TN268001 B, 11JAN26

DEC+ User Guide/FAQ

01. UPSIDE DOWN DISPLAY
It's not, but your phone might be: Nearly all smart telephones have the microphone at the bottom of the device, just like Bell's original handset did. Most things we do with a cell phone, we do with the mic pointing down. In this case, we get vastly better performance by pointing the mic toward the engine, and away from the user. When the app detects it's likely running on a telephone, it displays such that the text is right-side up while you point the microphone at the engine. This behavior is un-necessary with a desktop PC and most tablets, so on these devices, the interface displays in a "normal" orientation. 

02. USAGE PROCEDURE
Stand 1-3 feet away from the engine, with a clear line of sight to it. If possible, warm the engine to operating temperature. Load the app on your device, point the microphone at the engine while it runs at low idle (or as close as possible with permanently loaded engines like gensets), and press the button above the word "start recording". Press "stop" if you need to abort early for some reason. Under normal circumstances, just let it time out automatically, which it will do after 6 seconds. After a brief delay*, the analysis results will appear on-screen.

Internet access is required to use DEC+. In cases where the engine is hard to get a recording of, for example if it's hard to start and often stops running shortly after starting, we recommend trying a blank "test" recording before starting the engine, so you'll know that your device is able to talk to our computer when it needs to.

*This delay may be up to 30 seconds the first time you use DEC+ in any given hour, or any time the Internet connection is spotty.

03. COMPATIBLE DEVICES
It's designed for mobile smartphones, and works great with them. iOs and Android are both fine. It will work on *any* computer that has a user-viewable Web browser and a microphone- including Windows PCs, Macs, and tablets. Believe it or not, there are some valid use cases we have encountered where DEC+ can be of use on a PC. One of them is if people email you clips of engines, you can configure the PC to use the speaker output as a microphone input, and use DEC+ to analyze those clips.

04. OUTPUT FIELDS
Summary:
"Tap the record button..." (displayed at first load)
"Recording..."
"Analyzing..."
"Too quiet" (get closer to the engine)
"Too loud" or "too hot" (get farther from the engine)
"Signal too short" (try again without hitting the stop button. Just let it time out automatically.)
"Engine not detected"
"Engine detected"

Operating Condition:
"Not available" (displayed when no engine detected yet)
"Normal Operation" (no evidence of damage)
"Valvetrain Wear" (detectable level of wear in valves, cam, tappets, &c.)
"Short Block Wear" (etectable level of wear in rods, pistons, crank, or mains)
"Irregular Combustion" (imbalanced injectors, misfire, or exhaust leak detected)

Energy Loss Score ("ELS"):
0-10 scale of how bad the problem is. We look for evidence of kinetic energy leaking through paths not intended by the engine designer, and compare it to engines with known degrees of damage. "0" is no damage. "10" is "imminent failure". In general, scores between 0 and 2.5 are stable, reliable conditions. Scores between 2.6 and 7.5 are unstable conditions, but which are likely repairable. 7.6 and above are conditions that warrant removing the engine from service immediately.

Estimated pounds:
0-100 scale of the estimated pounds of any mechanical component that is associated with a mechanical failure. This output only displays when "Operating Condition" is "Valvetrain Problem" or "Short Block Problem".

05. ENGINE OPERATING STATE DURING TEST
Low idle if possible. So 400-800 RPM for most engines. Disconnect it from load if possible, if not, minimize the load as much as practical.

06. RESULTS INTERPRETATION
That's up to your professional judgement. This tool isn't meant to replace your expertise, but rather to augment it.
	So, for example, let's say you have a diesel engine that's had an  'awful tick' for years, 
that's never changed, but that worries you. The tool predicts "Valvetrain issue", and ELS of "2.0".You could reasonably conclude that this is one of the ~30% of diesel engines that just... *makes a noise* despite there being nothing wrong with it.
	In another example, suppose you had another engine that made an awful noise from the oil pan. The tool predicted "Short Block Problem", and ELS of "9.0". You could conclude that this engine should be removed from service and either replaced or remanufactured.
	In another example, suppose you had an engine that was making a strange noise near the head. The tool predicted an operating state of "Injector Problem", with ELS of "4.0". You conclude that you will replace the injectors in the field, and that no full teardown is likely to be needed.

07. HOW FAST SHOULD THE ENGINE BE RUNNING
Low idle. So 400-800 RPM for most engines. Disconnect it from load if possible, if not, minimize the load as much as you can.

08. WHAT KINDS OF DIESEL ENGINES WILL THIS WORK WITH
Nearly all of those you may encounter, but there are some exceptions: It will not work with inline 2-cyliner engines, or any others with an uneven firing order by design. It does not work with most multi-cylinder, low-speed diesel engines, the parts of these engines are too far apart for one microphone to make sense of them all.
	Note that 1-cylinder engines *are* even-firing, and DEC+ works with them, whether low- or high-speed. DEC+ also works well with medium-speed engines.

09. RECORD BUTTON NOT WORKING
Either microphone permission wasn't granted, or the device has no microphones. Or you made the error we frequently do on PC, and forgot to plug in any microphones.

10. 'TOO QUIET' ERROR EVEN WHEN CLOSE TO ENGINE
In most cases, there is some physical problem with the device or its microphone. We frequently find that wads of grease get stuck in the mic hole and cause this. So check for dirt in there. Otherwise, send yourself a video taken from your phone, and see how well the audio plays back- if it's muffled, then so is the audio DEC+ is hearing.

11. HOW IS THE 'ENERGY LOSS SCORE' USED
Energy Loss Score ("ELS") is the measure of how much energy is involved in any mechanical issue identified. For example, a severe rod knock involves significant kinetic energy. An improperly adjusted valve involves very little. In general, as the degree of energy loss due to a problem increases, the likelihood of a successful in-field or in-frame repair falls. The ELS is intended to aid decisions about what to do with the engine and how likely it is to fail soon. By taking readings at different times, ELS can also be used to determine whether the engine condition has changed over time. It does NOT correlate with any changes in the output of the engine as measured at the flywheel.

12. PROGRESSIVE WEB APP
DEC+ is distributed as a 'Progressive Web App', which enables us to provide a consistent experience across all platforms; mobile, PC, and otherwise. DEC+ also works as a normal web page- visit solanum-service.com/dec to use it. 'Installing' the app is solely for the convenience of having it on the home screen.