There can be a number of things that can cause this issue to occur.
- Check that the DM32 gauge is working properly. Power it on and make sure everything functions manually.
- Check that you have set the Network to the correct setting for your wiring (Network Status :Wired, Network Status: WiFi Create if you are using the DM32 hotspot, Network Status: WiFi Join if you are joining a different hotspot, Network:Disabled for use with USB)
- If you are using WiFi Join, make sure that your computer's WiFi is also using the same network that the DM32 WiFi has joined.
- USB Hardware:
- USB Cable: The USB cable may not be working properly. Try using another USB to see if the DM32 is now detected.
- USB Port: The USB port may not be working properly or may not be providing enough power on your computer. This is especially true in laptops and tablets. Try to plug your DM32 into another USB port
NFPA and ISO do not certify any equipment or software directly. They are simply a standards writing body who takes input from the industry. In the case of hold time calculation and peak pressure evaluation the input from the industry was primarily from Colin Genge the CEO of Retrotec who wrote the original NFPA Enclosure Integrity Procedure for NFPA in 1984 and has been the only force in making changes to the Standards ever since. As a result, Retrotec training certification is accepted across all equipment manufacturers, end users in over 60 countries.
Colin Genge is used as a resource by Siemens, Tyco, Kidde, Ansul, Chemetron, Janus, Fike and 3M. If there is a question about enclosure hold time or peak pressure, he is the one who answers it.
One question we get a lot is about leaking flex duct that connects the ducTester to the return. We have tested the most ripped up flex available in our warehouse; it had way bigger pinholes and it measured 0.68 CFM at 25 Pa. When you measure a typical leakage of 100 CFM at 25 Pa or more, this is not even 1%. So we believe it is not worth spending money on replacing.
Uncertainties of results are affected by how "stable" or reproducible your measurements are, when all your data are analyzed collectively. They are determined through statistical analysis. If you would like to see these equations, you can look up the Standard you are testing to.
What FanTestic software does, is it graphs your measurements (technically speaking: on a Flow vs Induced Pressure, log-log axis) and a bestfit trendline is generated between these multiple points. The closer your measurements are to this trendline, the lower your uncertainties. The further away your measurements are from this trendline, the higher your uncertainties.
To minimize uncertainty, it is best to take more measurement points (both target and baseline points), minimize Baseline/Bias pressures (e.g. by dampening wind, etc), take target measurement points over a larger range of induced pressures, and take measurements on each target point for longer time.
Consider the following:
- Connection range lowers when the DM32 gauge is under low battery power. The voltage goes from 4.2V down to 3.3V and the signal strength output is slightly reduced. If you are having connection troubles and can only connect within a few feet, you should first check if the battery level is in the ‘red’; if so, charge the DM32.
- You may have an older version of GaugeRemote installed – make sure your Andriod or iOS device is updated to the latest. There have been improvements in the most recent versions to improve reconnection.
- Some mobile platforms’ ROMS have issues with their WiFi connection (something Retrotec cannot control). For example, the recent iOS 8.0 had WiFi issues and Apple had to push a fix out for 8.1, and then subsequently 8.1.1 for further patching. Go into the Settings of their mobile device, check its version number, and make sure it’s runn
What is an extrapolated result? (e.g. Q4)
Why is an extrapolated result different in FanTestic than on a DM32?
Q4 is a Flow result that is extrapolated to 4 Pa. For extrapolation of what the result would be at 4 Pa, a best-fit line on a graph (with a known slope) is needed.
The slope value is different for different enclosures, since the slope is dependent on enclosure leakage. To generate a line on a graph, you will either need to:
- Measure multiple points of data to compute a slope ('n' value), or you
- Guess a slope ('n' value)
FanTestic performs #1, whereas your DM32 performs #2.
In other words, FanTestic software records multiple measurements to cre
Checking with Microsoft Windows Click Once Installer information, the error message you are receiving tells us the following:
"These are generic error messages that occur when the application cannot be started, and no other specific reason can be found. Frequently this means that the application is somehow corrupted during download, or that the ClickOnce store is corrupted."
So it would seem that some of the files did not download correctly or that your ClickOnce user store may be corrupted.
Go to your Control Panel and Uninstall FanTestic. If you get a message box asking if you want to roll back to a previous state or to Uninstall, choose the Uninstall option. Then restart your computer. If there are any FanTestic shortcuts left on your desktop, you will need to delete them.
Install the latest version from the website:
Restart your computer.
If after the install
Why is there a reference pressure for EqLA results?
(Or Flow, Permeability, ACH results?)
The results are all referenced to a single pressure, the reference pressure. The reference pressure is dictated by the standard with which the test is trying to comply.
Induced building pressure is directly proportional to airflow rate through a building, and EqLA is directly proportional to airflow rate; so that a higher induced building pressure would be a higher EqLA. Hence, there needs to be a reference pressure when referring to a leakage or flow result.
For the ASTM standard, the leakage result is required to be at a reference pressure of 50 Pa, whereas it is 75 Pa for the USACE standard. Reference pressure also applies to permeability (e.g. CFM/ft2) and air change (ACH) results.
If you have a DM-2 and want to connect to it using software such as FanTestic or the Retrotec Data Logger, you need to install a USB Driver.
Check your Windows operating system version to determine if you need a 32 bit installer or a 64 bit installer, and download and install from the website.
If you have a DM32, you should use the WiFi or Wired Ethernet connection to the computer for controlling the gauge. The only time you need to connect the DM32 to the computer using the USB is when updating the gauge firmware using the DM32Configurator software . You can use the USB for gauge control but it is not recommended. In any case, the DM32 USB driver is automatically installed by FanTestic.
If you look in your Control Panel - Programs and Features section, you will see the USB drivers that are installed on your computer, listed under Retrotec as the publisher.
For reference to equations for calculating results from a Blower Door test, you can refer to the ASTM E-779-10 standard.
In engineering (fluid dynamics) terms, Bernoulli's equation is an energy balance equation that assumes incompressible fluid (e.g. air) at steady state through two points (e.g. through a building); The equation can be simplified to an orifice plate equation and applied to a Blower Door test. We can calculate point #1 - the total leakage (EqLA or ELA) of a building, and point #2 - a known area (size of fan hole: Range configuration) by measuring via Blower Door system the airflow rate through these points at a specific induced building pressure (the reference pressure).
Induced building pressure is directly proportional to airflow rate through a building, and EqLA is directly proportional to airflow rate; so that a highe