 Tustin has shown that the input and output power are the same, and so the machine transforms the constant-voltage input into a constant-current output.As with the metadyne generator, the Metadyne transformer can be partially compensated, and will continue to operate as a constant-current device until the compensation exceeds 97 per cent.The third diagram shows a metadyne connected to two separate motors, and this arrangement was often used for the control of traction motors on electric trains.