... ,RS485 5.IEC62053-21 DTSD5168 Three phase electronic multifunction watt-hour meter FUNCTIONS AND FEATURES♦ Front board three fixed holes ... T 645-1997;♦ Five LED instructions separately represent power state, signal of power impulse, the direction of the trend of ... communication state.♦ Detect active and reactive energy, active and reactive power, voltage, current and frequency, etc. of three-phase ...