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As the picture to the left shows, the locking flats are only located at the base of the nose ring. The locking flats do not extend up the side of the nose threads. For a vast majority of applications, the locking flats do not need to be used. If the knurled nut (not shown) is properly tightened, the alarm will not move in the application. However, for some high end applications with a lot of vibration (such as aerospace), the locking flats would help to ensure that the alarm will not rotate within the panel which could end up putting pressure on the wiring connections to the terminals of the alarm. |
A: Mallory's speakers do not have any mounting holes. Customers typically mount the speakers by laying the speakers on a ledge or into a housing that does not touch or obstruct the mylar cone material and then either use glue or silicone adhesive to secure the speakers to the housing or ledge. Also, care must be taken that the glue or silicone adhesive does not get onto the mylar cone material which could dampen the sound level.
A: No, the bare speakers are not offered standard with wires. However, Mallory can provide wires and cable assemblies with the speakers upon request. Click here to be directed to our contact information page.
A: Yes, but the alarm will be attenuated 15-20 decibels. This means that the sound level will be about ½ to ¼ as loud as it would be if it was mounted externally or if there were openings made in the enclosure so that the sound could radiate out. For a full discussion on mounting alarms inside of equipment, read the article titled, “Audible Alarm Use and Equipment Integrity Issues.”
A: Yes! Click here to be directed to our contact information page.
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A: 330ºC for 1.5 seconds or 270ºC for 4 seconds.
A: 270ºC for 3 seconds.
A: Users have found our alarms not to be the critical component for setting up the re-flow oven profile. Unless you deviate significantly from the profile recommended by the solder paste manufacturer or other component suppliers, you should not have any problems.
A: Unlike resistors, capacitors, IC’s, or other components, electronic alarms are actually a complex electro-mechanical
assembly. Unless you are using a transducer or buzzer unit that utilizes spring clip connections, there are usually
a multitude of solder joints internal to the audible alarm. If you put too much heat for too long of a time on the
audible alarm terminals, you can cause a variety of problems including:
1. The solder joint connecting the audible alarm terminal to the PC board may re-flow causing a cold solder joint.
2. Components on the circuit board near to the terminal may heat up and fail due to either thermal shock of the component or cold solder joints.
3. The solder plating on the terminals may fail.
A: It is only recommended to wash those audible alarms that are sealed in the back and have a wash label over the sound opening. Not all board mount audible alarms are available in this configuration, so it is recommended to view the part data sheet or call our technical support number for assistance (317-612-1000).
A: If the part does not have a wash label, the cleaning solution will get into the front of the part
through the front hole acoustic opening. This will not likely damage the part, but an audible alarm
will likely not sound (or barely sound) if there is liquid solution in this front chamber.
The cleaning solution may dry out over time on its own, or it can be removed more quickly by using
an air circulating oven. However, the time it takes for the part to dry out depends on many different
factors.
If the part is not sealed in back, several things may happen. The cleaning solution may get
trapped inside the part and may seep out over time or at an inappropriate time. If the part has a
circuit board, the cleaning solution may get up on the circuit board and cause electrical shorting and
possibly permanent damage to the part or the circuit board the part is mounted on. Finally, the
cleaning solution may cause corrosion internally to the audible alarm which could result in the part
failing catastrophically or slowly over time.
A: Yes! Click here to be directed to our contact information page.
Sound Issues Top
of Page
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A: Sound level is measured in decibels (abbreviated dB). The dB scale is an arbitrary scale that reflects the loudness of the sound that is being measured. It ranges from 0 dB (threshold of hearing) to 130 dB (threshold of pain). For a better understanding of the decibel sound level scale, see Technical Application Guide, "Decibel Sound Level Scale".
A: The audible alarm should be at least 10 dB louder than the ambient back ground noise so that it can be easily heard. You can estimate the ambient background noise by using the chart found on Technical Bulletin 06-03 or you can use a sound level meter to measure the actual ambient noise level.
A: Every time the sound level increases by 10 dB, it will sound twice as loud to the human ear. For example, an alarm specified as 90 dB at 2 feet will sound half as loud as one specified as 100 dB at 2 feet.
A: Sound level falls off over distance. We intuitively know this because we have to talk louder (or even shout) when people are farther away. The rule of thumb is that every time the distance doubles, the sound level drops off by 6 dB. For example, if an audible alarm measures 60 dB at 2 feet, by the time it reaches 4 feet, it will only be 54 dB. By the time it reaches 8 feet, it will only be 48 dB, and so on.
A:
Unfortunately, there is no one standard distance for specifying the sound level for audible alarms.
However, there are some common distances such as 2 feet (60 cm), 1 foot (30 cm), and 10 cm (4 in).
An excel spreadsheet has been developed to convert among the most common distances used.
The link for the spreadsheet is here:
Sound Level Distance Conversion Tool
For example, if you want to compare an alarm that is specified as 100 dB at 10 cm and one specified
as 88 dB at 2 feet, you must choose one distance that you want to use to compare the parts. Using
the distance conversion spreadsheet, you would find that 88 dB at 2 feet equates to 103 dB at 10 cm,
so the alarm specified as 88 dB at 2 feet is actually louder than the other one when they are compared
apples to apples.
A: Most people can only distinguish a sound level change only when it increases or decreases by 3 decibels. For example if a person was listening to an audible alarm that changed from 90 to 92 dB, that person would most likely say that the alarm did not get louder. If the sound level changed from 90 dB to 93 dB, the person would say that the sound level is slightly louder. If the sound level changed from 90 to 96 dB, the person would say that the sound level is significantly louder. If the sound level changed from 90 to 100 dB, the person would say that the sound level is twice as loud as before.
A: Pulsing tones are more easily distinguished than constant tones. Also, pulsing tones convey
typically convey more urgency to a person than a constant tone. On the other hand, it takes more
electronic circuitry to make a tone pulse, so pulsing audible alarms are usually more expensive than
constant tone alarms. If a more pleasant sounding tone is needed, a chime sound may be preferred.
You can listen to the various sounds that Mallory audible alarms make at this link:
Sonalert® Sounds
A: dB is the abbreviation for decibels which is how the sound level of audible alarms is measured. The “a” in dBa means that the sound level was measured on an A-Weighting scale. The A-Weighting scale was developed to compensate for the fact that the human ear is not a perfect microphone. By applying the A-Weighting scale to sound level measurements, you put the different frequencies (pitches) that the audible alarms produce on an even basis (i.e. comparing apples to apples). Mallory always uses A-Weighting for their sound level measurements, but not all audible alarm manufacturers are this diligent.
A: Yes. See Technical Application Guides, "Controlling Sound Level Mechanically" & "Controlling Sound Level Electronically".
A: Mallory Sonalert has worked with Professors at Rose Hulman University in an attempt to model the sound chamber using Helmholtz equations, but these equations do not work well in predicting the resulting sound characteristics of the alarm. When Mallory Sonalert engineering designs new audible alarms, we rely on past designs and experience to give guidance on a starting point. However, the final design of the sound chamber is based on careful process of building prototype after prototype in order to find that sweet spot in sound performance.".
A: The acoustic sound chamber of audible alarms includes the area inside the housing that is in front of
the sounder element and includes the front hole opening.
The sound chamber does not work like organ pipes.
In organ pipes, there are standing waves of different size depending on the frequency generated.
This is why the organ pipes are different lengths. If the standing wave principle was used for electronic
audible alarms, the alarms would have to be many inches or feet in length.
Perhaps the best way to explain how
the acoustic sound chamber works is to think of it using a more visceral medium. If you think of the air sound
waves being replaced by water, the sound chamber would work by providing an efficient shape for the water to move
out of the housing without being obstructed by eddies, reverse currents, and dead spots. Essentially, the acoustic
sound chamber provides a low impedance path for the air pressure wave to escape the housing with maximum intensity.
A: Yes! Click here to be directed to our contact information page.
Environmental Issues Top of Page
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A: Yes, all SC series alarms are sealed to ensure no rain, splashing water or dust will penetrate inside of the unit. When used in an outdoor application, the alarm should be mounted facing downward or no greater than horizontal. This will ensure that the nose cone of the alarm will not collect and/or hold water. To prevent water from penetrating behind the panel, use our ACC03 or SG1 rubber gasket accessories.
A: We have many
models that are
UL Recognized and
cUL Recognized.
For a complete list of those units contact Mallory
Sonalert Products, Inc.
SC, SCE, and VSB series Sonalert models, when fitted
with gasket ACC03, have been tested to NEMA 3R, 4X, 12;
cUL C22.2 No. 94; IP66. See our
UL or
cUL yellow cards
for details.
Mallory also has the
SCH Series which is approved for Class I Div. II
applications. See the
UL yellow card for this series.
A: UL Listed means that a piece of equipment has met the requirements spelled out by UL for that type of equipment. UL Recognized means that the individual component has met the requirements spelled out by UL for that type of component. The main difference is that equipment is UL Listed while components are UL Recognized. Since Mallory alarms are components, they are only required to be UL Recognized in order to be used in UL Listed equipment. Check Mallory's UL or cUL Yellow Cards to determine which alarms are UL or cUL Recognized and therefore can be used in UL Listed equipment.
A: The alarms, buzzers, transducers, speakers, and other products & accessories sold by Mallory Sonalert Products, Inc. are individual components that must be incorporated into final equipment in order to be useful. Since their safety and use depends to a very large extent on how they are incorporated, they are not covered by the various European Directives, and need not be CE marked. In fact, per the Low Voltage Directive, components must not be CE Marked. See our CE Marking statement here: Mallory CE Statement
A: For Mallory SBM, SC, SCE, SNP, & ST Series, the individual components used in the alarms models all meet a flammability rating of UL-94HB or better, so these alarms will pass a UL-94HB test. However, no specific flammability testing has been done on these or other Mallory alarms models.
A: Mallory Sonalert has been supplying audible alarms to the aerospace industry for over 30 years, and customers include nearly all major and minor jet, airplane, and helicopter manufacturers. All the various alarm models used in these applications have been certified with the FAA by the alarm user, and while Mallory has not been directly involved with the FAA during the PMA (Parts Manufacturer Approval) process, Mallory has (and will) supply all needed information for any certification and/or approvals that are required by the application.
A: Mallory is not aware of anyone who has ever had a shelf life issue with our alarms. That being said, some alarm models contain aluminum electrolytic capacitors. The recommended shelf life for these capacitors is 5 to 10 years depending on how they are used. Our application of these capacitors is not especially sensitive to the shelf life issues of these components, so we would expect that they would last 8-10 years or longer in our alarms just sitting on the shelf (no voltage applied during that time).
A: For the SC/SNP/SBM series, many of these models are approved to UL-464 which
uses the following Hi-Pot test: 1240 Vac for 60 seconds with the part wrapped in
aluminum foil.
The electrical connection for the test is between the terminals and the foil.
The models in these series that are not UL approved would also pass this test as
they are similarly constructed. For the other board and flange mount parts that
we offer, no dielectric/hi-pot testing has been done to date (please contact us
if this test is required for your application).
A: Mallory SCH series of panel mount alarms are approved to Class I Div. II groups A, B, C, &D as well as being NEMA 4X approved. Here is the application guide discussing these models: SCH Series
A:
MTBF data has only been generated for the SC, SNP, and SBM Series. Historical life test
data at maximum temperature and voltage has resulted in the following failure rates for a majority
of the models in these series that we sell when calculated per Mil-Handbook-217:
F.R. = 0.08% per 1000 hrs @ 60% confidence level
MTBF = 1,250,000 hrs @ 60% confidence level.
A: Customer returns of Mallory audible alarms for failure to operate are very rare. Of the few parts returned each year, the vast majority of the root cause of failure is an over-voltage or voltage spike condition caused by the customer’s application. For more details, see Technical Application Guide, "Typical Failure Modes".
A: For our Rugged/Military panel mount models, these alarms are already at the limits of the technology. However, it is likely that our other alarms will work at colder temperatures. Please call and ask for technical support to see if the alarm you have in mind is capable of working at colder temperatures.
A: Design Engineering uses a variety of tests during the verification and validation design phases. These tests can include: surge voltage, reverse voltage, hot & cold life tests, room temperature life test, humidity, vibration, shock, salt spray, and terminal strength. For more details see Technical Application Guide, "Environmental Tests".
A: Mallory SC, SCE, VSB, & SNP series of panel mount alarms are fungus inert and resistant. The housing material is 6/6 nylon, the knurled nut is made of either 6/6 nylon or anodized aluminum, and the sounder element is either brass or stainless steel.
A: MSL 1 (Unlimited)
A:
Five samples of our panel mount part
SC628 were submerged for 100 hours at room temperature in a 6000 ppm
formaldehyde/Water solution. All 5 parts were visually and electrically
acceptable after testing. All SC & SCE parts have the same external construction,
so based on this testing, all parts in these two series are resistant
to formaldehyde.
A: Yes! Click here to be directed to our contact information page.
A: The seller warrants the goods to be supplied hereunder will conform to the pertinent specifications, drawings and approved samples, if furnished, and that such goods will be of good materials and workmanship and free of defects if properly installed and used as sold by Seller. If within one-year period from the date of shipment to Purchaser such goods, not having been subject to misuse, alteration, modification, neglect. Improper installation or unauthorized repairs not exposed to an abnormal environment, are shown not to be in conformity or are shown to be defective in workmanship or materials, Seller’s sole and exclusive obligation under this warranty is to repair or replace such goods, provided return is made prepaid to Seller or its designated representative with the following tagged information: (i) date of shipment of such goods to Purchaser; (ii) date such goods are determined to be non-conforming or defective; and (iii) specifying the apparent non-conformity or defect. No claim will be allowed under this warranty unless Purchaser notifies Seller of such claim within 30 days after Purchaser learns of facts giving rise to such claim. Purchaser’s failure to test, inspect and make claim within such one-year period shall be conclusive evidence that the goods shipped were satisfactory in all respects. The liability of Seller under the forgoing warranty shall not exceed the price charged by Seller for the goods which give rise to the Purchaser’s claim. THE AFORESAID WARRANTY IS EXCLUSIVE AND IN LIEU OF ALL OTHER WARRANTIES WHETHER EXPRESS OR IMPLIED (INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR PURPOSE), EXCEPT OF TITLE. SELLER ASSUMES NO LIABILITY FOR ANY SPECIAL, INDIRECT, CONSEQUENTIAL, INCIDENTAL OR OTHER DAMAGES OF ANY TYPE (INCLUDING, BUT NOT LIMITED TO, DAMAGES RELATED TO LOST SALES AND PROFITS, EXCESSIVE OR INCREASED COSTS AND EXPENSES, FIELD RECALL AND RETROFIT, COSTS AND EXPENSES , DOWNTIME COSTS AND CLAIMS OF CUSTOMERS OR PURCHASER FOR SUCH DAMAGES) RESULTING FROM NON-CONFORMING OR DEFECTIVE CONDITION OF ANY GOODS SOLD BY SELLER TO PURCHASER HEREUNDER, AND PURCHASER ASSUMES ALL LIABILITY FOR ALL CONSEQUENCES ARISING OUT OF ITS USE OR SALES OF SUCH GOODS. THE AFORESAID REMEDY OF PURCHASER IS EXCLUSIVE AND THIS LIMITATION OF LIABILITY PROVISION SHALL APPLY TO ANY AND ALL CLAIMS OR SUITS BASED UPON NEGLIGENCE, BREACH OF CONTRACT, BREACH OF WARRANTY, STRICT LIABILITY, OR ANY OTHER LEGAL THEORY UPON WHICH LIABILITY MAY BE ASSERTED AGAINST SELLER BY PURCHASER OF OTHERS.