Hello AAC,
I am looking for some advice on how to problem solve the current issues with the circuit I designed.

Project
Create an timed automatic plant feeding system.

Objective
To fill and drain pots connected to a dummy pot. The water level to be controlled by float valves inside the dummy pot and feeding to be activated by a timer.

Mechanism
Timer switches on which activates the relay and sends power to pump A in tank which fills dummy pot with water until it reaches the level of the top valve which is NC. The water level rises until it opens the top valve which switches pump A off. Water stays in the pots until the timer switches off, cutting the power to the relay which cuts the power to pump A. The bottom valve which is NO is now closed due to water level, relay returns back to normal position and pump B which sits inside the dummy pot pumps the water back into the tank until the bottom valve becomes open and cuts the power to pump B. This cycle is repeated.

Issues
1) Relay buzzes / chatters
Relay is either flicking on and off or not flicking at all but an electric current can be seen jumping across the switch. Maybe the coil is received not enough voltage/current to keep the coil activated or it is receiving too much.

2) Both pumps stay on at the same time.
Circuit B which is constantly on due to the connection should not have any power when the relay switches to activate circuit A. Not sure why it is overpowering the relay. Maybe voltage is too high in live in or too low in live out.

Tried = Changing the brand of relay, Changing the voltage of relay. 240vac and 230vac as using power from mains. What did work was disconnecting the B circuit where the power stays on constantly and adding a second wire from connection 7 to connection 4 on they relay. This worked while circuit B is not connected but not when it is. Changed the wires, changed the pumps.

Any advice is helpful. The system does fill even though both pumps are on but would like to stop the relay from buzzing and have only one pump operational at a time. I have attached drawings to aid my description.

Component Specs
Power in cable = 250V 13A
Mechanical timer = 240V
Pumps = 220-240V 3A
Relay = 240V 15A & 230V 30A

 

The problem with AC relays in particular is they require the correct coil voltage once energized, if they are 'chattering' that is often an indication of low voltage occurring.
Max.

 

Don't this look better

 

Hard to tell but looks like he's toggling the relay coil with the relay buzz it like buzzer.

 

Don't this look better
View attachment 143984

Thank you

 

The problem with AC relays in particular is they require the correct coil voltage once energized, if they are 'chattering' that is often an indication of low voltage occurring.
Max.

So i need a way of maintaining the voltage once the coil has been energized?
Would a capacitor help?

 

Looks like you need to start over the way you have that is the switch at box A when closed powers the relay but as soon as it does it cuts the coil power.
Make the relay buzz like buzzer.
The way it looks your relay is not going to last long.

Need to post a link to your timer.

 

Terminal #7 on the relay coil needs to be connected to the Neutral .
Steve G

 

Looks like you need to start over the way you have that is the switch at box A when closed powers the relay but as soon as it does it cuts the coil power.
Make the relay buzz like buzzer.
The way it looks your relay is not going to last long.

Need to post a link to your timer.

Okay then. Do you mean create a complete new circuit. Here is the timer https://www.screwfix.com/p/lap-24-h...gclsrc=aw.ds&dclid=CP6vt4XH4tgCFeEC0wodi3gGuA

 

Terminal #7 on the relay coil needs to be connected to the Neutral .
Steve G

Okay will do that now. Thank you

 

Terminal #7 on the relay coil needs to be connected to the Neutral .
Steve G

View attachment 143986
still need see your timer tho

 

be80be please delete post #11. Post #8 has the corrected schematic
Steve G

 

https://www.screwfix.com/p/lap-24-h...gclsrc=aw.ds&dclid=CP6vt4XH4tgCFeEC0wodi3gGuA

Link to timer

 

Thank you guys will do this and then post results

 

be80be please delete post #11. Post #8 has the corrected schematic
Steve G

There the same yours just looks a little better LOL
There is no wiring link to the timer but you motor wiring doesn't look right.
need to see the timer

You have the motor running from neutral and L

Is not E and L the 240 volts

 

Believe E means ground. Same as in the USA except 240vac line voltage
Steve G

 

So i need a way of maintaining the voltage once the coil has been energized?
Would a capacitor help?

Relays are DC items, normally, because they require a constant potential drop across them to maintain a field in them so they will hold one position or another. Likely your chatter is because you're driving it with AC and it is flopping back and forth as fast as polarity is changing.

Either get a relay made for AC, or put a full-wave bridge rectifier in several places so the relay only sees DC through its inductor coil.

 

Believe E means ground. Same as in the USA except 240vac line voltage
Steve G

In the UK you would run a two wire and Earth, in N.A. it is two wire and Ground.
Max..

 

So it N and L and the E is ground
Here it's L1 and L2 N and ground

What been shown should fix it up then.

 

Relays are DC items, normally, because they require a constant potential drop across them to maintain a field in them so they will hold one position or another. Likely your chatter is because you're driving it with AC and it is flopping back and forth as fast as polarity is changing.

Either get a relay made for AC, or put a full-wave bridge rectifier in several places so the relay only sees DC through its inductor coil.

Thank you. I changed the DC relay to a AC stopped the chattering.