programmable digital timer relay suggestion

[Cameramonkey]

OK, fellow electronics geeks. I need a digital relay controller. My current obsolete system will go dark in December so I need to find a replacement. I'm going to switch from high tech computer controller (Unifi mFi) to a digital relay.

I need a programmable digital relay that can do the following with 12vdc:

Sense a switch changing state. (probably from closed to open)
Wait 5 minutes.
If still open at 5:01 close the relay. (to power up a buzzer)
If the switch closes, stop counting and wait until after the next trigger cycle.
When the switch closes, open the relay.

Suggestion?

 

[actaeon277]

https://www.amazon.com/gp/product/B07BT32T1M/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

You want something like this. Doesn't have to be this, just something like it.

Is this for an alarm to tell you your gate is open?
You can wire it different ways, depending on which timing option you use.

For instance, off the top of my head, voltage through the gate sensor goes to a NO relay. Opening the gate causes the relay to close, which powers the timer up.
If the gate closes while the timer is still going (less than 5 minutes) then power is removed from the timer. The timer always resets on power off.
If the gate stays open, the timer triggers an output.
(timer set up for "on delay")

 

[actaeon277]

?

 

[Cameramonkey]

Sorry, missed your response. I’ll look into it.

 

[actaeon277]

Is this about leaving your gate open?

 

[Cameramonkey]

No. That is no longer needed because the kids are 11 and 14 now.

This is for the extra downstairs fridge and freezer that gets left open and will stay that way all day because its not in a well traveled room. IF that freezer gets left open, LOTS of meat goes bad.

 

[actaeon277]

You know they have temperature alarms for fridges?

 

[actaeon277]

https://www.amazon.com/s?k=refriger...tor+alarm,aps,196&ref=nb_sb_ss_c_2_18_ts-ap-p

 

[Cameramonkey]

Wow. those werent there when I built this system.

 

[actaeon277]

downside, they don't tell you your door is open.

upside, it will tell you something's wrong, even if it's the compressor, which your door alarm wouldn't do.

 

[actaeon277]

Many different options. So study them first.
I think there were audible alarms, and alarms going to an app on the phone.
I saw those awhile ago, so I can't remember, I'm going off memory.

 

[Cameramonkey]

The benefit of the door sensor is I dont have to wait for temps to drop. I know in 2 minutes that the door is open.

it would be my luck that the sensor would get buried and I wouldnt know for hours

 

[maxwelhse]

If it were me, and I wanted to do something custom, I think I'd be looking into an Arduino and have access to all of the various fun sensors and stuff that comes with that world. They're not very expensive, but there is a learning curve. Then you can monitor door position, temp, amperage draw, etc, etc... All sorts of fun things.

May be habit forming...

https://www.amazon.com/ELEGOO-Project-Tutorial-Controller-Projects/dp/B01D8KOZF4

 

[jkaetz]

Put the thermometer in the front/top of the fridge or freezer, it will warm up quickly if the door is left open. I have a couple of the wireless sensors in our refrigerator and freezer and the will show a 5 degree jump in just a few minutes. You can usually set the alarm temp so just find out how much temp rise you get in five minutes.

 

[Cameramonkey]

The comment about my back yard gates jogged my memory. I have a spare ELK-960. One of its configs is a door prop alarm. I'll just wire one of those up to a bell. I had them for my gate to ring the single chime on my doorbell. (I needed a single-shot relay for my back gate and that is how I was using them)

Thanks guys!

 

[WebSnyper]

Are you doing anything with Zwave? If so, seems a simple door switch sensor would work and tie into existing hub (alarm system panel, or other smarthub)?