General Questions:

Q: Whats is the difference between the VPE and the VPE-1000?
Q: What is the difference between the VPE-1000 and the VPE-2000?
Q: Can AccuTrak detect leaks underground or through walls or insulation?
Q: Can AccuTrak® detect vacuum leaks?
Q: How often do I need to calibrate my AccuTrak®?
Q: How can I record audio from my VPE 2000?
Q: How do I check if my VPX-WR is in Spec?
Q: How does adjustable sensitivity work?
Q: Do AccuTrak® Instruments use or include any toxic substance?
Q: How do I grease a bearing with the VPE-2000?
Q: All Contact Probe Questions

Application Questions:

Q: Is AccuTrak® appropriate for natural gas leak detection?
Q: Is AccuTrak® appropriate for testing new installations of Natural Piping for leaks?
Q: Is AccuTrak® appropriate for testing tires and valve stems for leaks?


Q: Whats is the difference between the VPE and the VPE-1000?

A: The main difference is the VPE-1000's digital readout which you can use to trend results such as bearing and gear wear. The VPE-1000 comes standard with a noise cancelling headset that covers the ear to block out background noise. The VPE has a 10 element bargraph – the VPE-1000 has a 20 element bargraph and 4 element alphanumeric LED. Unlike the VPE, the VPE-1000 features a dedicated sensor for the touch probe providing significantly better detection capability in touch probe applications. covers 5 significant advantages to the VPE-1000 compared to the VPE. This Video covers 5 significant advantages of the VPE-1000.

Q: What is the difference between the VPE-1000 and the VPE-2000?

A: The VPE-1000 has one frequency band for each sensor – 36 kHz to 42 kHz for  airborne and 18 kHz to 22 kHz for the touch probe.
 
The VPE-2000 has two frequency bands for airborne – 28 to 32 kHz and 36 to 42 kHz and three frequency bands for the touch probe – 18 to 22 kHz, 32 to 44 kHz, and sonic 30 Hz to 6 kHz,  which allows you to inspect and hear sounds like the running of condensate in a pipe from a steam trap. The VPE-2000 also comes with a 5 piece, 3 foot extension probe and a padded belt back.

Q: Can AccuTrak® detect leaks underground or through walls or insulation?

A:We have had customers tell us they have been successful finding these types of leaks with AccuTrak® (when underground leaks were about 2 feet down and additional pressure was added), HOWEVER, the AccuTrak® was not designed to do this, and we can’t guarantee it will always be effective.  Remember, AccuTrak® works on sound, so the leak must be quite large for its sound to penetrate solids like sheet rock, insulation or soil and concrete.  There are other instruments on the market which detect LOW frequency sound, and were designed for these types of applications, however the same problems seem to exist even with these types of instruments.

Q: Can AccuTrak® detect vacuum leaks?

A: Yes, see Detecting Vacuum Leaks

Q: How often do I need to calibrate my AccuTrak®?

A:The AccuTrak® instruments are designed in a way to minimize the need for regular calibrations. They are constructed with components of very tight tolerances, and do not age rapidly. If there is a need to know for sure that the instrument is consistent with manufacturer specifications, you can elect to have the unit calibrated on a schedule of your choosing, however regular calibrations are not required.

Q: How can I record audio from my AccuTrak® Instrument?

A: You can hook up any AccuTrak® instrument to a digital recorder that actually time stamps the record you make.  All you need is a headset splitter and a cable available anywhere to record. Then you can hook it up to an analyzer or computer. Olympus makes a very good recorder, small and inexpensive that can record up to 3 hours.

Q: How do I check if my VPX-WR is in Spec?

A: To see if a WR is in spec, use a sound generator facing away from the WR. Use the horn restrictor on the WR. Connect the output cable to the WR and plug the other end (the BNC) in a vibration analyzer or a frequency meter. The frequency should be 2000 Hz +/-50Hz.

As for the sensitivity use a dusting spray can 20 feet away and make it spray a little not full stream, you should be able to detect it.

Q: How does adjustable sensitivity work?

A: If you have a set sensitivity it is like having a yard stick instead of a measuring tape. You can measure the length of a 2X4 with the yard stick with low speed and accuracy, or you can use a tape that is fast and accurate. In the case of the AccuTrak® you have a measuring tape that depending where you are with the sensitivity, is like having a tape that you can extend or retract to fit your needs. If you are doing compressed air leak detection you walk into the area and set the sensitivity (up or down) so that you get 2 to 5 LEDs. (If the area is quiet you may not get any LEDs) This setting is your background. Anything above this level indicates a leak or other ultrasonic sound.  Following this sound and letting the intensity guide you will eventually find the leak. However as you get closer to the leak the intensity will increase (this is the reason that you cannot tell how much a leak is leaking because you measured it in db or any other unit) and you may run out of “stick” i.e. max the display. At that point you lower the sensitivity, which reduces the display indication which in turn allows you to continue getting closer to the leak until you get right over it.

Having the ability to select the sensitivity and having the ability to change the volume in addition to that gives you flexibility to adapt in any situation.

more on sensitivity...

Q: Do AccuTrak® Instruments use or include any toxic substance?

A: None of our instruments contain any toxic substances. The battery should be disposed of in a proper manner, the same as any other standard alkaline batteries.

Q: How do I grease a bearing with the VPE-2000?

A: See How to Grease a Bearing with the VPE-2000.

Q: Is AccuTrak appropriate for natural gas leak detection?

A: The ability of the AccuTrak® to detect a leak is dependent on the amount of ultrasonic sound created by turbulent gas flow. This is determined by several factors including the size of the leak, the pressure or force of the gas which is leaking, and most importantly, the actual shape of the orifice itself.  

Although technically ultrasonics will work,  because of the potential hazards of natural gas leaks, we do not recommend the ultrasonic detector as it is not an absolute test. Also, our detectors have not been rated intrinsically safe.

Q: Is AccuTrak® appropriate for testing new installations of Natural Piping for leaks?

A: Yes, Assuming piping is exposed, and you are doing a standard pressure decay test with compressed air at around 30 PSI, pressure drops as small as ¼ PSI per Hour can be reliably detected and located. At higher pressure even smaller leaks can be found. Very small leaks of 1 PSI per DAY or less will be hard to find.

If the leak may be behind a wall (closed in) it is much more difficult to find. In this case use higher pressure (100+ PSI), and you may only find larger leaks (1+ PSI / hour).

All flammable gas pipe testing should be done with compressed air, for safety.

Q: Is AccuTrak® appropriate for testing tires and valve stems for leaks?

A: In regards to testing tire rims for leaks, the AccuTrak® VPE should work well, depending on leak size and location.  Because the geometry for a tire leak or rim leak is quite variable - you are dealing with a soft material, and you don’t know where to look for the leak - a small leak can be hard to find.   On a car tire, at 30 PSI you can find leaks as small as 1 PSI per WEEK.  On a truck tire at higher pressure, you can find even smaller leaks.

Valve stems make a lot of ultrasonic noise when they leak, and you know the exact location to listen, so you can find very small leaks. On a car tire, at 30 PSI you can find leaks as small as ¼ PSI per WEEK.  On a truck tire at higher pressure, you can find even smaller leaks.