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Old December 9th, 2007, 12:49 AM   #1
deroos
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tattle tale

Do any of you guys remember a trouble shooting aid called the tattle tale? it was to be wired in paralel to a suspect switch so if that switch opened the voltage would go through the tattle tale and it would burn open so you knew that switch did in fact open. I had a problem with a boiler a while back, and had to narrow it down from about five saftey devices. some of these would have come in handy. Do you know of anything similar being sold today?
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Old December 9th, 2007, 01:57 AM   #2
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never heard of it... sounds like blown fuse indicator...
could this be it?
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Old December 9th, 2007, 08:12 AM   #3
geniusintraining
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I have one... (I think)

I never used it, but I had the same issue with a safety chain circuit so we bought one off of eBay, before it showed up in the mail the issue was resolved.

It was hard to find, send me your information and I will mail it to you but it will not be until Wednesday, when you are done you can mail it back... info@plctrainer.net

IF we still have it... I have not see it for a while and the great "5's" have made many of my tools go bye bye

Let me look when I get back and I will let you know (I just serched eBay and nothing)
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Old December 9th, 2007, 08:16 AM   #4
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We have some at work if you want a manufacturer or part number.

Gary
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Old December 9th, 2007, 10:25 AM   #5
Ron Beaufort
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it's been years since I've seen one, but (in a previous lifetime) I used them to troubleshoot large AC compressor circuits which had a large number of interlocks wired in series ... (high pressure, low pressure, low oil, etc.) ... the style I remember was a little plastic cube with two pigtail leads coming out of the bottom ... when a voltage was applied across the leads, a link would burn through and a bright red flag would pop up into the cube ...

I've also heard of using a fuse with a VERY LOW current capacity to do the same trick ...

if you can't find them anywhere else, try checking with a well-stocked heating and air-conditioning supply house ... that's where I used to buy mine ...

PS Edit ... Gary ... if you can, please go ahead and post that info that you mentioned ... I'd like to have that for my "just in case" files ...
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Old December 9th, 2007, 10:34 AM   #6
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Ron,

The A/C shop is the ones that purchased them. I will post a reply tomorrow morning when I get to work.

Still having a great time reading your post as always.

Gary
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Old December 9th, 2007, 07:30 PM   #7
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You can do the same thing with a relay that has a manual operator and a visible indicator.

Wire to a normally open contact from the relay in series with its coil.

Push the manual operator in and it will stay energized until power drops out.

I used to have 6 of them on a din rail with a magnet base and alligator clips on the leads so I could test up to six points in a series circuit at once.

Someone at work called it a tattle-tale relay:

CR1 CR1
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Old December 9th, 2007, 07:38 PM   #8
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Very good idea Paul...

The only thing I don't like about these and Ron's fuse idea or any other for that matter, is these are Safety circuits we are messing with.

What ever you use, buy one or roll-er own, you need to make sure that the logic (wiring) is not going to be by-passed with the device..

Just something to think about

Damn where's Ron... he would of been all over this
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Old December 9th, 2007, 07:57 PM   #9
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My application was a rubber calendar line controlled by reliance dc drives with a single channel old-school standard relay e-stop circuit with 6 belly bars, 8 rope safeties and about ten pushbuttons wired in series.

Most of the segments were available upstairs in a locked electrical control room. I was more than confident that adding an alternative load to the circuit was a much safer approach than the tried and failed method of jumpering out sections of field devices.

It took two days and three occurences to find the pushbutton with a corroded contact and the bouncing contact in the Namco rope switch with the tattle tale set-up.

This problem occured about once every 4 to 36 hours, and created a more dangerous situation for the machine tenders who had to clean all the rubber off this 300' process line, and start it all back up.

I later used the setup for a run circuit on a bead extruder that had only a few devices.

Later I wrote a ML1000 program called "Trap_PC" that would allow you to detect either change of state of up to 8 (IIRC) inputs very effectively.

I designed it to be faster than the relays, and set the corresponding output to the first one that changed states.

I used that to troubleshoot relay logic where everything had dropped out by the time the fault occured.

I might have that little Golden Nugget of a program still...
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Old December 9th, 2007, 08:04 PM   #10
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from my distinguished colleague geniusintraining:



Quote:
The only thing I don't like about these and Ron's fuse idea or any other for that matter, is these are Safety circuits we are messing with.

What ever you use, buy one or roll-er own, you need to make sure that the logic (wiring) is not going to be by-passed with the device..




absolutely ...



of course ANYtime you do ANYthing to a circuit you run some amount of risk of defeating a safety feature ... no argument there ... but the method that we’re talking about is to use something like a 1/8 amp fuse (or preferably less) in a circuit that pulls in something like a 1.0 amp contactor coil ... IF (big IF) it’s properly sized and connected, the tattle-tale fuse won't defeat the safety switches in the circuit ... so the contactor still drops out ... but ... the advantage is that now we know WHICH SPECIFIC ONE of the many safety devices caused the contactor to drop out ...



the case that I used this approach on was at a large convention center at a resort island that I used to work at ... the A/C compressor would occasionally shut down for no apparent reason - usually right in the middle of a big conference or wedding party ... think: 99 degrees F ... 99% relative humidity ... very unhappy guests ... by the time someone got up on the roof, all of the equipment’s pressures and temperatures had settled down ... no one could ever isolate exactly which of about seven or eight components in the contactor circuit had caused the problem ... the tattle-tales did the trick ... come to find out, it wasn’t actually a real “problem” - just an intermittently defective pressure switch ... specifically, the pressure was always ok - but the switch would flake out from time to time ...
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Old December 10th, 2007, 12:14 AM   #11
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Quote:
Originally Posted by OkiePC
You can do the same thing with a relay that has a manual operator and a visible indicator.

Wire to a normally open contact from the relay in series with its coil.

Push the manual operator in and it will stay energized until power drops out.
I still have 10 relays of that sort OkiePC describes on a din rail with alligator clips on the leads so I could test all the series circuit all at once.
Mine tends to get an annual outing.

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Old December 10th, 2007, 07:40 AM   #12
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Ron,


Here are the Tattle Tale monitors that our A/C shop purchased.

They bought them locally but I found this site that has a good picture of the device. Hope this helps

Gary
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Old December 10th, 2007, 10:20 AM   #13
Ron Beaufort
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thanks, Gary ... that's the one I remember - from about 30 years ago ...
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Old December 14th, 2007, 07:39 PM   #14
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So I found it...

model number 8878 'Digitective Annunciator'

You can hook 16 devices series or parallel or a combination of, it has a BCD display, it will display what circuit opened up first.

It is made by North American Mfg out of Ohio.

Not sure if it even works anymore... but its kind of neat

Someday I will let the magic smoke out of it.... i'm sure
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Old December 14th, 2007, 11:22 PM   #15
OkiePC
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Golden Nugget RSLogix tattle tale program Micrologix1000

Quote:
Originally Posted by [font=Arial
geniusintraining][/font]So I found it...




Me too...in the dark crevices of my gray matter...I found my best recollection of my Micrologix Tattle Tale.



This revived version is not as perfected as the original, IIRC.

It seems I have one too many rungs or branches. . .

As I recall the original could detect the drop out point of a circuit sealed in the beginning like this:



It would occasionally show two or more devices, including the button we pressed, but all in all, it was very useful for intermittent problems, and relay race chasing.

I remember wanting to measure or calculate the actual scan time but I never did.

Maybe someone can make it faster.

PiEaCe!
Paul
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