Machine Parts For Reuse Newsgroup Discussion Forum   >   Medium Size Parts   >   Non functional   >   Mechanical   >   Build a digital converter 4-8-12-16-24 kw: plans + tips

Build a digital converter 4-8-12-16-24 kw: plans + tips


This is for plans and instructions to build either
1. a rotary converter 4kW (5hp) based on standard parts, no controller needed, or
2. a digital rotary single to three-phase converters between 4kW and 24kW (5hp to 30hp) which requires a special digital controller.
Phase converters are used in metalworking or woodworking workshops, in meat processing, in bakeries, on dairy farms, in print shops.
They run one or several three-phase machines on single phase power.
Non-digital converters can be used with simple machines in a home workshop.
Digital converters are needed when phase voltages balance is wanted (CNC / PLC, plasma cutters, VSDs, welders, high motor output).
Non-digital rotary converters (plan included) do not require a controller but have some minor drawbacks:
- The generated phase output voltage varies with changing loads.
- Contactors wear and may fail after some years.
Digital rotary converters (nine plans are included) offer the best features of all converters today but require a special controller:
* No contactors, no electrolytic capacitors are used.
Digital non-rotary inverters (see our DriveBooster listings) are lightweight but have some drawbacks too:
- in 50Hz networks, machines must be modified electrically before an inverter based system can be used.
- Electrolytic capacitors used have a limited lifetime (shorter at high temperatures).
- Due to rectifiers, the power factor is poor. Not important with smaller inverters.
- Harmonics in input current are high. Not important with smaller inverters.
- RFI (Radio Frequency Interference) filtering is needed to comply with codes.
- EMI (Electromagnetic Interference) requires shielding of output cables.
A standard three-phase induction motor, 2 pole for digital, best would be the new high efficiency type.
If this is to be made for 50Hz: a single phase three-wire step-up autotransformer.
Parts, controllers, complete kits, phone and email support, complete solutions are available from sources in the UK, the US, in Australia, in NZ.
Sources, parts and other details are published (google them) and are also listed in the supplied documents.
Money back guarantee if you are not satisfied.
Three-phase output will be (voltages are unbalanced with non-digital and controller E and balanced with controller T and F):