water operated valve switch

Are you looking for a valve or flow switch. If a flow switch look to fire alarm equipment. A switch is made to detect flow in the water lines going to the sprinkler heads. If the sprinkler goes off flow in the line is detected by the switch. Switch sends signal to the fire alarm. Should work in your application.

You need two switches, one a pressure switch to tell you when the water is available from outside the house and a float switch to turn the motor off again when the tank is full.

Something like this:-

Have fun.

That is right. The one in the tank (float switch) is available with me but I don't how to get the other (pressure switch).

In the worst case, that could also be a float switch in the lower tank......switching on immediately there is enough water in there to pump to the upper tank....the only bad part is, you cannot then "suck on the mains" so to say......

What i neglected to mention before is that with low municipal pressure, you should install as large a bore pipe from the mains to the lower tank as you can get away with. Even if you cannot replace all of the pipe, replacing as much as you can will reduce friction and increase the flow.

http://www.water.siemens.com/en/Product_Lines/Control_Systems/Control_Systems_Products/Pages/cs_9G_float.aspx

http://wwwglobal.georgfischer.com/index.cfm?uuid=27E62E11D60EB5FC076AD78B18EA6DA4

To your list I would suggest adding WWW.grainger.com. They have over a dozen switches That could be used for this project.

We got water problems in our country such that we only get water for a few hours every other day. But the real problem is the water has no pressure to reach the higher floors. here is how we handle the situation. Every appartment has a tank on the ground level and a tank on the roof. When the water is running the lower tank is filled and is pumped from it to the higher tank. there is a float switch in every tank. the one in the lower tank will stop the pump if the lower tank is empty and the one in the roof tank will stop it when the roof tank is full. So we have a fully automated system. The reason for all this hustle is that the water supply is too small 1m3/h or less. So it is not possible to engage the pump directly to the supply.

Anyway if this is the case with you I suggest you follow this method rather than trying to find a method for detecting water in the supply pipe.

But I don't have a tank on the ground level.

OK Nosh I think i have a pretty idea of your problem. Andy has got the drawing for you. You don't need a pressure switch. The flow valve in the supply pipe will activate the pump when there is flow. And the float switch in the tank will stop it when the tank is full. the flow switch and the float switch are connected in series. The flow switch is normally open and the float switch normally closed.

In case the amperage of the pump is too much for the switches to handle you are gonna have to use a relay or a contactor to activate the pump.

That is you replace the pump in the dawing with the coil of the relay. And use the relay's normally open contact to activate the pump.

It might be a good idea to have one......as "sucking" on the mains, may give strange "happenings" with switches/flow meters etc etc.........

You could even suck air from a neighbour's system!!!! and he will get no water at all!!!

If the pipe that is connected to the municipality has a section of it that is lower than the connection. And the connection pipe can flow more water than the lift pump, then you will have created the lower tank that that Andy Germany described. If you install a water sensor in the low section of the connector, it will function in the same way as the flow switch. The advantage to a water sensor over a flow switch is increased reliability from lack of moving parts. In operation, whenever there is water flowing, it will collect in the low area of the pipe and cause the water sensor to turn on the water pump regardless of the amount of municipal water flow. If the flow is too small the sensor will no longer detect water and shut off the pump. If wired as Andy drew it you should have everything you desired. The only other thing you might want to consider is a delay timer that would not let the pump run till a few minutes after the pump last ran. This would help keep the pump from short cycling if the municipal water supply tends to trickle small amounts of water when not flowing normal amounts of water.

Good Post Bob.