Field of the Invention
This invention relates to an automatic water level control system especially for sensing the level of water in an overhead tank and ground level water tank and for controlling the flow of water by automatically operating the pump set. This invention is particularly related to a float operated control system for sensing the level of water and thereby controlling the flow of water by automatically operating the pump set.
Background of the invention
Traditional way of controlling the level of water in the over head tank is by visually observing the level of water in the over head tank.
Upon detecting that the water level is low, turning on the pump set and allow water to flow to over head tank until desired water level is attained. When the desired water level is attained, the pump set is manually switched off for stopping water flow to the over head tank.
In order to control the upper level of the water in the over head tank a float valve is generally used i.e., to control inflow of water to the over head tank. Even then lower level of water to be manually observed and controlling of pump set has to be done manually. Electronically operated water level controllers which are available in the market utilize sensor probes which are prone for corrosion. In probe control switches chances for electric shock, loss of electricity through water, corrosion etc are more.
Generally float valves or ball type valves which are used in the known art, in the case where sufficient water inflow is there i.e. supply source are very high and there is no leakage in pipe lines. In this case float valves or ball type valves are used for controlling of input water. At the same time there no need of sub tank being supply is more and wherein the water is directly pumped to domestic water tanks. One problem generally faced while using above floats is the leakage of water because of the power pumping by the water supply authorities. The use of

float valve or ball valve is not enough to control the inflow water, because powerful pumping perishes the use of float valve or ball valve which resulting the water overflow from the tank.
Probes are using 12 volts DC supply and even some water controllers are using 230v supply to sense the levels. To check water level they are sending 12volt electric pulses in certain gaps of intervals.
It is an urgent need for an automatic water level control system to reduce the burden of manual observation of the water level in the over head tank and sub tank and thereby controlling the pump set manually. The present Invention intends to replace electronic probe by Floats which are free from corrosion and chances of electric shock and loss of electricity is nil compare with the electronic controllers and the present invention is provided to address all the drawbacks in the prevailing prior art devices as mentioned above.
Object of the Invention
It is one of the main objectives of the present invention to provide an automatic water level control system for sensing the level of water in an over head tank and for controlling the flow of water by automatically operating the pump set.
Another objective of the present invention is to provide an automatic water level control system for sensing the level of water in ground level water tank and for controlling the flow of water by automatically operating the pump set.
Still other object of the present invention to provide an automatic water level control system to enable the automation of house holds supply of water.
Yet another object of the present invention to provide an automatic water level control system for controlling the flow of water to a tank to keep the water level within pre determined limits.

Still another object of the present invention is to provide a float operated control system for controlling the level of water in the tank.
Another object of the invention is to provide a system where the power consumption is marginal.
Again other object of the invention is to provide a system wherein any voltage fluctuation will not affect the system.
It is one of the other major objectives of the present invention to provide a method for operating automatic water level control system for sensing the level of water in an over head tank and for controlling the flow of water by automatically operating the pump set.
Yet another object of the invention is to provide a system where the user can operate the water controller in case of emergency before automatic attention is attained.
Still other object of the invention is that to invent a system which is not required continuous voltage consumption and 24 hrs power supply is not required to for determining the water level.
Yet another object of the present invention is to provide a system wherein the pump set can be utilized to pump water from wells, ponds, river etc and while the water level goes beyond the float level, the pump will automatically switch off.
Another object of the invention is to provide a system wherein the water level in the sub tank also can be controlled for automatic operation of the pump set.
Summary of the Invention
The present invention relates to an automatic water level control system which automatically control pump set when the water attained a pre determined

level in the over head tank. When the water level in the over head tank exhausted to a predetermined lower level, and then the system is operated to switch 'on1 the pump set in order to pump the water to the over head tank. When the water level in the over head tank attained predetermined higher level, then the system is operated in order to switch 'off' the pump set in order to stop the pumping of the water to the over head tank.
In the present invention traditional handle type float is converted to string type and hindrances made in the string make possible the working of power switch and micro switches. Two ball type hindrances made on the string, these balls on the string pulling down or pushing up wards depending upon the level of water inside the tank.
The float movement is converted into 'on' and 'off1 function for automatically control the pump set. Float is designed such a way that it will goes up and down in the tank depends upon the water level. A spring can be used for facilitate up and down movement of the float. When water is exhausted the float will go down and when water pouring in to the tank the float will go upward. The float string is used to operate the switch. To supply current to the electric magnet two micro switches are used. Up and down movement of float's string causes to operate the micro switches also.
In the condition of enormous supply of input water one unit of automatic water level control system is enough to serve the purpose. For example when the water is pumping from wells, ponds etc. In case of shortage of input supply of water, two units of the system can be used. For example when the water is pumping from ground level tank to the over head tank, one unit of the said system is being placed with the ground level tank in order to determine the level of water in that tank and correspondingly operate the pump set. In this case the two units are serially connected and a novel wiring circuit also designed in order to suitably operate the pump set automatically depends upon level of the floats units attached with over head tank and ground level tank. Wiring started from main

supply switch to ground level tank then to top tank from there it is connected to the load.
This automatic water level control system is named as "ONOFLOT" automatic water controller. In the present system power consumption is marginal and any voltage fluctuation will not affect the system.
The method for controlling an automatic operation of a pump set by providing a water control system comprising: sensing the water level depending upon float levels connected with string; operating the micro switch by float weight and coil spring action; generating a signal to the control unit through the circuit which is connected with the micro switch; activating or deactivating the relay unit in the control unit depending upon the signal received from the float units for automatically operating the pump set.
Brief description of the drawings
1. Fig: 1 shows the positions of control unit and float units.
2. Fig: 2 shows the positions of micro switches, float, coil springs and switch plate in the float unit attached with the overhead tank.
3. Fig: 3 shows the positions of micro switches, float, coil springs and switch plate in the float unit attached with the sub tank.
4. Fig: 4 shows the complete wiring diagram (circuit) of control unit.
5. Fig: 5 shows the wiring diagram (circuit) of the float units in accordance with the present invention.
6. Fig: 6 shows the wiring diagram (circuit) of the water level control system operated from sub tank.
7. Fig: 7 shows the wiring diagram (circuit) of the water level control system while water pumping from pond, well or river.

8. Fig; 8 shows the wiring diagram (circuit) of the water level control system (Top tank only).
9. Fig: 9 shows wiring chart of dual control of water control system in accordance with the present invention.
10. Fig: 10 shows wiring chart of water control system in accordance with the
present invention (top tank only).
Detailed Description of the Invention
Fig: 1 illustrates a schematic view of the position of control unit and floats units in the over head tank and sub tank. In the present invention two float sets are used. One for over head tank (top tank) and the other one for sub tank (ground level tank). The float set used for over head tank is fitted on the top of the tank and two floats are put inside the tank. The two floats are named as 'ON float' and 'OFF float'. The floats are connected with nylon string. At the top tank 'ON float' is having long string and 'OFF float' is connected with short string. In the sub tank long string is used for "off float" and "on float "is fitted with short string.
Fig: 2 illustrate a schematic view of the position of the micro switches, float, coil springs and switch plate in the over head tank. In this figure micro switch attached with the 'OFF float' is placed over switch plate and micro switch attached with the 'ON float' is placed below the switch plate. The float movement is converted into 'on' and 'off' function for automatically control the pump set. Float is designed such a way that it will goes up and down in the tank depends upon the water level and a coil spring is used to facilitate up and down movement of the float.
When the water level in the over head tank goes down, ON float which is connected with the over head tank goes down along with the water level and thereby coil spring attached with this ON float also will goes down or it will be stretched down by the weight of ON float. So the switch plate attached with this

coil spring will also goes down and thereby push button attached with the micro switch will get pressed. This action (mechanical action) will activate the control unit and this activates relay unit and switch ON the pump set.
When the water level in the over head tank reached maximum level, OFF float attached with the short nylon string will goes up and thereby coil spring attached with the OFF float will also stretched upwards. The switch plate attached with the coil spring will also move upwards. So the micro switch attached with the OFF float will get pressed and circuit towards the relay will get automatically break and switch off the pump set.
Fig: 8 shows the wiring diagram of the top tank wherein the automatic water level control system is for top tank only.
Fig: 3 shows the position of micro switches float, coil springs and switch plate in the sub tank in accordance with the automatic water controller of the present invention. The water level in the sub tank (ground level) also can be sensed using ON float and OFF float. A separate unit should be attached with the sub tank. So wherever areas which require water level in the sub tank also to be checked and for controlling the operation of the pump set, one more float unit can be fixed. Only two differences between units attached with the over head tank and sub tank. In the over head tank whenever water expires, pump set will be get switch ON, but in the case of sub tank whenever water level in the maximum pump set will be get switch ON. Likewise whenever water level rises to the maximum in the over head tank motor get switched off and vice versa in case of sub tank (ground level tank).
The present invention comprises of two sets of floats which are connected with the nylon string for indicating level in both the tanks, plurality of micro switches, control unit, relay unit, power switch and switch plates where micro switches and coil springs are attached with. A combined and systematic working of float with string, micro switches, power switches, relay unit and control unit make possible automation of house hold supply. The control unit which is a main component of the automatic water level control system in accordance with the

present invention comprises of two poles, two contact relay, 16 Amps Toggle switch, press on switch, two LED bulbs and 12 volt, 500ma adaptor. In this one relay is used to activate the circuit connected to the pump set. Depending upon the sensing level signals received from the float units relay will activate or de¬activate the circuit to the pump set in order to automatically switch ON or switch OFF the pump set.
Fig: 4 shows the wiring diagram of the control unit. Further control unit comprises of 16 Amps toggle switch is option for automatic operation, manual operation and switch off option.
A push ON switch is provided in the control unit wherein a direct line from adaptor is connected to the relay ON through this switch. So whenever this switch got pressed 12 volt supply will be passed on and thereby pump set will be switched ON. In any urgent need user can operate this switch manually for filling up the over head tank, however pump set will be switched off automatically as soon as tank gets filled up. For instance, if user founds the sub level tank got filled up, he can operate this switch which is an additional manual mode operation is provided in the automatic water level control system in accordance with the present invention. The control unit further comprises of two LED bulbs for indicating power and to indicate the functioning of the pump set. The said control unit further includes 12 volt, 500mA Adaptor.
If the input water supply needs to be checked two controllers are to be used. These two controllers are internally connected by a novel circuit as indicated in Fig: 5. this fig shows the circuit connecting four micro switches for operating pump set. One additional float set have to be attached with the sub tank in order to check the water availability in the sub tank and if there is no water in the sub tank relay will not be activated and at the same time when water exhausted in the sub tank it will 'OFF' the relay. Additional option provided by the water level controller in accordance with the present invention is water level can be set. Whenever water level achieves a predetermined level the pump will automatically 'ON'.

In the condition of enormous supply of input water one unit of automatic water level control system is enough to serve the purpose (Refer Figure 8). For example when the water is pumping from wells, ponds etc. (refer fig 7)
Figure 9 shows complete wiring of incoming supplies and outgoing supplies for dual control. This compares top and sub tank control.
Figure 10 shows complete wiring of incoming and outgoing connections of top tank.
Working of the Invention
The present invention operates uses mainly mechanical components and it depends on floats and its weight. The present invention relates to a water level controller comprises of relay, float, micro switches and coil springs. Two float sets are used for sensing water level; one is for over head tank and other one for sub tank. If sufficient water in the sub tank, the two floats connected with the float set in the over head tank for indicating water level in the over head tank. In these situations micro switches allows positive continuity to the top float set. Whenever the top tank exhausted the "on float" is at the bottom of over head tank or whenever the predetermined reserve level achieved in the top tank, a positive supply touch with control unit. This contact activates relay and then contact open to the pump set. As soon as received the instruction from the control unit, pumping will be initiated and continuously pumping will be carried out in order to fill the over head tank. Whenever water filled in the over head tank or exhaustion of water in the sub tank makes break in neutral supply to the relay that causes to off the relay so supply to motor is broken.
In order to attain automatic pumping of water in the over head tank, a set of equipment is to be erected. One is at the top tank (over head tank) and the other is at ground level tank (sub tank). Sub tank water level is checked by another float set unit fixed on it. Generally in house hold supply two tanks are maintained, one is for storing the water (sub tank) and over head tank is for distribution of water.

In the condition of enormous supply of input water one unit of automatic water level control system is enough to serve the purpose. For example pumping from wells or from ponds, the input water supply is enormous.
In case of shortage of input supply of water two units of system can be used. For example when the water is pumping from sub tank (ground level tank) to the over head tank, one unit of the water level controller system is placed with the ground level tank in order to determine the level of water in the tank and correspondingly operate the pump set. The control unit placed in the over head tank and the control unit placed in the sub tank is internally connected by a novel circuit. As indicated, one float set is used to check the water available in the ground tank and if the level goes below the predetermined level, the controller placed with the sub level tank will break the supply to the relay it causes to break to supply current to the pump set. In the conditions like water exhausted in the sub tank or no water in the sub tank relay will not be activated. A predetermined level in the sub tank also can be set, so that whenever water reaches above the predetermined level, the said water level control will automatically 'on' the pump set.
Advantages of the Invention
1. Mechanical
The automatic water control system in accordance with present invention is working on mechanical techniques. It can be easily repaired and can be replaced because up and down movement is mechanically controlled. As described water level sensing and controlling of the pump set is carried out by floats and it is working as a mechanical device for 'on' or 'off' the pump set.
2. Float supported Control
In the present water control system floats are used to control incoming and outgoing water. It is also used for sensing the level of water in both the tanks. It is

one of main idea behind this invention to go for a mechanical control switch for avoiding more complicated costly devices.
3. Automatic water pumping mechanism from lower level tank
Each set of float units are provided in the upper tank and lower tank. The pump set can be operated from the tower level tank. Incase of water pumping by government agencies are restricted to some hours in daily or some days in a week, the pump set can be operated from the lower level tank with this invention such that pumping of water will be started automatically when a desired level of water is reached in the lower level tank. In general wherever water pumping is not regular from water supply agencies to obtain maximum water, a float set (ONfloat) can be placed at brim of lower level tank and as soon as water get filled up in lower level tank the pumping can be started automatically and after water got filled up in a predetermined level or desired level pump set can be automatically switched off. At over head tank also a float set (OFFfloat) is provided in order to prevent over flow.
4. Low production cost
Automatic water level control system is developed using low cost available materials in the market and it is manufactured in a simple manner, hence production cost is least compare with the other water level controllers available in the market.
5. Easy to fit
It can be fit easily at the top of the tank and no other additional fittings are necessary. It can be simply fitted at the top of tank and float can be provided inside the tank on the water and it can be connected with load.
6. Easy to repair
Simple mechanical components are used in this invention. So it can be easily repair or replaced without much effort.

7. Agricultural use
An agriculturist can operate this automatic water level controlling system for pumping water from ponds or well or even from a river. For this purpose float unit can be fitted at the top of the input source and "off float "in a position just top of foot valve. So whenever water goes below this level the pump set will automatically switched off and system will wait to attain to the desired level to start further pumping, so whenever water comes in ponds pump set will automatically operate and irrigation can be done accordingly.
8. Precise working
Working of this invention is based on the factors such as weight of the float and strength of spring. So working of the said system will be precise and accurate and therefore maintenance cost will be very less. The life span of the said system will be more than other systems available in the market.
9. Relay contacts
Control unit is incorporated with 2 pole 2 contact relay and it is generally agreed that connecting through relay is perfect contact available in electric connections. With precise circuit it automatically 'off' without power supply and this gives long life to the relay and no extra electric charge to the customer.
10. Suitable for any pump set and any tank
This system is suitable for any pump set or any tank. This system can be able to operate with high powered motor however pump set which is having capacity more than 1hp; it has to connect through starter coils.
11. Prevention of water loss
A very important factor of this invention is to prevent loss of drinking water. In India drinking water is precious because there is not adequate arrangement. The availability of the purified water is limited. Even in cities, the government

agencies were not able to supply adequate quantity of water. In this juncture wastage of drinking water is serious national loss. The present water controller is absolutely preventing wastage of water which flowed from the over head tank while pumping is going on after the tank is filled.
Features of automatic water control system
1. Float controlled system which utilizes float as a sensing device and thereby electronically operated sensing is avoided.
2. Coil spring is used in the float unit and float weight is used to operate micro switches.
3. Constant consumption of electricity is not required so that amount of energy benefited to the society in the period of power cuts.
4. The pump will start pumping when the lower level tank is attained a predetermined level of water and this system can be used in wells, ponds even river also.
5. The system is operated using relay (2 poles 2 contact relay) and can be controlled from sub tank, (refer Fig 6 )
6. The novel wiring circuit which starts from lower level tank to upper head tank and the said water controller comprises of 'ON float' which is for 'on' the pump and 'OFF float' which is for 'off' the pump under one float unit.
7. Quantity of water is more where a normal water controller can fill at most four feet of water. But in this invention, this controller can fill 20 feet of water at one time
8. It can use well, pond or river as input source of water and can also put floats in it when water goes below the fixed float level the pump will automatically 'off'

9. It can operate from sub tank also. In city areas water supply is restricted to some days or some hours. In this cases input water is important so we preserve the input water whenever we getting it. The system automatically 'on' when the down tank is full. At the same time it 'off' the switch up to overflow' see sheet 6, fig 6 it is very useful for pumping waste water, rain water.

I Claim:
1. An automatic water level control system comprising:
plurality of float units connected with string for sensing the level of water;
coil strings which are interconnected with the said float units;
plurality of micro switches placed with the switch plates, having push buttons attached with it.
a control unit which comprises of a relay which activates and deactivates the pump set depending upon the water level sensed from the said float unit.
a circuit interconnecting plurality of micro switches, control unit and pump set.
wherein the float movement is sensed to determine the level of water and thereby activates or deactivates the relay through micro switch for automatically controlling the pump set and the float weight and coil spring action are used to operate the said micro switches.
2. The automatic water level control system as claimed in claiml, wherein the controller comprises of four micro switches and two float units with strings and for sensing the water level.
3. The automatic water level control system as claimed in claiml, wherein the control unit further comprises a toggle switch, a press-on_switch for emergency pumping with suitable arrangement, an adaptor and two LED bulbs.
4. The automatic water level control system as claimed in claiml, wherein the relay is a two pole two contact relay.
5. The automatic water level control system as claimed in claiml, wherein the string is a nylon string.

6. The automatic water level control system as claimed in claim1, wherein the float unit comprises of two floats in which 'ON float' is used to 'ON' the pump set and 'OFF float' is used to 'OFF' the pump set.
7. The automatic water level control system as claimed in claiml, wherein the circuit interconnects the control system units in both sub tank and over head tank.
8. The automatic water level control system as claimed in claim 1 to 7, wherein ON float is connected with longer string and OFF float is connected with shorter string in overhead tank and vice versa in sub tank.
9. The method for controlling an automatic operation of a pump set by providing a water controller as claimed in claims 1 to 8 comprising:
sensing the water level depending upon float levels connected with string;
operating the micro switch by float weight and coil spring action;
generating a signal to the control unit through the circuit which is connected with the micro switch;
activating or deactivating the relay unit in the control unit depending upon the signal received from the float units for automatically operating the pump set.
10. The automatic water level control system as claimed in any of the preceding
claims can be operated in manual mode also.