Meatrol Mi550 vs Fluke 1736/1738: Three-Phase Power Logger Comparison

Where the measurements are equivalent

For the work most buyers of these instruments actually do — logging a building’s load profile for a week, finding peak kVA demand, checking phase balance, verifying power factor, and sizing a solar PV or backup system from real consumption data — the Mi550 and the Fluke 1736/1738 produce the same answers. Both log all three phases plus neutral with flexible Rogowski coils, both record voltage, current, active/reactive/apparent power, power factor and energy per phase, both capture harmonics to the 50th order, and both meet IEC 61000-4-30 Class S. The Mi550’s data exports as open CSV files that work in Excel, Python or any analysis tool, and AmpX includes a free Excel template that produces load-profile and peak-demand graphs without any additional software licence.

Where the Fluke is genuinely better

Honesty matters in a comparison, so here is where the Fluke justifies its price. The 1736/1738 can be powered directly from the circuit being measured, which matters for long unattended installs in panels with no socket nearby — the Mi550 needs its 5 V supply or runs about 10 hours on batteries. The 1738 adds WiFi and Bluetooth with the Fluke Connect app for live remote monitoring, and an EN50160 Power Quality Health Summary that produces standards-compliance reports some industrial clients specifically request. The Fluke also accepts up to 1000 V rms directly (the Mi550 tops out at 690 V L-N without a voltage transformer) and logs at intervals down to 1 second versus the Mi550’s 5 seconds. If your work regularly requires any of those four things, buy the Fluke — it is an excellent instrument.

Where the Mi550 wins

The obvious one is price: a complete, working kit for €1,360 versus €6,000+ for the Fluke — and on Fluke /BASIC models the flexible current probes still cost extra. But there are practical advantages beyond price. The Mi550 kit includes magnetic voltage probes that snap onto breaker screws, which makes live installation in a crowded cabinet faster and safer than alligator clips alone. It has built-in Ethernet with Modbus TCP as standard, so it drops into SCADA and building-management systems without extra modules. Its waveform recorder samples at up to 8 kHz. And because AmpX stocks parts and repairs Meatrol instruments locally in Germany and South Africa, a fault means a swap-out under the 2-year warranty rather than weeks at an overseas service centre. Each Mi550 is factory-calibrated, and a TÜV calibration certificate is available on request — the same traceability an established brand provides.

The bottom line

If you invoice clients for compliance-grade EN50160 studies, need circuit-powered unattended logging, or your customer mandates a specific brand, the Fluke 1738 is worth its price. For everyone else — electricians doing load studies, solar installers sizing systems, consultants running energy audits, facility managers checking capacity before adding EV chargers or heat pumps — the Meatrol Mi550 measures the same parameters to the same standards class, arrives as a complete kit, and leaves roughly €5,000 in your pocket. That difference pays for a lot of site visits.