The original Manta protective relay test system that set the industry standard. Covers the complete spectrum of relay testing with the ability to test, evaluate, calibrate and commission all types of protective relays. This test system series includes the core MTS-1710 single-phase test system. It can be expanded with the MTS-1720 two-channel current source to allow complete three-phase testing. It can be further expanded with the MTS-1730 to digital inputs and outputs to the test system.