Electronic relay Timer Question

[Chris64]

I hope this isn't in the wrong section - I couldn't find one more appropriate.

Anyway - My lube system on my Wells Index cnc was wired in a strange way when I got it (it would run momentarily each time you start the spindle). After investigating the problem during a rewire it seems they probably did this because the Trabon electronic timer was no longer working.

I've since been trying to find someone who makes an electronic timer/relay that I can wire into this, ideally cheap. No such luck. I'm not really sure how long this device would activate with each cycle but it could be adjusted from around 15 second - 2 hours. From what I saw on the internet it appears it may activate for around 10 seconds with each pulse.

I still have the solonoid and oil system, I just need a new trigger and I'd like it to be automatic still.

Any thoughts on this?

[One of Many]

That sounds normal. If the oil unit turns on then times out, it is functioning as expected. Then again, there are some that are intended as stand alone and have both on time and off time settings.

Many are wired to the spindle on time so they run periodically only when the spindle is running. Otherwise at idle they over/under oil if there is no parameter that controls the oil pulse interval via an output driven by the control itself. Some controls also have feedback input pressure switches to confirm lubrication and/or oil level in the resevior.

I'd investigate the system before deciding it needs changed. You could add a simple reset/cycle timer to restart the oiler every 1-4 hrs of spindle run time. Lots of simple options, but not sure it is warranted.

DC

[Chris64]

hmmm...ok that's good to hear that there was some method to the madness.

As far as investigating - well - that's not really an option as it's pretty much 100% gone.

to give a little background - this started as an early 80's wells index with an Allen Bradley/Dana/Bandit CNC. I've been inching along converting it to Mach3/Ghecko. I stole a lot of the guts from the old controller to re-use(transformers/relays/connectors/switches etc.) It's been fun but slow as I've just had other things going on and this is just a hobby machine. I have the 3 axis moving but I haven't wanted to start using it until I have the lube going.

I did notice that the current oil pump went into some "custom" circuit - one which I wouldn't want to re-use. This must've been added after the Trabon unit died.

Anyway - I like what you said about keeping it tied to the motor as this would certainly be equal to operating time. That will be very easy as I can just tie my power after the main connector L1 or L2 (3ph motor).

So, that said - I'm still stuck in a spot where I need a little device that can open and close a circuit on some form of programmable time. I'd prefer something with simple switches/dials so that if it's off for 3 months it won't forget it's programming.

It should be a simple solution - I just can't find one

[keebler303]

Crouzet has something which looks like it would work. You will have to find somewhere to buy it. Digikey stocks some of their parts but not this one. (www.digikey.com) You might be able to get it through them.

Check out function Li. I think thats what you are looking for.
http://www.crouzet-usa.com/catalog/s.../Chr2175mm.pdf

Matt

[One of Many]

Originally Posted by keebler303 Crouzet has something which looks like it would work. You will have to find somewhere to buy it. Digikey stocks some of their parts but not this one. (www.digikey.com) You might be able to get it through them. Check out function Li. I think thats what you are looking for. http://www.crouzet-usa.com/catalog/s.../Chr2175mm.pdf Matt

Hi Matt,

That might not be a bad selection. Just happens to be one on ebay for cheap

Digikey does have this style with independant on/off time also.
Omron Analog

Chris,

What was unclear, is that this lube pump came on for a while with the spindle. Which is to say there was some timing cycle functioning. Whether that was part of the pump or another timer, can influence how the new circuit timer is set up.

On a note of precaution. The above repeat cycle timers do not accumulate time, so on reset(spindle off) they do start the cycle over- pumping more oil at each spindle restart. To remedy this, another 1-2hr timer contacts could be placed across the repeat cycle/spindle contacts so it doesn't oil 30 times an hr, but continues the timing cycle at reasonable intervals at least once every 2-4hrs of run time. This is just one method, so there may be better options out there to reduce over oiling on short spindle cycles. Maybe Mach has a spare contact and lube cycle feature?

Just avoid too simple and cheap. There are synchronous motor timers that cam micro-switches that will accumulate time. The problem with these connected to turn on with the spindle is, it could take days to accumulate 4hrs run time in a hobby environment. Direct connected and they trigger at idle. Left on, they can drain a lube tank in a few days.

DC

[Chris64]

keebler - thanks for the link
one of many - thanks for locating one for me!

Those are good points you mention about the timer resetting with each start/stop...that might explain how my machine was dripping with it's current configuration - seemed like it was getting a little overlubed in my opinion. It would literally be sitting in a puddle.

I gotta do a little more research on that timer. May be just the ticket - and the price is good.

[One of Many]

Chris,

You may have considered this route too.

Logic Relay

This one is a 24vDC system, but they are avalaible in 120AC.

Grainger model SR2A101FU


These can reduce the wiring and number of components, but may not outlive simple timer relays. They can complicate things since they do not get programmed all that often. Loss of program could spell trouble. Then again going this elaborate, a well written program that incorporates lube confirmation prior to control enable is wise.

I've often thought about trying these units in some of our projects. Neat little package even at retail prices. Ebay prices are attractive, but still caveat emptor. I have had 25cent on the dollar purchases turn into 3x the headaches as a risk for being cheap.

DC

[Chris64]

The one on Ebay was also a 24vdc unit. i didn't want to have another transformer in there so I looked around a little more.

This one isn't nearly as nice - and hopefull works - but appears to be just the ticket. http://cgi.ebay.com/ws/eBayISAPI.dll...m=140292162645

So we'll see how the bidding goes, I've got my bid in though.

And I was thinking about this a little more - what I could do is power the timer off the main power switch so that it starts up when the machine is powered up. The difference would be that the power provided to the pump through the relay would be on the spindle power. I will need to have the timer frequency a little higher than a production shop would probably want, but it would keep it from oiling everytime the spindle starts.

[One of Many]

Chris,

Chances are you will be using a control voltage anyways with Mach. Possibly only 5volts, but normally that would be 24vdc in most industrial controls. Specific to the lube system, they are fairly isolated from the control, therefore not as critical to what voltage actually controls it.

That unit you have there works as an off delay repeat cycle timer first. Using the NO contacts, it delays once the power is turned on, then cycles your on time for the pump duration, then turn off again for the 600 seconds max off time= oiling every 10 minutes and repeat?

I don't think that is what you expected?

Data sheet

The previous repeat cycle timer Matt suggested was multi-voltage 24dc or 24-240AC. This one was also independantly setable from .6 seconds-100hrs on and off.

DC

[Chris64]

Originally Posted by One of Many Chris, Chances are you will be using a control voltage anyways with Mach. Possibly only 5volts, but normally that would be 24vdc in most industrial controls. Specific to the lube system, they are fairly isolated from the control, therefore not as critical to what voltage actually controls it. That unit you have there works as an off delay repeat cycle timer first. Using the NO contacts, it delays once the power is turned on, then cycles your on time for the pump duration, then turn off again for the 600 seconds max off time= oiling every 10 minutes and repeat? I don't think that is what you expected? Data sheet The previous repeat cycle timer Matt suggested was multi-voltage 24dc or 24-240AC. This one was also independantly setable from .6 seconds-100hrs on and off. DC

Thank you for that data sheet - that's great. I do think this will work still. I wasn't planning on triggering this from Mach. I wanted it to run on it's own. What was in place was a timer basically identical to this (except appearance). It ran from 120vac and sent 120vac to a solonoid that would trigger the oil injector thing (which also had a pneumatic input).

I'll admit that I'm not entirely familiar with how it works, but I'm sure that those are the units I'm interfacing with.

The problem that you brought up is valid of it reseting it's timer with each power cycle. I figure I can wire it up one of at least 4 ways that should all work with various pros and cons.
1) Cycles on main power switch regardless of spindle state.
2) Cycles on main power regardless of spindle state - but only sends power when spindle is running (What i think I'm going to try) *
3) Cycles on Spindle power - this may over lube if the spindle goes on and off a lot. This was the configuration and a problem with the previous set-up.
4) Cycles on Spindle power - but open is the starting state so that it would only lube after 5-10 minutes operating time or so. This way smaller jobs won't over lube it - but too many small jobs could underlube it.

* I may want to someday tie this into Mach so that it knows not to run while executing - I've heard this can cause the bed to actually float and cause tolerance probs.

[One of Many]

Tiz up to you, but unadvisable.

Yes, the table can float every 10 minutes using that timer in run time, regardless of how you hook it up. You will see it in the flat surface planes.

I'd be more inclined to hit a button evey few hours self latched to lube it as needed, than let that timer run on its own, w/wo spindle. But again that's your call.

The offering was free.



Best of luck!

DC

[Chris64]

Originally Posted by One of Many Tiz up to you, but unadvisable. Yes, the table can float every 10 minutes using that timer in run time, regardless of how you hook it up. You will see it in the flat surface planes. I'd be more inclined to hit a button evey few hours self latched to lube it as needed, than let that timer run on its own, w/wo spindle. But again that's your call. The offering was free. Best of luck! DC

yea - I'm still thinking about it of course - and I agree. A button that would trigger power the timer - which would feed itself power until the timer elapses, so a single quick press would hold for X seconds. That's certainly acceptable for a hobby setup and wouldn't be hard to change for a production environment.

hmmm...I'll play around with the rest of the parts I have and think about it a little more.

Thanks. I appreciate you callenging my ideas - it makes me think.