Fluke 1738 Power Logger (three-phase energy logger)

Three-phase energy logger for load studies, power consumption assessment and basic power quality measurements. It records voltage, current, power, energy, harmonics and voltage events for many weeks, and makes the results available via USB storage, Wi-Fi or the Fluke Connect app without opening the switchboard.

Unlike a power quality analyzer, it is designed primarily for multi-week recording of load profiles, energy use and voltage events. Its intelligent connection verification function detects and corrects common probe connection errors, while power from the measured circuit eliminates the need for an external outlet.

In non-traction auxiliary-service switchboards, the logger measures available power capacity before adding new loads, load profiles of onboard auxiliary converters and sources of current distortion in signalling equipment supplies. Current probes must be selected for the conductor size and expected current.

Specifications (Fluke 1738, from the 1736/1738 datasheet):

• Measurement category (CAT) - CAT IV 600 V / CAT III 1000 V
• Voltage inputs - 4 (three phases and N), max. 1000 V rms, accuracy ±(0.2% + 0.01%)
• Current inputs - 4; i17xx-flex probes 1500 A / 3000 A / 6000 A or i40s-EL 40 A clamps
• Recorded parameters - voltage, current, power, power factor, energy, THD (total harmonic distortion), harmonics, events (dips, swells, interruptions, inrush current)
• Power quality measurement method - IEC 61000-4-30 Class S, IEC 62586-1 (PQI-S); harmonics IEC 61000-4-7 Class 1
• Compliance assessment - EN 50160 for measured parameters (PQ Health function)
• Memory - typically ten 8-week sessions at 1-minute intervals
• Power supply - 100–500 V from the measured circuit or 100–240 V via an IEC 60320 lead; 3.7 V Li-ion battery
• Operating temperature - –10 °C to +50 °C; IP50 rating
• Weight - 1.1 kg (instrument), 400 g (power supply)