I have a time delay relay made by Hella and it was supposed to have a delay from 0 to 2.5 sec but on the zero setting it has 3/10th sec of delay. my question is would it be possible to rebuild this unit to get a delay time that is 0 to 1/10th of a second with an adjustment on it.? thanks for your help.
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Welcome to Electronics Point!
Please provide more details about what you are trying to do. What is the part number or model number of the Hella relay? Is it delay on release, or delay on actuation? Electromagnetic relays require a finite minimum time for the contacts to transfer, so three tenths of a second may be approaching that limit. You might want to consider a solid-state time delay relay. What load are you switching, what voltage, what current, is it resistive or inductive or capacitive? There is no such thing as "zero" delay: there is always a minimum delay from stimulus to response for any technology, although for some devices this delay can be just a few picoseconds. What are you trying to do?
It might be possible to "rebuild" your Hella relay by removing its contents and starting over from scratch, but I doubt there is any "simple" solution to make the original circuit "faster".
Please provide more details about what you are trying to do. What is the part number or model number of the Hella relay? Is it delay on release, or delay on actuation? Electromagnetic relays require a finite minimum time for the contacts to transfer, so three tenths of a second may be approaching that limit. You might want to consider a solid-state time delay relay. What load are you switching, what voltage, what current, is it resistive or inductive or capacitive? There is no such thing as "zero" delay: there is always a minimum delay from stimulus to response for any technology, although for some devices this delay can be just a few picoseconds. What are you trying to do?
It might be possible to "rebuild" your Hella relay by removing its contents and starting over from scratch, but I doubt there is any "simple" solution to make the original circuit "faster".
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Is it this one? If so, please note that, depending on how the two switches are set, the release time can extend to as long as 900 seconds. This is probably controlled by selecting the output of an internal counter for the longer intervals, with an adjustment to set the frequency applied to the internal counter. Note that the ranges do not overlap, implying there is some minimum frequency that is counted when the control is set to minimum delay. I doubt there is anything you can do with this device to reduce the minimum release interval, so perhaps you should consider a solid-state switch coupled with a 555 timer circuit.
Is SPDT operation required, or will SPST normally-open contacts suffice? Do you want the solenoid to operate immediately upon actuation of the relay, and then release after a time delay when the relay is deactuated? Omega Engineering (as well as other vendors) offers a large selection of solid-state relays for switching either DC or AC power (but not both in the same package... pick one or the other). They also offer industrial timers, but this is probably overkill for your application. A simple RC circuit that maintains the "ON" condition for a few milliseconds when commanded to "OFF" may work for you, depending on what kind of timing accuracy you need.
Is SPDT operation required, or will SPST normally-open contacts suffice? Do you want the solenoid to operate immediately upon actuation of the relay, and then release after a time delay when the relay is deactuated? Omega Engineering (as well as other vendors) offers a large selection of solid-state relays for switching either DC or AC power (but not both in the same package... pick one or the other). They also offer industrial timers, but this is probably overkill for your application. A simple RC circuit that maintains the "ON" condition for a few milliseconds when commanded to "OFF" may work for you, depending on what kind of timing accuracy you need.
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Well, please let us know what you find that may be useful. How do you intend to turn the solid-state relay "ON"? That could have an impact on how you delay the turn off. Also, does the solenoid really draw 10 amperes when energized? There are some solid-state relays available that are about the same size as the Hella product, but I am not aware of any that include a variable (or even a fixed) turn-off delay. How much delay do you need? Solenoids (and mechanical relay contacts) are relatively slow things. A ten millisecond delay on turn-off may not be significant, all depending on what you expect from the solenoid, performance-wise. I have seen some solenoids that are downright scary in how fast they operate. It all comes down to power over inertia.
I need to adjust the time of delay between 2/100s and 7/100s. I plan on powering the relay with 12v through a momentary button and when released the relay would count down and then send power to the solenoid. I wish that Hella were more accurate with there description of there product. If they had sais its 3/10s to 2.5 sec I wouldn't have waisted my money.
I think that you are expecting a bit much of a mechanical relay for the small time intervals that you require. As hevans said "Solenoids (and mechanical relay contacts) are relatively slow things".
My suggestion would be to build an electronic circuit with a timer(555?) and a Mosfet.
My suggestion would be to build an electronic circuit with a timer(555?) and a Mosfet.
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So... you push a button and nothing happens. Release the button and a variable amount of time later, adjustable from 20 milliseconds to 70 milliseconds, the solenoid is energized and remains energized. Did I get that right? How do you de-energize the solenoid? What is the HMI (human-machine interface) consequence of the delay after the button is released?
I can envision a "game" where you hold your hand under a guillotine and press a button. You now have twenty to seventy milliseconds to withdraw your hand before the really fast-operating solenoid drives the blade downward to sever your wrist. Other than that sick scenario, where do you need the response you are requesting? In other words, what are you trying to accomplish that requires such timing?
You haven't wasted your money if you learn something. Save that relay for another project.
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There are plenty of people here at Electronics Point that can help you if you want to build it yourself. If your solenoid operates from 12 VDC it would be simple to actuate it with a power MOSFET. OTOH, if you needed a relay to switch AC power to your solenoid, this is easily done with a TRIAC. The adjustable timing is an easy task for an NE555 timer integrated circuit. So, are you up to do a little electronics construction? Or are you looking for a turn-key solution that someone else builds for you?
I honestly don't know how that plays out here in the Forums... we are mostly here to give free advice, not to advertise for paid services. I am currently involved in a hands-on project that was started earlier this year by someone else, but I would be willing to help you after I finish it. Or someone else like @Kiwi might offer their assistance. All we ask is full disclosure and a little effort on your part.
As for Hella and their "deceptive" product description... you need to do "due diligence" before purchasing any component you have never used before to make sure it will perform as you expect. Interpreting datasheets is often very difficult, and sometimes the manufacturer leaves information out because they assume anyone "skilled in the art" will know about certain limitations... like the minimum switching time of relays. Building electronics is not like assembling a set of Lego blocks where everything is cut-and-dried and you just "follow the instructions". There is a huge range of options for every circuit and for every choice of component for that circuit. AFAIK Hella makes a quality product, just not what you needed or expected.
And you never answered my question: what are you trying to do?
I NEED TO BUY SOMETHING ALREADY PUT TOGETHER. iM NOT ELECTRIC COMPOTENT GUY. I THINK THE IF A COMPANY ADVERTISES THAT THERE PRODUCT DOES ACERTAIN THING THAT IT NOT TO MUCH TO ASK THAT THE PRODUCT DOES IT. THERES A HUGE DIFFERANCE BETWEEN ZERO AND 3/10S. THANKS AGAIN FOR YOUR INSIGHT. ILL LOOK AROUND AND FIND SOMEONE TO BUILD ME THE DEVICE I NEED. HOPEFULLY HE WONT USE ANY PARTS MADE BY HELLA.
HellasTechn
- Apr 14, 2013
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So you need a relay to click on 0 seconds ?
I have a few teledyne rf relays could theese be usefull for you ?
I have a few teledyne rf relays could theese be usefull for you ?
HellasTechn
- Apr 14, 2013
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Teledyne 412d to be specific.
Contact Bounce 1.5 msec max. according to datasheet
Check it out here.
http://www.teledynerelays.com/pdf/electromechanical/412.pdf
Contact Bounce 1.5 msec max. according to datasheet
Check it out here.
http://www.teledynerelays.com/pdf/electromechanical/412.pdf
I am going to press a momentary button that will send 12v to a relay then to a solenoid and when I release the button I need it to have a delayed response. That's why I thought a time release relay would work.The Hella unit I purchased would work if I could get the delay time down to the numbers that I need.
