Need help with 12v DC timer/wiring.

Thread Starter

TechJTB

Joined Jul 8, 2021
2
Good Morning, If I'm posting this in the wrong area please let me know and I can remove/move/delete as needed.

I'm not an electrician, I have some mild levels of electronic/wiring experience so I KNOW there is a solution to my problem, I just can't seem to find the correct part.
My issue: I have a large component that is outside from a location, powered by a breaker. This component has a new controller radio attached to it. We are now having intermittent issues with communication on said radio.

With the new design I believe when the power is on, the radio boots up faster than the component, then it doesn't recognize the component and we have a communication issue.
If I climb up there and power cycle the radio, bam, everything connects and plays nice until the next power blip, then we are back to no comms.

SO... what I'm attempting to do is add a 10-30 second delay on the power to the radio, the power is pulled DIRECTLY from a board on the component.
I have been playing with a NE555 12v timer. My setup was to connect the VCC and ground to the radio power, then a loop from VCC to the COM, then the timed closed out to the radio. This works but as soon as the radio gets power, it pulls all the 12v and the NE555 dies and the whole thing blips off, then tries over and over.

SO.... I'm needing to find a way to run both my timer AND my radio off the same 12v DC line with a simple solution.
I know one is out there it's just beyond my knowledge base, hence why I'm coming to the experts.
Any help is greatly appreciated!
 

MisterBill2

Joined Jan 23, 2018
18,176
SO the goal is to delay power application to the radio until after the "large component is fully awake. One interesting alternative would be to see if that "large component" has an "awake and ready" indicator, which would be perfect for switching on the radio power. Several oof my "toys" have indicators that do not illuminate until they are completely awake.
Depending on how much current the radio requires, it might also work to have an actual time delay relay do the switch for you. Then there would be no need for constructing an electronic timer circuit and housing for that circuit. If you used a 12volt time delay relay it could easily power from the same 12 volt source. And I know there are some timer devices in cars, Not the newer models, but from the time when there was not a computer running each feature.
 

Thread Starter

TechJTB

Joined Jul 8, 2021
2
SO the goal is to delay power application to the radio until after the "large component is fully awake. One interesting alternative would be to see if that "large component" has an "awake and ready" indicator, which would be perfect for switching on the radio power. Several oof my "toys" have indicators that do not illuminate until they are completely awake.
Depending on how much current the radio requires, it might also work to have an actual time delay relay do the switch for you. Then there would be no need for constructing an electronic timer circuit and housing for that circuit. If you used a 12volt time delay relay it could easily power from the same 12 volt source. And I know there are some timer devices in cars, Not the newer models, but from the time when there was not a computer running each feature.
Correct, that's what we are looking at now. Basically I have a 12v DC coming in and need to use that line and a relay or timer to give me a 10 (or longer) second delay before the radio powers on. Don't think we have many options with pulling signals from the device the radio is controlling. Will look into Relays.
Thanks for the reply and assistance!
 

Reloadron

Joined Jan 15, 2015
7,501
Sounds like what you want is commonly called a delay on make timer or relay. When power is applied to the load and the timer the timer will wait a preset period of time and close a relay which powers your communications schemes. A Google of "delay on make relay" should get you started and just make sure the relay can easily handle your radio load. While yes, you can build or roll your own simple off the shelf turn key solutions are plentiful, inexpensive and available.

Ron
 

MisterBill2

Joined Jan 23, 2018
18,176
another possible scheme would be to monitor the current drawn by the first device to see if it changes after the ting completes it's wake-up, boot up cycle. Current sensing might be a more effective way to provide the required delay. The beauty is that depending on if it changes and how much it changes the sensor could be as simple as a reed switch with a few turns of wire around it as a current triggered relay.
But measuring the current will require acces to the power supply wires.
 

Reloadron

Joined Jan 15, 2015
7,501
another possible scheme would be to monitor the current drawn by the first device to see if it changes after the ting completes it's wake-up, boot up cycle. Current sensing might be a more effective way to provide the required delay. The beauty is that depending on if it changes and how much it changes the sensor could be as simple as a reed switch with a few turns of wire around it as a current triggered relay.
But measuring the current will require acces to the power supply wires.
Yes, that scheme could also work. Personally I would go with a delay on make timer scheme but whatever works best for your application.

Ron
 

MisterBill2

Joined Jan 23, 2018
18,176
There may not be enough supply current change to make it work, but the idea is worth considering. All that we know is it is a "big device", and that is not very detailed.
 
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