19-10-2012, 02:05 PM
Water Level Indicator
Water Level.rtf (Size: 5.21 KB / Downloads: 133)
INTRODUCTION
If you need a fully automatic water level controller circuit then try this circuit Water level controller. The circuit is fully based primarily on transistors. The sensing section is somewhat similar to this circuit but there is additional circuitry for switching the pump ON when the water level falls below a set level and the pump will be switched OFF when the tank is full. Few transistors , one 555IC and an electromagnetic relay is used for realizing the control section. The circuit is very simple cost effective , reliable and many guys have successfully assembled it.I am also working on a float type water level indicator/controller using the float type fuel gauge mechanism used in motor cycles.The level sensor section is finished and now I am working on the control circuitry. I will add the circuit here as soon as it is finished.Here is a simple, versatile cir- cuit which indicates the level of water in atank. This circuit produces alarm when water level is below the lowest levelL1 and also when water just touches the highest level L12. The circuit isdesigned to display 12 different levels. However, these display levels can beincreased or decreased depending upon the level resolution required. Thiscan be done by increasing or decreasing the number of level detector metalstrips (L1 to L12) and their associated components. In the circuit, diodesD1, D2 and D13 form half-wave rectifiers. The rectified output is filteredusing capacitors C1 through C3 respectively. Initially, when water level isbelow strip L1, the mains supply frequency oscillations are not transferredto diode D1. Thus its output is low and LED1 does not glow. Also, since basevoltage of transister T1 is low, it is in cut-off state and its collector voltageis high, which enables tone generating IC1 (UM66) and alarm is sounded.When water just touches level detector strip L1, the supply frequencyoscillations are transferred to diode D1. It rectifies the supply voltage and apositive DC voltage develops across capacitor C1, which lights up LED1. Atthe same time base voltage for transistor T1 becomes high, which makes itforward biased and its collector voltage falls to near-ground potential. Thisdisables IC1 (UM66) and alarm cannot be sounded. Depending uponquantity of water present in the tank, corresponding level indicating LEDsglow. It thus displays intermediate water levels in the tank in bar-graphstyle. When water in the tank just touches the highest level detector stripL12, the DC voltage is developed across capacitor C2. This enables tonegenerating IC1 (UM66) and alarm is again sounded.
Description
This is the circuit diagram of a simple corrosion free water level indicator for home and industries. In fact the the level of any conductive non corrosive liquids can be measured using this circuit. The circuit is based on 5 transistor switches. Each transistor is switched on to drive the corresponding LED , when its base is supplied with current through the water through the electrode probes.
One electrode probe is (F) with 6V AC is placed at the bottom of tank. Next probes are placed step by step above the bottom probe. When water is rising the base of each transistor gets electrical connection to 6V AC through water and the corresponding probe. Which in turn makes the transistors conduct to glow LED and indicate the level of water. The ends of probes are connected to corresponding points in the circuit as shown in circuit diagram.Insulated Aluminum wires with end insulation removed will do for the probe. Arrange the probes in order on a PVC pipe according to the depth and immerse it in the tank.AC voltage is use to prevent electrolysis at the probes. So this setup will last really long. I guarantee at least a 2 years of maintenance free operation. That’s what I got and is still going.
Water Level.rtf (Size: 5.21 KB / Downloads: 133)
INTRODUCTION
If you need a fully automatic water level controller circuit then try this circuit Water level controller. The circuit is fully based primarily on transistors. The sensing section is somewhat similar to this circuit but there is additional circuitry for switching the pump ON when the water level falls below a set level and the pump will be switched OFF when the tank is full. Few transistors , one 555IC and an electromagnetic relay is used for realizing the control section. The circuit is very simple cost effective , reliable and many guys have successfully assembled it.I am also working on a float type water level indicator/controller using the float type fuel gauge mechanism used in motor cycles.The level sensor section is finished and now I am working on the control circuitry. I will add the circuit here as soon as it is finished.Here is a simple, versatile cir- cuit which indicates the level of water in atank. This circuit produces alarm when water level is below the lowest levelL1 and also when water just touches the highest level L12. The circuit isdesigned to display 12 different levels. However, these display levels can beincreased or decreased depending upon the level resolution required. Thiscan be done by increasing or decreasing the number of level detector metalstrips (L1 to L12) and their associated components. In the circuit, diodesD1, D2 and D13 form half-wave rectifiers. The rectified output is filteredusing capacitors C1 through C3 respectively. Initially, when water level isbelow strip L1, the mains supply frequency oscillations are not transferredto diode D1. Thus its output is low and LED1 does not glow. Also, since basevoltage of transister T1 is low, it is in cut-off state and its collector voltageis high, which enables tone generating IC1 (UM66) and alarm is sounded.When water just touches level detector strip L1, the supply frequencyoscillations are transferred to diode D1. It rectifies the supply voltage and apositive DC voltage develops across capacitor C1, which lights up LED1. Atthe same time base voltage for transistor T1 becomes high, which makes itforward biased and its collector voltage falls to near-ground potential. Thisdisables IC1 (UM66) and alarm cannot be sounded. Depending uponquantity of water present in the tank, corresponding level indicating LEDsglow. It thus displays intermediate water levels in the tank in bar-graphstyle. When water in the tank just touches the highest level detector stripL12, the DC voltage is developed across capacitor C2. This enables tonegenerating IC1 (UM66) and alarm is again sounded.
Description
This is the circuit diagram of a simple corrosion free water level indicator for home and industries. In fact the the level of any conductive non corrosive liquids can be measured using this circuit. The circuit is based on 5 transistor switches. Each transistor is switched on to drive the corresponding LED , when its base is supplied with current through the water through the electrode probes.
One electrode probe is (F) with 6V AC is placed at the bottom of tank. Next probes are placed step by step above the bottom probe. When water is rising the base of each transistor gets electrical connection to 6V AC through water and the corresponding probe. Which in turn makes the transistors conduct to glow LED and indicate the level of water. The ends of probes are connected to corresponding points in the circuit as shown in circuit diagram.Insulated Aluminum wires with end insulation removed will do for the probe. Arrange the probes in order on a PVC pipe according to the depth and immerse it in the tank.AC voltage is use to prevent electrolysis at the probes. So this setup will last really long. I guarantee at least a 2 years of maintenance free operation. That’s what I got and is still going.