Mechanical delay.

[itsmoked]

Long ago I saw one of these but now that I could actually use one....nada

I want to prevent someone from starting a motor more often than every 15 minutes.(EVER!)

I have electronic timing so I can start a 15 minute timer that prevents hitting start again until it times out. But you get the clever/stupid operator who figures out that if power is lost the timer resets. Then they just crank off the disconnect and then back on, and away they go with a 30 second cycle.

I have seen mechanical bellows(?)types that essentially cock with the initial turn on then take x minutes, regardless of the power situation, to re-close.

Anyone have a lead, or know what these are called? Or have an effective alternate solution? Google bombed for me.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[ScottyUK]

Using 600V in a control circuit is a horrible practice, as is using 415V on our side of the pond. Usually a sign of cheap equipment made to a price, not to a standard. In the few instances where we have such equipment - and yes, it is cheap and nasty - we have specific warnings that line voltage is used in the control circuit.


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Sometimes I only open my mouth to swap feet...

 

[jraef]

No argument, but it happens nonetheless.

I have used line voltage on coils when there are very large contactors involved where the coil inrush would require a huge transformer to supply it. An interposing relay to a lower control voltage works wonders for that, and if there needs to be a timer involved, I have used the Agastats as that interposing device because its contacts were rated for it. I would never consider running a line voltage control circuit anywhere outside of a control panel though, in fact, not even off of the back pan!

 

[itsmoked]

Hi Opera. Yes I relize the need to 'charge" something. I thought it was interesting that most other brands only need 0.5-2 seconds and the, (otherwise), very nice RKE unit requires 7 seconds.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[waross]

Hi Keith;
We would love to know how the final design turns out.
Yours
Bill

 

[itsmoked]

Two cans, a spoon, an inner tube, a coat hanger, a rusty nail, and a baby's hand holding an apple.





I'll show you soon.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[waross]

I'm going nuts trying to reverse engineer that one.
LOL
Bill

 

[jraef]

..."and a baby's hand holding an apple."

Obscure reference to "White Punks on Dope" by The Tubes eh?

 

[itsmoked]

You caught that did you?

What do you want from life
To kidnap an heiress
or threaten her with a knife
What do you want from life
To get cable TV
and watch it every night

There you sit
a lump in your chair
Where do you sleep
and what do you wear
when you're sleeping

What do you want from life
An Indian guru
to show you the inner light
What do you want from life
a meaningless love affair
with a girl that you met tonight

How can you tell when you're doin' alright
Does your bank account swell
While you're dreaming at night
How do know when you're really in love
Do violins play when you're touching the one
That you're loving

What do you want from life
Someone to love
and somebody that you can trust
What do you want from life
To try and be happy
while you do the nasty things
you must

Well, you can't have that, but if you're an American citizen you are entitled to:
a heated kidney shaped pool,
a microwave oven--don't watch the food cook,
a Dyna-Gym--I'll personally demonstrate it in the privacy of your own home,
a kingsize Titanic unsinkable Molly Brown waterbed with polybendum,
a foolproof plan and an airtight alibi,
real simulated Indian jewelry,
a Gucci shoetree,
a year's supply of antibiotics,
a personally autographed picture of Randy Mantooth
and Bob Dylan's new unlisted phone number,
a beautifully restored 3rd Reich swizzle stick,
Rosemary's baby,
a dream date in kneepads with Paul Williams,
a new Matador,
a new mastadon,
a Maverick,
a Mustang,
a Montego,
a Merc Montclair,
a Mark IV,
a meteor,
a Mercedes,
an MG,
or a Malibu,
a Mort Moriarty,
a Maserati,
a Mac truck,
a Mazda,
a new Monza,
or a moped,
a Winnebago--Hell, a herd of Winnebago's we're giving 'em away,
or how about a McCulloch chainsaw,
a Las Vegas wedding,
a Mexican divorce,
a solid gold Kama Sutra coffee pot,
or a baby's arm holding an apple?

http://www.youtube.com/watch?v=00lccIIBA6s

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[itsmoked]

I'm baaaaaaaAAAAAaaack.

jraef....

I and an able associate spent much of yesterday trying to devise the required functionality with any reasonably available Agastat. We followed your,(broken - LOL), sentence about 20 times and come up with a similar but not desired functional result.

Here's the 7000 series Agastat data sheet.

http://relays.tycoelectronics.com/datasheets/7000.pdf

Let me reiterate hopefully, more clearly, the desired functionality.

Also the topology may not be exactly what was imagined.
The OUTPUT signal is the signal from a smart relay wanting to turn on and keep on the pump - not a push button directly controlling the pump. I need to protect the pump/SS from an insane "smart" relay.

Remember: The timer period is 15 minutes and must carry thru any power failure.

An OUTPUT, (from the smart relay), goes TRUE.
A timer starts AND an ENABLE signal to the SS goes TRUE.
The ENABLE signal stays TRUE until the OUTPUT goes FALSE.

IF the OUTPUT goes FALSE then TRUE before the timer times out. Then the ENABLE will never occur.

If the OUTPUT goes FALSE then TRUE anytime after the timer times out then the timer restarts AND the ENABLE occurs.

All I can muster from the Agastats is a time delay after the OUTPUT goes FALSE. This means the time period starts after the last time the machine is turned off. Which would mean an operator who runs the machine for 3 hours turns it off for a cancer-stick break returns 10 minutes later and can't start the machine for another 5 minutes. Not good.
(This would make sense if I was soft stopping the motor and needed to allow the SS to cool but I'm not.)



Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[ScottyUK]

Sounds like you want the 'delay at energise' or 'delay on' type plus a little bit of relay logic to get the enable signal. The type 7012 looks right from the timing diagram on page 1 of the link. You're describing the type 7032 'delay at de-energise' or 'delay off' behaviour.


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Sometimes I only open my mouth to swap feet...

 

[jraef]

D'oh, sorry.
I wasn't thinking of the "3 hours run time" scenario, so my more simplistic circuit will always have the restart delay as you have observed. "Not good" I take to mean not good eh?

OK, got one more unused output from the smart relay left? If so, I'll draft up the circuit and post it for ya. If not, back to the drawing board

 

[HCBFlash]

well dude, I guess I'll also chip in with a "how about" but not a ladder of the actual solution.

Use the 15 minute timer initiate when the full run condition is obtained. Use a 2p PB and relay if necessary to get this (instantaneous, non-maintained) signal. A N/C contact on the TOF will have permitted the start actuator (PB) to initiate the startup. After 15 min it will again permit start actuation. Yes, (X) minutes after any start actuation another will be permitted. Energizing the TOF after the "DRIVE START" signal has initiated the startup can be obtained as aux contacts/outputs from some "drives", or can produced by a CR or ordinary TDR.

I'd ladder this for you, but without familiarity with the actual SoftStart and fluid based TDR (TOF) chosen it'd be useless or worse yet, misleading.

Fluid based is not a necessity though. I've used TDRs with memory-like functions, whether battery, super cap, or whatever you'd like to call them. As far as that goes even lawn sprinkler timers are memory retentive these days.


...or am I entirely missing something here???

Please let us all know how this works out for you! and don't forget faq731-376

 

[itsmoked]

Thanks Flash!
You got me thinking along the lines of; make the Smart Relay do it.

I decided since I've blown my engineering budget on just this "simple" little SS/motor protection scheme, I'm going to allow the Smart Relay to "be" the protection.

Again, the problem is being able to carry thru during a power loss,(most likely intentional), the No-Restart-before-15-minutes-has-passed since the last restart.

Turns out the Smart Relay timers are all lost on PL but certain counter values are retained indefinitely.

I figure I can use this feature to achieve my mission,(already stated above), with only a small anomaly. I can count minute or second pulses constantly generated by a timer using a nonvolatile counter. The only caveat is if you turn off the power during this period the count stops and will pick up where it left off. So in a fifteen minute count if the yahoo turns off the power 10 minutes into the count and comes back three days later and turns it back on he will still have to pay the piper those last 5 minutes. At any rate this provides the 15 minute protection to the SS/motor which is the bottom line.

To wit; I have created this logic. It appears to actually work!! I'd like any creative criticism you guys might have.

I labeled most the non obvious stuff. Letters match the coils. Lower case seems to mean N.C. for some reason.
Oh and the "D" is a pulse, one Smart Relay cycle scan output pulse.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[itsmoked]

Just a little feed back.

Commissioned the Press today.
Couple of shots of the controller, and of the Press itself.
My controller is working great. There are a few details with the hydraulics that others will be fine tuning. None as bad as the hose that was missing so 1,100PSI hydraulic oil shot out the back hitting the wall twenty feet up. LOL

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[waross]

Hi Keith:
Sorry to be getting in late. Do you think that this would have worked?
1 A start signal pulls in the Agastat relay.
2 An instantaneous contact on the Agastat energizes a small relay that seals itself in and energizes the motor contactor.
3 An auxiliary contact on the starter de-energizes the Agastat.
4 The Agastat will now time for 15 minutes. A set of normally closed, timed contacts will now be open and are used to prevent a start signal from reaching the Agastat coil until 15 minutes has elapsed, regardless of whether there is power or not.
The small relay is for the purpose of avoiding circuit race. With some combinations of timers and contactors it may be dispensed with.
I hope that this is understandable.
Respectfully

 

[itsmoked]

Hi Bill.

That sounds like it would work!

I licked it with the above Smart Relay logic and its ability to remember a count thru power cycling. The Smart Relay was needed for other functions anyway.

It's in and running. (See above.)

Thanks.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[ScottyUK]

Dontcha just love all those exposed conductors? I' always wary when commissioning panels built in the US - too much needlessly high risk of inadvertent contact with something 'live'. I wonder why US manufacturers are so reluctant to follow the European practice of shrouding the majority of live parts on, for example, contactors and fuses? Puzzling!


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I don't have an attitude problem. You have a perception problem...

 

[itsmoked]

YeAAHH!

I hate that big disconnect! Just sitting there with death written all over it. Very annoying.

I was able to get a cover for the buss splitter but then it's nearly touchable without a cover due to its depth.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[jraef]

Scotty,
I comes from the ubiquitous influence of the Automotive industry on our standards and practices. They want everything easy to get at and test, no barriers or other "impedances" to getting the production line back up and running quickly. That is rapidly changing here though. They have begun stricter implementation of what we call Arc Flash Safety protocols which are now incorporated into our National Electric Code. Some of the things Kieth did might cause someone trouble later on if and when an inspector comes along and insists on an Arc Flash safety rating for that panel. As it is now, looks like a level 3, maybe 4. That would mean the full bunny suit if you open the box!

Keith,
I guess I'm going to have to come over and give you an education on Arc Flash safety construction considerations with regards to control panels. Just another excuse to have my boss pay for lunch eh?

 

[itsmoked]

Hey I'm up for that Jeff!

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com