California Instruments RS Series AC/DC Power supplies from Ametek Programmable Power features the ability to both source and sink current to give bi-directional current flow.

The RS amplifier is designed to reverse the phase relationship between the AC input voltage and current in order to feed power back onto the utility grid. This mode of operation is particularly useful when testing “green” grid-tied products that feed energy back onto the grid. In particular, it allows static power converters such as grid-tied and off-grid photovoltaic inverters to be tested for frequency variations, voltage transients, DC injection and harmonic susceptibility.
The RS90 delivers up to 90kVA of AC or AC + DC power. In DC mode, 50% of the AC power level is available. For higher power requirements, the RS180, RS270, RS360, RS450 and RS540 models are available, all of which allow separation of the high power system into individual RS90 units for use in separate applications.
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