Solid State 110 Volt timer delay circuit help II

Thread Starter

iONic

Joined Nov 16, 2007
1,662
In reference to the closed post...

MalcomV8 said:
Hi Guys,

I've been trying to build a simple power up delay circuit for 110 volt skimmer/pump on my salt water fish tank. My issue is that in a power failure water levels change. The sump water level rises a few inches. When power comes back on my auto top off pump is confused and pumps extra water in and my skimmer kicks on with the wrong water level and dumps nasty collected crud back into the tank.

However if both of those items could be on their own delayed power up it would cure those issues. So when power returned if there was a 3 ~ 5 minute delay for the water levels to stabilize and go back to normal, then my skimmer and auto top off get powered back on they'd work as expected.

Thanks for any pointers or advice.

Malcolm
I think we can help this OP out, but with a much different circuit design using mains isolation or perhaps some over the counter solution. Shutting him down this fast seems a bit unfair when we could have just removed his "illegal" schematic.
 

MalcolmV8

Joined Aug 31, 2011
7
I'm not even sure how my schematic was illegal? I mean it wasn't even mine, just a link from a "how to" electronics circuit website. It was not designed to harm people or anything like that.
 

MalcolmV8

Joined Aug 31, 2011
7
Oh. But in this case that's the idea. It's just a delay to a 110 volt device. I'm not trying to power a 12 volt device etc. without a transformer. I need a delay to my skimmer which is 110 volts.
Doesn't seem to make sense to use a transformer to drop to 12 volts, create delay and then use step up transformer to get back to 110 on the other side.
 

praondevou

Joined Jul 9, 2011
2,942
Oh. But in this case that's the idea. It's just a delay to a 110 volt device. I'm not trying to power a 12 volt device etc. without a transformer. I need a delay to my skimmer which is 110 volts.
Doesn't seem to make sense to use a transformer to drop to 12 volts, create delay and then use step up transformer to get back to 110 on the other side.
You're right, doesn't make sense. But you will not be able to discuss DIY non-mains-isolated circuitry here on this forum. You could buy an off the shelf ON-delay relay.
 

Thread Starter

iONic

Joined Nov 16, 2007
1,662
MalcomV8,

Think along these lines. The delay you use must be able to plug into the wall and have a transformer to isolate the mains supply. What about modifying a power strip to include a power failure/return circuit to trigger the delays(via DC circuit & voltage) the 120V relays for the devices you need to sequence on.

From reading your first post you suggest that if when the power returns, all you need is for nothing to happen for 3 min. to 5 min. Then my skimmer and auto top off get powered back on they'd work as expected.

So inside the power strip you can add a small 9V or 12V DC switching supply. Returning or applying power to the switching supply will automatically start a timer. When the timer runs out a relay is switched on, supplying power to the remaining outlets on the power strip. The relay will trigger with 9V - 12V and be able to supply 120V mains power to the devices.


Here is a 5minute timer that sets off an alarm, but can be easily modified to trip a relay for mains power.



Does this sound as though it is doable from your end?
 
Last edited:

MalcolmV8

Joined Aug 31, 2011
7
You're right, doesn't make sense. But you will not be able to discuss DIY non-mains-isolated circuitry here on this forum. You could buy an off the shelf ON-delay relay.
That makes sense. I had searched for off the shelf solutions first but I think the key was knowing exactly what to put in a search engine. After your post I found "on-delay relay" returns a lot of hits and something like this would actually do exactly what I want for the skimmer only (more on this in a sec).

http://www.gsistore.com/ic0secdeonma.html

It's only 1.5 amps but I think that's more than enough (will go double check) and it's only $5.45 which is not bad.

MalcomV8,

Think along these lines. The delay you use must be able to plug into the wall and have a transformer to isolate the mains supply. What about modifying a power strip to include a power failure/return circuit to trigger the delays(via DC circuit & voltage) the 120V relays for the devices you need to sequence on.

From reading your first post you suggest that if when the power returns, all you need is for nothing to happen for 3 min. to 5 min. Then my skimmer and auto top off get powered back on they'd work as expected.

So inside the power strip you can add a small 9V or 12V DC switching supply. Returning or applying power to the switching supply will automatically start a timer. When the timer runs out a relay is switched on, supplying power to the remaining outlets on the power strip. The relay will trigger with 9V - 12V and be able to supply 120V mains power to the devices.


Here is a 5minute timer that sets off an alarm, but can be easily modified to trip a relay for mains power.



Does this sound as though it is doable from your end?

That does sound like a possible solution. The power strip idea. I'll explain what I had envisioned.
I envision what looks like a mini extension cord about 1 foot in length and in the center of the cord is a little black box causing a delay. This works for the skimmer.

This way an already established tank setup such as mine (and I have a lot of them) just finds the skimmer plugged into power outlet, unplugs it, plugs in the delay "dongle" and plugs the skimmer in the other end of it.
You are absolutely correct in that it's only function is that when power fails do not allow power to return immediately to the skimmer. Wait approx 3 to 5 minutes.

For my auto top off I envision a similar item except the box has three cords coming out of it. One that plugs into a power strip to check if power has failed. The other plugs into the output of the auto top off (a 110 outlet). The third is the female end that the top off pump plugs into.

The reason for the slightly different design is when the auto top off controller decides to send power to the top off pump it can't have any delay in normal circumstances. In fact the auto top off controller will only send power for X seconds (20 in my case) and then shut off for X period (12 hours in my case). That's safety so that if the top float that triggers water level is high enough fails I won't have a flood in the living room. So there needs to be a third connection monitoring a/c power and knowing that power has been available for the past 3 ~ 5 minutes and that we have not just returned from a power failure and this is a false trigger for more water.

OK now that you see what I have envisioned and what I'm trying to accomplish you can probably see why I was looking at the circuit I was looking at. Especially if I have to build a lot of them. I have quite a few tanks myself and I have lots of friends with tanks that would love this too.

So I chose the triac method to keep away from relay costs and also their simplicity. Of course you guys can't discuss said circuit with me on here.

I have to say warning people that certain circuits are dangerous when not handled correctly or encased inside a sealed plastic case in a block of resin is one thing but then just flat out banning people from even talking about them is ridiculous. I'm going to assume this forum is hosted in a repressive country? Just asking.
 

Thread Starter

iONic

Joined Nov 16, 2007
1,662
Now your starting to confuse me. My assumption was that once 3min to 5 min had passed you could turn on both devices at the same time and everything would be OK. Now it seems that you need to delay some amount of time after the skimmer is on before turning the top-off pump as well. In the scenario I described you would then need 2 555 circuits and two relays wired to different outlets on the power strip.

ICM102 Documentation
 

MalcolmV8

Joined Aug 31, 2011
7
Sorry I don't mean to sound confusing. Skimmer and top off pump can both resume normal operations after 3 ~ 5 minutes.

The skimmer is super easy. Just unplug it and delay it's power.

The top off is not so easy because it's not a stand alone unit. Let me post a pic



OK see that black looking power strip? That's called a Reef Keeper and is an electronic power strip that's programmable. The orange cable you see coming off of it runs to the basement and powers the top off pump when it needs more water.

However I can't just delay power to the RK (reef keeper) as it controls many other things, halides, cooling fans, heaters etc. So all I need to do is intercept the orange cable immediately after a power outage.

However the orange cable is not always on like the skimmer so the exact same design wouldn't work. The orange cable only powers on momentarily when it's doing a top up.

Does that make sense? That's why the "module" that interrupts power on the orange cable would have to monitor a regular outlet on a regular power strip to see if power has failed or not.
 

Thread Starter

iONic

Joined Nov 16, 2007
1,662
So the reef keeper decides when the top-off pump turns on. Does the reef keeper have a battery backup so that it's timing is kept accurate? And the Top-off Pump needs to know when the power is out/back on so that after 5 min it will turn on for xtime and then resume normal operation as it's set time?

What if the Top-off pump was plugged into the 5min timer box so that it would turn on after a power failure, and also ran from the timer box to the reef timer, plugged in as you see. Then It would function as you need it to, both on scheduled times and after a power failure/resume event.

OOPS! Thant wouldn't work, the pump would be on always. The first timer in the power strip I suggested would need to trigger a second timer, and relay for the pumps normal time then turn off so that the reef keeper takes over.
 
Last edited:

mcgyvr

Joined Oct 15, 2009
5,394
Malcom,
How is it that your autotop off confused? When the water level rises the floats should NOT allow the autotop off to come on at all when power comes back on. The auto top off should ONLY turn on when the floats fall below normal water level..not above it

I have a similar reef setup with sump/skimmer/autotop off and do NOT have this problem at all.

Also sounds like your skimmer pump is either over-sized for your setup or return pump under-sized. The water level should only rise a few inches in a power fail situation and my return pump has lowered the water much faster than the skimmer takes to fill up and go crazy letting out the stinky skimate. Never a bad idea too to add an overflow tube dumping into a milk bottle or whatever for your skimmer too incase you forget to clean the cup or this situation happens. The extra water/skimate would simply drain into the milk bottle instead of back into the tank
 

MalcolmV8

Joined Aug 31, 2011
7
Malcom,
How is it that your autotop off confused? When the water level rises the floats should NOT allow the autotop off to come on at all when power comes back on. The auto top off should ONLY turn on when the floats fall below normal water level..not above it
That part is correct. However when power returns and the return pump kicks back on it pumps water back to the tank and the water level drops below the floats for about 30 seconds while you wait for the water to pump up in the main display tank and to drain back. It's approx 30 seconds give or take where the sump level is out of wack and will return to normal height. It's in this time when it drops that the auto top off kicks on pumping in unwanted water.

Also sounds like your skimmer pump is either over-sized for your setup or return pump under-sized. The water level should only rise a few inches in a power fail situation and my return pump has lowered the water much faster than the skimmer takes to fill up and go crazy letting out the stinky skimate.
My sump is narrow and tall. That's why I get a lot of height change on power failures. I was unable to use a wider sump because it's all squeezed under the tank stand in the living room for a clean look. Had I used a wider sump with a lot more water volume it would probably remove both of my issues.

Never a bad idea too to add an overflow tube dumping into a milk bottle or whatever for your skimmer too incase you forget to clean the cup or this situation happens. The extra water/skimate would simply drain into the milk bottle instead of back into the tank
I'm working on something similar. I actually have access to a drain and may put the skimmer over flow directly into it but we'll see.
 

mcgyvr

Joined Oct 15, 2009
5,394
That part is correct. However when power returns and the return pump kicks back on it pumps water back to the tank and the water level drops below the floats for about 30 seconds while you wait for the water to pump up in the main display tank and to drain back. It's approx 30 seconds give or take where the sump level is out of wack and will return to normal height. It's in this time when it drops that the auto top off kicks on pumping in unwanted water.
Can you change the height of either your return pipe anti siphon holes (in the display tank) or your overflow lip? If they are closer as soon as you start pumping water again it will start to drain back down at the same time preventing the height issue. I'm all about simple mechanical fixes first as they are typically less prone to failure than electronics.
 

MalcolmV8

Joined Aug 31, 2011
7
Can you change the height of either your return pipe anti siphon holes (in the display tank) or your overflow lip? If they are closer as soon as you start pumping water again it will start to drain back down at the same time preventing the height issue. I'm all about simple mechanical fixes first as they are typically less prone to failure than electronics.
Those are already as close to tolerance as they can get. Like I said this sump is to small and skinny for the display tank but it's the largest that would fit completely enclosed under the tank stand out of sight. It was chosen for esthetics because it's in the living room all self contained. No fish room or large sump behind or along side the tank etc.
 
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