When designing a grid powered product, you should consider various points that can impact the behavior of your product or even the grid.
A short list of some possible misbehaviors:
- Strange behaving engines
- Humming
- False speeds
- Flickering displays
- Misbehaving AC/DC converters
- Phase shifting
- Generating Harmonics
There are some recommended tests - but how to conduct them? You can’t just plug the device into the next socket and see if it is working or not.
Another issue is that the plug and voltage standard differ in many countries. In Japan, for example, the mains supply is between 50Hz and 60Hz, so you should test your product on both frequencies if you want to sell there. In such cases, an AC-Power supply comes in handy.
Let us have a closer look at two other examples:
Example 1: Coffee Machine for Colombia (110V / 60Hz)
Imagine that you are a coffee machine manufacturer who wants to sell in Columbia. First, you should consider the specification of the local power grid, which is 110 volts and 60Hz. So you can’t just plug this coffee machine into, for example, a Swiss power grid (230V / 50Hz).
How would you then test your coffee machine?
- Using one (or several) power plugs
- Or measuring with an AC-Source
Using power plugs:
The output of your power plug might have a voltage about 110 volts and frequency of 60Hz. But you have only one single test point where your coffee machine works.
Test with an AC Source:
You can test the output on a whole range of voltages and frequencies. If your coffee machine works on up to 127 volts you can sell it in countries that operate on higher voltages, like the United States or Ecuador.
Other tests might be if your coffee machine generates harmonics, the reaction to voltage drops, the behavior of inconsistency in frequency and many more.
The various test scenarios can ensure that your coffee machine works under almost any circumstances in several other countries.
Example 2: Electrical 3-Phase Engine for Germany (3x 400V / 50Hz)
Designing a large electrical engine is a challenging task. But with a particular size, you should use an electrical connection with three phases. Three times 400 Volts, right?
Well, on paper, yes, but you might run into grid fluctuations of several percent.
Other controlling methods for testing the electrical engines:
- Direct control
- Wye-delta starter
- Soft starter
- Frequency converter
Each type of engine control has its own advantages and disadvantages. It is too risky connecting directly to the local grid.
Powering your engine and doing the corresponding engine control by using a three-phase AC power supply helps you to detect and solve a wide range of possible issues.
You might test the following:
- Behavior on voltage fluctuation
- Behavior on frequency fluctuation
- Balancing of your three phases
- Phase shifting
- Behavior if a phase is interrupted
- Generated harmonics
- Grid load on the activation
- Efficiency
- Energy consumption
Conclusion:
If you design a grid powered product, consider to test it by using an AD-Source, like the high performance programmable IT7600.
An AC-Source not only helps you to examine the functionality in a particular environment but also to find any negative influences created by your product.