Energy measurement in injection moulding machines is no easy task. The potential sources of errors are extremely wide-ranging and extend from suitable measuring technology through to correct procedures as well as systematic evaluation and interpretation of the results, particularly when it comes to making comparisons.
The power meters that are used for energy measurements on injection moulding machines have high standards to meet. Equipment such as frequency converters, switched mode power supplies and bridge rectifiers cut off the current wave form, resulting in power meters that require sinusoidal voltages and currents delivering incorrect results. This risk primarily affects cheap devices.
- Use only power measurement devices that can also evaluate non-sinusoidal voltages and currents
- Take safety considerations into account: only have measurements performed by the relevant authorised persons
- Only begin with the measurements once the machine has been running in automatic operation for longer than 15 minutes (without changes to parameters or malfunctions)
- Perform measurement for at least 30 minutes to reliably compensate for process-dependent fluctuations
- During machine comparisons of an identical process (mould, material, environment), ensure that an identical measuring principle (port) and identical scope of measurements (without peripherals) are used
- Use specific energy requirement as key parameter: take into account the performance of the machine
- Detailed further training: bring responsible employees up-to-date with ARBURG training course