What would be a good load for testing ?

[FreshmanNewbie]

I have a board that gives out 3-phase voltage output.

Output 3 phases. Each phase will give 220V with respect to neutral. So, it is a 3-phase 4-wire system on the output.

I want to test this board.

What would be a good load to test whether all three phases are coming with the right voltage in a lab?

Also, the board has a residual current detector. I want to test that residual current detector which should indicate when there's some leakage between any one of the 3 phases and neutral.
Any idea on how to test this residual current (how to establish an artificial leakage) and what would be an appropriate 3-phase load that can be commonly available in electrical labs?

 

[KlausST]

Hi,

it depends on what item or functionality you want to test.

Without knowing details I recommend to use the load it is designed for.

Klaus

 

[D.A.(Tony)Stewart]

Inverter specs?: Power Specs? W, pf?

Leakage current to PE gnd =can be R or C or RC value

Load can be passive R, reactive RC or L/R or variac dynamo or active load. Heater?

AC active load with 3 phase triac or ACDC rectified to Active DC load with forced air heatsink using CC sink or RC reactive load.

Always use design specs to test and validate design.

We call this a DVT report. (Design Validation Test)

1 page per test with conditions, specs and results and with block diagram on opposite page.

 

[BradtheRad]

What would be a good load to test whether all three phases are coming with the right voltage in a lab?

Try attaching an LED to each supply wire. Limit 10mA current to led's via series resistor (33k, rated ~3 W). Add a safety diode to prevent exposing led's to reverse voltage.

If all 3 supplies are correct polarity then the three led's light in sequence (in 1/50th of a second). However if one of the supplies is reverse polarity, then it alters the sequence so all 3 led's are dark simultaneously (each 1/50th second).

LED's are their own voltage regulator. By hooking up ~220 ohms across each led, you create voltage dividers with the 33k resistor. Each AC waveform must be sufficient amplitude to light an led.

Link to Falstad's website.
My schematic loads and runs in the animated interactive simulator:

tinyurl.com/yn8dqly5

You can change the load to a 60 W incandescent bulb since it's resistive and can run on DC. In that case the resistor across each led should be reduced to a few ohms, that is, just enough to illuminate the led.

 

[Externet]

Three 220V light bulbs, one at each phase respect to neutral should reveal if phases work.

 

[D.A.(Tony)Stewart]

If you do not answer my questions or give full design specs, how can you know how to test it?