read the blog, Ensuring Battery Room Safety in Europe Navigating Standards and Best Practices.

Are there different hydrogen sensors technologies for battery rooms?

Yes. The two main types of hydrogen-specific sensors are catalytic bead sensors and solid-state sensors. However, there are a few types of solid-state sensors that include one-time use sensors and long-lasting, auto-calibrating technology sensors. One-time use sensors are meant to be used for a short amount of time and then disposed of and replaced. Long-lasting auto-calibrating technology sensors last the entire service life of the battery and beyond. They perform an automated calibration process that ensures their accuracy. H2scan 5000-series sensors are made from precious metals and cannot be consumed or poisoned by other gases.

Is calibration required for all sensors?

Traditional catalytic bead sensors require calibration every 3 to 6 months. The new and improved Hydrogen-Specific Resistive Sensor technology from H2scan (series 5000) performs an automatic calibration, eliminating the need for manual calibration procedures.

Do the terms “no calibration” and “auto-calibration” mean the same thing?

No, they do not. No calibration implies that the unit has a limited life, cannot be field-calibrated and should be disposed of after its intended service life. The new and improved Hydrogen-Specific Resistive Sensor technology from H2scan for battery room applications auto-calibrate using a patented technology that keeps the unit properly calibrated without the expense of additional services. Additionally, H2scan’s 5000-series technology can be field-calibrated if desired by the user, although not required.

How many sensors do I need?

Placement of sensors depends on the room configuration. However, we recommend placing a sensor to cover a 25’ radius or 50’ diameter and cover high parts of a ceiling where gas may be trapped. Bulkhead mounts are also available for enclosed cabinet applications.

How long do sensors last?

H2scan 5000-series sensors will last 10+ years in outdoor applications. Sensors for indoor applications with controlled environments will last longer. In legacy sensor technology, sensors last 3-5 years and the sensor is a wearable item. With the new generation of H2scan sensors, the sensor is made from precious metals and is now the longest lasting component.

What are the communications options?

Sensors communicate via Modbus protocol. This enables the user to connect directly to a Building Management System (BMS), SCADA, DCIM, NOC, fire panels, battery monitors, industrial chargers, UPS, and high-powered relays for fan operation easily without an additional interface.

Is a controller required?

No. You may use a HYVIEW® display from H2scan to provide on-site visual readings from your sensors, but units are enabled with Modbus protocol to communicate with other devices and building systems.

Can sensors be daisy-chained?

Yes. T-adapters are used for daisy-chain configuration which eliminates the need for home-runs to each sensor. The power supply should be properly sized for the application.

Is there a display available?

Yes. The H2scan display is called the HYVIEW and can accept up to 4 sensors per display.

Can I connect my sensors to my battery monitor?

Yes. Most battery monitoring systems accept Modbus communication and can be connected to the sensors for alarming purposes.

What mounting options are available for the sensors?

Currently, there are two mounts available. The general-purpose mount can be used in any application for area monitoring including ceilings and inside cabinets. The bulkhead mounts are designed for cabinet use where space inside the cabinet is limited, or the user wants to access the sensor without reaching into a high-voltage cabinet.

What are the power requirements for the sensors?

Sensors need an input voltage between 9-48 VDC and require 10W of power.

Can sensors be placed in outdoor applications?

Yes. Sensors are designed to be placed outdoors. In the transformer market, our sensors are installed in outdoor transformer applications. H2scan sensors are perfect for outdoor NEMA enclosures.

Process and Safety Products FAQs

General

Can H2scan sensors detect gases other than hydrogen in a process stream?

No, not at this time, but this capability is being explored.

How do I determine the proper sensor for my process?

Customers interested in determining the proper hydrogen sensor for their process should submit a completed CAI (Customer Application Information) form to their Sales Representative and it will be reviewed to determine the proper hydrogen sensor for their application, an RMA form.

Does H2scan make IS-rated sensors?

Yes, H2scan provides both IS and non IS-rated process and safety sensors. Email [email protected] for more information.

What is the maximum flow rate the sensor can operate with?

The recommended process gas flow rate range is 0.1 to 10 SLPM.

What approvals / certifications do your sensors have?

• CE Mark for all products
• UL for Safety products
• ATEX, IECEX, TIIS, Kosha, cLC, UL/Explosion Proof and IS for Process products

What are the output options of the instruments?

The output is given in different ways, depending on the specific model:

• Analog Output (0-5V or 4-20mA)
• RS232 or RS485 serial output
• Built-in Form C relays
• Digital Modbus RS485

How are the different models calibrated?

The calibration process involves applying the necessary gases to the sensor and following the prompts in the sensor’s firmware. This is done via the serial port for all models, except the 2600 and 2700 models, which can be calibrated via a remote control. Directions for the calibration process can be found in the user manual for each product.

Communications

What communications protocol is standard with the GRIDSCAN, HY-ALERTA and HY-OPTIMA series?

Modbus protocol is standard, but DNP3 can be ordered for GRIDSCAN. The HY-ALERTA and HY-OPTIMA legacy analyzers can also communicate in CLI. The physical communications interface is RS-485.

Is Ethernet communications available?

No, native Ethernet is not available on the GRIDSCAN, but the serial communications can be converted to Ethernet with an external device.

Is a wireless solution available?

We currently offer the Sentinel as our wireless IoT solution. This device uploads the GRIDSCAN data to our H2Cloud dashboard.

What other data output format can be used with the GRIDSCAN, HY-ALERTA and HY-OPTIMA series?

Aside from either Modbus RTU or DNP3 data formats, an analog output can be used. H2scan offers an analog output solution for the GRIDSCAN series with the GSAO-1, GSAO-2. Analog output solutions for the Gen 5 HY-OPTIMA and HY-ALERTA series utilize the HYAO-1.