Timer Question 1

[Waidesworld]

I have a need for a timer that can do the following,

We burn in components and sometimes need to pulse the burn in. The typical voltage is 12V and I can intercept the wiring between the power supply and the burn in board.

I'd like the ability to be able to pulse for a short period of time <1 min and also to allow it to run for a longer period of time <5 mins.

Is there something off the shelf that can do this for me, and where would I go looking for it.

Also, if I am in the wrong area (forum), that's more proof of how lost I am

drawn to design, designed to draw

 

[ScottyUK]

Have a look for the multifunction timers from the likes of Crouzet, Omron, SAIA-Burgess, Telemechanique to name a few.

Here's one of the UK catalogue pages to give you a start:

http://uk.rs-online.com/web/search/...4690&selectAttribute=Multifunction#breadCrumb

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If we learn from our mistakes I'm getting a great education!

 

[Waidesworld]

Scotty, thanks, now I know where to start looking on this side of the pond. I was close in my thinking but not exact.

 

[jraef]

What you need will be covered in what ScottyUK posted, but you have to differentiate between two types of functions:

1) Do you want it to repeat each burn in cycle once initiated and until you command it to stop? If so, that's called a "Repeat Cycle Timer" function.

2) If you want to initiate it and have it run once for the set time, then shut off until you initiate it again, that's called a 'One Shot Timer" function.

"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> faq731-376

 

[Waidesworld]

Jeff,

This would be a repeat cycle timer. I think at this stage I am going to call Omron/Newark and see what they recommend.

drawn to design, designed to draw

 

[catserveng]

I built a small test stand a few years ago to do a similar type job, I found using a "smart relay" worked better because it gave me a lot of flexibility. We used an AB PICO (a Siemens LOGO with a differnt label I think), and wer able to make it do multiple tests and support some different test requirements with fairly simple program changes instead of trying to find a different fucntion relay or do rewiring.

Hope that helps

 

[itsmoked]

I use these "smart relays" fairly often. They work quite well.

http://www.factorymation.com/s.nl/sc.2/category.22/.f

Check them out. You can download and mess with the software, writing your whole app and simulating it before you buy anything.

The nice thing about a smart relay approach is that you can read back some part of your test hardware, say, a microswitch, that detects when the part broke. You can have this detection stop the cycling and ring a bell or turn on a red light, etc..

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Waidesworld]

Keith,

I contacted factorymation this morning and the tech there was very helpful with my product selection. Now I wait for the UPS man to arrive.

drawn to design, designed to draw

 

[itsmoked]

Great!
You can start the programming while you wait.

Have fun.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Waidesworld]

OK I have a question that I am not finding an easy solution to. I bought the 24VDC powered version of the Teco (SG2-12HT-D) but the manual seems to suggest that I can only operate 24V with my Output and not the 12 I wanted.

I thought the unit was a 24V powered unit capable of turning on/off my power regardless of the voltages.

drawn to design, designed to draw

 

[itsmoked]

Try it. It could not work ?? but it shouldn't hurt it.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Waidesworld]

I checked and it had a "turn-on" at 15V so I can't use it. I have a 12V version on the way. I had originally asked for the tech support to suggest the best product based on all the knowledge I gave him and it ended up as the wrong part. I think there was a combined effort from both sides to get this one wrong, but at least I learned a lot more in the meantime.

drawn to design, designed to draw

 

[itsmoked]

OK. Was was actually surprised to hear about 12V. I thought they only made 24V. But when I confirmed that, I saw they did make 12V but that it's a different part number.

Let us know how you get on with the replacement.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Waidesworld]

OK got it all worked out and then went for the litmus test....bang..another issue. The unit was supposed to allow me to switch on five lamps on a burn in station. Problem is that the lamps consume 6.25Amps each and the unit I bought SG2-12HR-12D is only good for 8A output on the relay.
Is there another option for me?

drawn to design, designed to draw

 

[xnuke]

Use one relay output to provide power to the coils of five parallel interposing relays, each with 10 A contacts hooked to a separate power supply and your lamps.

xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[ScottyUK]

An appropriately sized motor contactor will switch whatever you want. Look for the AC-1 (resistive) current rating.


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If we learn from our mistakes I'm getting a great education!

 

[Waidesworld]

XNuke, can you elaborate on this. My Q out would hook to a bank of five relays on a separate circuit, turning it on and off as needed?

drawn to design, designed to draw

 

[itsmoked]

Ah yes.. Tungsten.

You will have large inrush on closing and some inductance on opening. The relays in smart relays do not like that at all.

So as XNuke suggests you need some interposing relays.

Back to the same place...

http://www.factorymation.com/s.nl;j...e3eSc3uNaNuTe34Pa38Ta38Pbhj0?sc=2&category=98

You'll want some relays with AT LEAST a 10A rating. I'd go for more. Like 15 or 20A personally. You will also want panel mounting sockets.

Think about a push to test button too. Some relays come with that feature. If it could be useful in your case go with that option. Sometimes in test setups that can be useful. "Is that lamp pointed/working correctly?"

How often are you cycling these relays? If you are running clickity, clickity, clickity, standard relays might also have issues.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Waidesworld]

I have ordered a part, should be here in a day or so and will let you know how it goes. We would only be tripping the relays about ten times a day tops. It's a six minute cycle with the relay but the lamps are being made and loaded which takes up to 45 minutes a load.

drawn to design, designed to draw

 

[itsmoked]

Mechanicals should be fine then.

Keith Cress
kcress -

http://www.flaminsystems.com