A 175mm tall, high voltage generator that will achieve 30,000 to 40,000 volts of “static” electricity. With no mechanical parts. The Cockcroft Walton Multiplier is a safe, current limited high voltage generator for home lab or classroom. It is capable of providing the high voltage for all the experiments that can be done with the 150mm Van De Graaff. As there is no reliance on triboelectric charging it does not require the low humidity and scrupulous cleanliness of a VDG and so removes many of the problems associated with traditional Van de Graaff experiments.
The Cockcroft Walton Multiplier comprises of a 6V battery pack, which powers a single transistor switch mode power supply. This drives a transformer to give a high AC voltage. This AC voltage is fed into an arrangement of 6 diodes and 6 capacitors that multiply the transformers peak output voltage by three times. This is enough to give an output voltage of roughly 35000 volts. An arrangement of series resistors and the switch mode power supply, limit the current that can be drawn from the CWM to less than 0.5mA. This is well below the recommended maximum current that will cause problems in heathy people. It will however produce quite a tingle, so repeated direct contact should be avoided. The charge is smaller than you can pick up walking across a carpet on a dry day. But this is enough to get sparks to fly 15-20mm.
Unusually for a Cockcroft Walton Multiplier the high voltage is delivered to a small Van de Graaff style dome to ease its use with experiments intended for a classic small VDG
This Cockcroft Walton Multiplier kit is designed for kids (with the help of adults), Adults and Teachers to learn about “static” electricity and making/soldering an electronic PCB based kit.
The kit is supplied as a PCB with electronic components that will need soldering with a stainless steel ball and an acrylic case that requires screwing together.
Cockcroft Walton Multiplier kit Specifications
Input Voltage: 6-12V @ 1000mA(minimum)
Output Voltage: 30,000 to 40,000V (unloaded)
Height: 180mm (7″)
Top Ball Diameter: 65mm
Top Ball: Polished Stainless Steel
Current regulation: Switch mode and resistive to a MAX of 0.4mA (continuous)
Output Capacitance: (worst case): 40pF = 33pF (multiplier) + 7pF (dome)
Earth: 4mm Banana plug
Transformer: 10KV(High frequency, RMS)
Multiplier Stages: 3 (6 diodes, 6 Capacitors)
Construction Details: CWM Resources
Experiments :Franklin’s bells, Jumping Rice, Electric Wind, ping-pong ball cyclotron. See the resources section for more details.
Sorry, Batteries are not included.
Although the voltages produced by product are safe for humans, this is not true for any other electronic device. IT MUST NOT BE USED WITHIN 300mm OF ANY ELECTRONIC EQUIPMENT. Also be aware whilst using the device you may pick up electrostatic charge, do not operate any electronics whilst using the device. You are a conductor.
Do not use if you have a pacemaker, cochlear implant or and electronic controlled medical device.
Does contain small parts and is therefore not suitable for small children.
This device is not intended to be run from an external power supply, and it is UNSAFE to do so.
This device should not be used to charge capacitors or external electrical storage devices.