How will a Re:load Pro handle an AC current? Or, more accurately, a pulsating DC current.

I appreciate that it's designed for DC applications but I want to production test a unit that outputs an AC signal. Turning the AC into DC is easy, a bridge rectifier will do that and leave the current untouched, but I'm then left with the issue of how well controlled the current will be. And what relationship the displayed current will have to the actual current flowing.

The Re:load Pro will attempt to maintain a constant DC current flow. That means that as the AC voltage decreases, the Re:load Pro's resistance will decrease to keep the current constant. When it gets near 0, it won't be able to maintain that.

This is in contrast to what an actual AC load would do - its current draw will vary at the same frequency (though not necessarily in phase) as the source. If you wanted the Re:load to behave like this, you could potentially use a bridge rectifier followed by a large capacitor.