A low power ozone maker circuit uses a small amount of electricity to create ozone gas.
This gas is made by zapping regular oxygen molecules O2 in the air with strong electricity, splitting them into ozone O3.
Ozone can be helpful for cleaning the air, water and even killing germs.
However, it is important to be careful because too much ozone can be harmful.
Circuit Working:
Parts List:
| Category | Item | Quantity |
|---|---|---|
| Capacitors | PPC 68nF 630V | 29 |
| Semiconductors | Diode 1N5408 | 1 |
| Diodes 1N4007 | 28 | |
| Other Components | Fuse 2A | 1 |
| Touchproof chamber (see text) | 1 |
Ozone and negative ions can be produced in the air using a corona discharge method.
This involves using a sharp negatively charged tip in proximity to a flat metal part with a positive or neutral charge.
The device created through this process generates negative air ions and ozone.
The ozone helps combat decay and mold and can freshen up damp musty air in places like basements or areas with bacteria, fungi or unpleasant odors.
A cascade system which converts high DC voltage from grid voltage is a simple quiet and more efficient alternative to typical flyback converters.
The capacitors 68nF, 630V are placed on the upper side and the diodes are placed on the underside of perforated boards without copper islands just the pure plastic board.
There are 15 capacitors in the negative branch and 14 in the positive branch requiring a total of 29 diodes.
To prevent unwanted corona discharge, connection spots for high voltages are carefully rounded and deburred, with all sharp edges coated with epoxy glue to reduce the field strength below the corona level.
The diodes used can be 1N4007 except for the first one which should be 1N5408 or a similar type to handle the initial current peak when the device is switched on.
Using a 1N4007 for this first diode could result in damage and fuses rated below 2A may blow.
This aspect is often overlooked in schematics found in books and online.
For safety, I constructed a fully insulated and touch proof casing using plexiglass assembled with UHU PLAST and used polyamide screws for the lid and PC board.
The discharge elements were initially graphite inserts from rechargeable pencils on the negative side and a brass ring on the positive side enclosed in a glass chimney.
The chimney is designed so that it is impossible to touch the discharge parts but it is not tamper proof.
To avoid accidents, it is advisable to switch off the device and remove it from the room if there are small children present.
To address issues with the graphite inserts overheating and causing flashovers I replaced them with hardened steel nails against zinc plated steel washers.
This modification also creates a good ion wind and updraft in the chimney eliminating the need for a fan.
The distance between the tips should be adjusted to produce a visible and audible corona discharge in normal air conditions without sparking over in higher humidity.
The tips should emit a faint blue light in the dark indicating correct operation at a distance of about 5 to 7mm.
This device is suitable for a large living room but is too powerful for a small room or continuous operation.
It consumes 0.35mA from a 230V 50Hz grid.
When generating ozone it is important to switch off the device before entering the room if there are no humans or animals present.
The correct concentration of ozone is when the air feels fresh upon entering the room without a distinct ozone smell.
Ozone levels are too high and become unhealthy if they cause coughing, teary eyes or a runny nose.
It is slightly above the limit if you can detect ozone in the air.
Measurement should be done by stepping outside for a while then entering the room taking a deep breath and assessing the air quality.
Over time 6 to 12 months the tips will become dull and the zinc on the washers will convert to zinc oxide which does not affect performance.
Cleaning the device and sharpening the tips annually is recommended.
Using stainless steel washers of seawater resistant quality can extend their lifespan.
Formulas:
The formula for a Cockcroft Walton voltage multiplier.
The following formula may be used to get the output voltage Vout of a cockcroft walton voltage multiplier under ideal circumstances (no ripple voltage, no voltage drops across diodes, and negligible load current):
Vout = 2 * n * Vpeak
where,
- The output is called vout.
- The number of stages (or pairs of capacitors) in DC voltage is n.
- Vpeak is the AC inputs peak voltage.
The output voltage is really lower for a number of reasons.
A more precise calculation that takes these things into consideration is:
Vout = 2 * n * Vpeak – (n + 1) * Vd – Vr
where,
- The typical voltage drop across a diode is Vd.
- The ripple voltage is denoted by Vr.
While precise ozone production calculations can be complicated and dependent on a number of variables, the following basic connections can be taken into consideration:
Voltage Multiplier Capacitive:
Vout = N * Vin
where,
- Output voltage Vout is approximately equal to the input voltage Vin multiplied by the number of stages N
Note:
This formula may not always be accurate, but it gives a decent estimate in most situations.
Experiments or simulations are frequently needed for accurate calculations and optimization.
How to Build:
To build a Simple Low Power Ozone Generator Circuit follow the below mentioned steps for connections:
Corona Discharge Assembly:
- Place the sharp negative tip near the flat positive or neutral metal part.
- Ensure there is a small gap about 5 to 7mm between them to produce a visible and audible corona discharge without sparking over in high humidity.
Capacitor and Diode Configuration:
- Capacitors should be placed on the upper side of perforated boards without copper islands and diodes should be placed on the underside.
High Voltage Generation:
- Use a high voltage transformer or circuit to generate the high DC voltage required for the corona discharge.
- This circuit should convert grid voltage to a higher voltage suitable for the multiplier.
Insulated Casing:
- Construct a fully isolating and touch proof casing using plexiglass.
- Use UHU PLAST and Polyamide screws for assembly.
- Ensure the casing encloses all components safely.
Discharge Element Modification:
- If using graphite inserts glue them into a brass holder with a mixture of graphite powder and lacquer.
- For improved safety and performance consider replacing them with hardened steel nails acting against zinc plated steel washers.
Safety Measures:
- Round and deburr all connection spots for high voltages to avoid corona discharge at unwanted locations.
- Paint over sharp edges with epoxy glue to reduce the field strength below the corona level.
Testing and Adjustment:
- Test the device to ensure it generates ozone and negative ions effectively.
- Adjust the distance between the sharp tip and metal part to achieve the desired corona discharge characteristics.
Maintenance:
- Clean the device and re sharpen the tips annually.
- Consider using stainless steel washers for longer lifespan.
Note:
- Building such a device requires knowledge of electronics and high voltage safety.
- Exercise caution and adhere to safety guidelines when working with high voltages.
Conclusion:
A low power ozone generator circuit is a compact and efficient device that uses high voltage to generate ozone gas for various applications.
It typically consists of a high voltage power supply ozone generation chamber, control circuitry and safety features to ensure safe operation.
These circuits are designed for applications where a small amount of ozone is needed such as air purification and water treatment.