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Audible warning system?

Audible warning system?

Audible warning system?

(OP)
I work for a company that rents and sells pumps and we've been discussing trying to incorporate some sort of audible warning system for when something goes wrong with one of the pumps. We actually have a system in place that alerts us when something goes wrong, but no audible alert.

I know greeting card companies have little players in their cards, I was thinking about incorporating something like that into one of our control panels. I'm thinking this might be a relatively cheap and simple solution.

I'm a mechanical engineer, so I only have a very basic understanding of the electronics and wiring.  Can any of you offer any advice on what I might consider using and how difficult this would be to implement?  Thanks.

RE: Audible warning system?

There are tons of audible signalling devices driven by all sorts of electrical signals/voltages,etc...

More information on your current "warning system" that you have already for alerts is required to answer this question.
How do you get a warning now..?
Voltage.. contact closure..etc..

RE: Audible warning system?

How loud is the pump?  If it's fairly quiet, Radio Shack sells "doorbell" type buzzers, all you do is apply power.  A relay connected to your current signaling system would apply power to the doorbell when the current system went off.  It would cost you about $5 and be super-easy to put together.  If you need something louder or long-term buzzing, there are some slightly more complicated methods...

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Audible warning system?

(OP)
mcgyvr,

I don't know. I'll have to research and get back to you on that.

macgyvers2000,

Most of the pumps are pretty loud. What I was thinking was more along the lines of some pre-recorded voice prompts that we could use. Would that be more difficult?

RE: Audible warning system?

(OP)
Actually, I was thinking the voice would only activate to warn of problems.  A few voice commands to warn of a few specific problems.  This would likely occur when the pump is not running, so noise would not be an issue.

RE: Audible warning system?

Are you looking for some off-the-shelf box or do you have the budget and time to have someone develop something from chips?  Is this something that is high-volume or are we talking about a one-off design?

Glenn

RE: Audible warning system?

Sonalert (now www.Mallory-sonalert.com) beepers are quite standard. Many interesting sounds to choose from these days.

You'd probably want a 'silence' toggle swith in series with the beeper, but not the flashing light. A 'test' button is also pretty much standard (best if wired up to the sensor side to test the entire system end-to-end).

 

RE: Audible warning system?

and make sure this "silence" toggle will automatically be turned back on when there is no more warning signal.

Nothing worse than finding out the pump is bad and you never knew because the last service guy left the silence toggle on so you never heard the audible warnings.

RE: Audible warning system?

That added feature can be done with a latching relay. The silence switch would be a push button to activate the relay. Once the alarm passes, the relay will fall-back to normal.

 

RE: Audible warning system?

(OP)
geekEE,

Would prefer something off the shelf.  And it would be a high volume application, I would like to implement it assuming it works well.

RE: Audible warning system?

Quote (nocam1334):

This would likely occur when the pump is not running, so noise would not be an issue.
Then there's no reason the simple buzzers wouldn't work.  You can buy them in bulk from Digikey/Mouser, add a relay and some wire and you're done with it.  You can have different buzzer tones for different warnings.  Adding voice means a more complicated circuit.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Audible warning system?

(OP)
macgyvers2000,

I agree, but I'm still leaning towards a voice system simply for the novelty factor.  It would be cool to have a talking pump.

How much more complicated would the circuitry have to be?

RE: Audible warning system?

You would need a micro-controller with a voice synthesis chip. Then you look at various inputs to output your various messages.

You, of course, need a circuit board and whatever terminations you desire built on to it.  You would need a power supply to run the circuitry.

Per unit price for just a running circuit board would be something like $30~50 per 100 pricing, depending on speakers and other niggling details.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Audible warning system?

Well the greeting card voice modules are probably all made in China. Here are some examples:
http://www.alibaba.com/product-gs/207610216/voice_recorder_module_for_greeting_card.html

http://www.tradeeasy.com/manufacturers/electronic-parts/recording-modules.html

http://www.sound-led.com/html/catalog_140.html

The quality is not so good and the volume is low, but if you have large quantities, they're probably inexpensive.  I doubt that any of these things are made for industrial environments though!

Glenn
 

RE: Audible warning system?

For something really cheap, connect a cheap MP3 player board to a microcontroller and some cheap audio amplifier, like LM386 or something like that.

The uC could interface the MP3player pushbuttons, emulating the file browsing/playback button sequences.
 

RE: Audible warning system?

(OP)
GonzaloEE,

I like that idea. I checked on MP3 player boards online and the price varies wildly (from $25 to over $200). Any you could recommend in particular?

And what do you think would be the total cost of making something like what you suggested?

RE: Audible warning system?

Hacking a micro, buttons, aplifier, etc. to an existing design (MP3 player) just sounds like a bad idea and should rarely be done with any high-volume product.  Your player source could quickly dry up, they could change something in the design that might fail (imagine how pissed off a customer's going to be when a pump fails because one of your "voice" warnings never played, or the wrong warning played because it was a different MP3 track), and so on and so on.

Don't make this more difficult than it needs to be just because of the gee-whiz factor.  If I was in the field and a pump failed, I don't want Majel Barrett's voice (Star Trek anyone?) telling me I have 10 seconds to leave the area before it explodes, I want a dependable fail-safe system that shuts the pump down and blinks a light on a control panel telling me what happened.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Audible warning system?

(OP)
macgyvers2000,

I don't disagree.  The reason I'm looking into a voice system is because it is a request of my boss. We do have safeties in place. He just wants to add an audible voice, mainly for the novelty factor. I don't necessarily agree that it will be a good idea, but I am looking into it nonetheless.

RE: Audible warning system?

Over the years I have seen many fools use an off-the-shelf product inside another product.  Most recently an OTS camcorder for a medical arthroscope.  In all cases I've seen it was a disaster.  I mean a giant pile of steaming cr@p disaster.  I have been temped in the past to do the same but luckily always didn't.

Have you bought shoes lately?  You can't go out and buy the same pair two months later.  That model shoe is gone forever and a new model has replaced it.  Now consider an electronic consumer gizmo!  They change even faster.

In the previously mentioned arthroscope. They had an order for something like 200.  So they bought about 210.  They got thru about 160 but had so many issues that they had about 40 rejects.  They went to buy replacements and couldn't!!! They no longer existed even though they'd got them from Amazon.  Last I heard they were trying to find some on Ebay and the customer was livid.

You should just roll your own.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Audible warning system?

nocam1334, right now, I have no idea how much would it cost, but considering your audio amplifier won't be like Hi-Fi, you may try with lower bitrate MP3 for a smaller memory usage. For example, a 2sec. voice message recorded at 128kbps (CD quality) needs some 32KB of memory space, though at 32Kbops you get decent AM radio-like quality, or telephone at 11Kbps.

OK, just in case these cut&paste design 'procedures' are hurting some basic Engineer's principles :) I'd suggest to make an embedded board with some midrange processor/DSP/etc, SD-card or on-board flash, and some integrated audio stage.
  
Of course you'll have to build the firmware for MP3 decoder, or interface the CPU to some MPEG L3 decoder chip, etc. Also, you have to define how to upload your files: CPU-interface, USB + file system to load files from your computer, etc.

If you're going for the 'hack & paste', check in advance which bitrates your player support.  There are plenty of WAV2MP3 conversion s/w on Inet if you're going for a more decent, embedded solution.

Good luck!

RE: Audible warning system?

If you must create a bespoke solution and the device is going to have a one- or two-word vocabulary, then skip MP3 and all that and just have it spew out a simple wave file on command. The wave file is likely smaller than the MP3 routines. With some clever programming (using PWM) the audio stage might just be a digital output pin connected to a series capacitor and the speaker.

 

RE: Audible warning system?

I heard of a college mate who made a simple audio file player with something like what VE1BLL suggested.  He downsampled a WAV file with MAtLab to match the bitrate to his uC clock speed.  Then made a simple PWM program with pulse widths directly taken from WAV sample values.  The rest was just wiring: a RC filter and a walkie-talkie audio amplifier IC.
Sound was horrible, like robotic, but you could tell the messages.

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