Video: Nexus 1450 – Product

Video transcript

Why the Nexus 1450 has a separate display, and what it brings to a switchboard: class A power quality, billing accuracy and 6 communication ports, in a meter built to be cyber secure. Many switchboards still carry older meters, and replacing them usually means cutting the panel door. The Nexus 1450 avoids that: its transducer base mounts behind the panel as a direct replacement for the previous 125x series, and its display fits the openings left by the old analogue meters. Four figures sum it up:

0.06% energy accuracy, class A power quality to IEC 61000-4-30, waveforms at up to 1024 samples per cycle, and 6 communication ports working at once. Each current input carries two sensors, one high gain and one low gain, measuring at the same time. The meter reads the signal level and uses the better one. It picks up from one milliamp and reaches full accuracy at 25, so the error stays flat exactly where a feeder spends most of its hours: at low load. And the same meter serves 5 amp and one amp C Ts.

Parameter by parameter: voltage and current to 0.04% of reading, active power and energy to 0.06, reactive power and power factor to 0.15, and frequency to 1000th of a hertz. For billing it measures in all 4 quadrants, with maximum and minimum values time-stamped. It compensates transformer and line losses, gives coincident readings such as the power factor at the moment of peak demand, adds gas and water meters through pulse inputs, and handles complex contracts with a perpetual time-of-use calendar.

Power quality is measured to class A, which makes the readings comparable between instruments and admissible in a contract dispute. Dips and swells are recorded with microsecond resolution, harmonics go up to order 511, and the meter itself calculates the weekly EN 50160 report. Waveforms are captured at up to 1024 samples per cycle, with the cycles before and after the event and faults up to 8 times full scale. Even without any configuration, an internal database logs 172 parameters, and 8 more historical logs of 64 channels are there for whatever the site needs.

Two keys set the capacity. V1 gives 512 megabytes of logging memory and 512 samples per cycle. V2 raises that to 1200 megabytes and 1024 samples, and adds IEC 61850 with GOOSE messaging. At a fifteen-minute interval, each log covers 163 or 327 days. Around the metering, the base carries 8 digital inputs, an auxiliary voltage input and two pulse outputs as standard, and 6 ports: Four serial and two Ethernet, one of them in fibre.

Modbus, DNP3 and IEC 61850 run at the same time. It is built to be cyber secure. Passwords of up to 32 complex characters, encryption, and lockout after failed attempts. One administrator and 10 users in 4 roles. A physical sealing switch, firmware that is verified before it is accepted, and a log that records any attempt at tampering. And the meter serves its own web dashboard, in HTML 5:

real-time readings, trends, waveforms, phasors and flicker, on a PC, a tablet or a phone, with no extra software. It fits where an older switchboard meter has to be replaced without touching the panel, and wherever a substation or an industrial distribution board needs class A quality, reliability studies and a solid link to SCADA. In figures: 20 to 720 volts between voltage inputs, class two and class 20 current in one configuration, and operation from minus 25 to plus 70 degrees. Power network analysers, from Amperis.