Stop my house flooding

[Sintra]

Ok here is the scenario.

My house is built over an underground stream and has a manhole in the middle of the utility room. Last autumn the water rose up to the level of the manhole nearly flooding the house so I need you guys to come up with something to prevent this.

I have installed 2 float switches and a pump within the manhole but I haven't got a clue how to wire it. The float switches are volt free contacts and when in the horizontal position they are open circuit and when in the raised position closed circuit. The pump is a 230V submersible pump and is suitable for the environment. On the diagram I have drawn there are 3 water levels normal and 2 high level positions. What I need to happen is as follows. When the water level reaches high level 1 from normal level the lower float switch will rise and close the contacts but at this stage I do not want the pump to run. When the water level increases from high level 1 to high level 2 the upper float switch will rise and close the contacts. At this point I want the pump to run. The pump should now run until the water level drops below the lower float switch and opens its contacts thus turning off the pump. To complete this circuit you might need to consider additional components to get this to operate correctly.

 

[trev]

I'd do away with high level 2 and have the pump on a 3 plate system with high level 1 being the switch that kicks the pump in. Can I have a prize

 

[Sintra]

I'd do away with high level 2 and have the pump on a 3 plate system with high level 1 being the switch that kicks the pump in. Can I have a prize

Sorry Trev but I'm all out of prizes

 

[trev]

.....Got to admit though frank, It's a canny idea

 

[Happy Jack]

Here is my attempt. Probably the last time I'll have a chance to sit down and look at these for a short while, but I'll try sit down next week at some stage and explain my reasoning.

I'm not overly familiar with the term 'voltage free'. It strikes me as something of a misnomer, but rather than Google it could anyone explain what that means in simple terms?

And would a flyback diode in parallel with the 12V-R1 relay coil be a good idea?

 

[Sintra]

Hi mate and thanks for trying to save my house lol. Volt free means just that the contacts don't have any voltage apart from what you apply to them. I have had a quick look at your drawing but not sure it will work as intended will need to check it out when I'm on the PC as its a bit small on the phone.

 

[Happy Jack]

Volt free means just that the contacts don't have any voltage apart from what you apply to them.

I feel a bit silly now. Thanks for clarifying that.

I have had a quick look at your drawing but not sure it will work as intended will need to check it out when I'm on the PC as its a bit small on the phone.

I'd appreciate that, and understand the inclusion of the TX and bridge arrangement to derive the 12Vdc wasn't really necessary. Thought it might be nice to guild the lily, so to speak, as I had a bit of time this evening. Thanks again Sintra, these little exercises are good practice.

 

[Marvo]

Here is my attempt. Probably the last time I'll have a chance to sit down and look at these for a short while, but I'll try sit down next week at some stage and explain my reasoning.

I'm not overly familiar with the term 'voltage free'. It strikes me as something of a misnomer, but rather than Google it could anyone explain what that means in simple terms?

And would a flyback diode in parallel with the 12V-R1 relay coil be a good idea?

View attachment 18338

I have to be honest and say that's a very valiant attempt, I particularly like the transformer with the fused secondary and the rectifier / smoothing cap circuit. The self hold (latch) circuit on the left hand relay tied back to float switch 2 NO contact almost gave me wood

Being naturally bone idle lazy I would have taken the float switches as being 230v.

 

[Floody]

What software do people use to draw their circuits on?

 

[Marvo]

I usually use Micros0ft Visio just because it's 'shapes based' which means it's the quickest. If you're looking for something to use you could try Sketch-up which is free. It can be used to make wireframe type drawings but you'd need to use your print screen button to save as a jpg.

 

[Sintra]

I feel a bit silly now. Thanks for clarifying that.


I'd appreciate that, and understand the inclusion of the TX and bridge arrangement to derive the 12Vdc wasn't really necessary. Thought it might be nice to guild the lily, so to speak, as I had a bit of time this evening. Thanks again Sintra, these little exercises are good practice.

Well that circuit that you have come up with is spot on although I am as lazy as Marvo and would have kept it all at 230V also :lol: It's good to see a bit of thinking outside the box.

 

[Sintra]

Now that the circuit is up and running I think I would like to add a little 3 light annunciator so as I can see what the water levels are like without having to open the man hole. It will have 3 lights and the only lamps I can get for it are 230V the green lamp will be lit when the water level is below both float switches (normal) the amber lit when the lower float switch is operated (level 1) and the red lit when float switch 2 is operated (level 2).

 

[Happy Jack]

Being naturally bone idle lazy I would have taken the float switches as being 230v.

I have been known to overwork problems in the past. The idea of 12vDC SELV appealed to me given the proximity to water.

What software do people use to draw their circuits on?

I use a combination of Google Sketchup 8 for 3D modelling and Autodesk Autocad 2010 for 2D / line drawings and schematics. Sketchup is an excellent introduction into CAD.

Now that the circuit is up and running I think I would like to add a little 3 light annunciator so as I can see what the water levels are like without having to open the man hole.

I might sit back on this one, Sintra. I anticipated some form of warning system, so have a circuit in mind that, on first glance, appears to function as intended.

 

[Happy Jack]

I anticipated some form of warning system, so have a circuit in mind that, on first glance, appears to function as intended.

It appears I stand corrected. Owing to the self-holding nature of 12V-R1, the annunciator functions as intended prior to the pump running as the water level rises, but not as the FLSW-L2 disengages at step 4 and the water level falls.

I think I might be missing a trick, here, so any comments would be welcome. Although if I'm perfectly honest, I do prefer it this way. But then I would say that.

Let me explain by way of a few drawings.

Step 1 -


Step 2 -


Step 3 -


Step 4 -


Step 5 -

 

[Sintra]

Brilliant effort mate I like it. The only problem is as you say in step 4 where the water level has fallen below the top float switch. I really think I would like to see that amber light coming on at this stage so as I can reassure myself that the pump is doing its job lol. TBH mate I haven't tried working out how to do it myself as I'm doing long hours this week but the first chance I get I will be onto it.