Beyond Vibration: Electrical Signature Analysis and Online Oil Monitoring for Motors, Gearboxes and Compressors

Why one technology is never enough

Maintenance teams in ASEAN often start with vibration – rightly, because it covers the most common faults. But two expensive failure modes stay invisible to accelerometers until very late: a motor with a cracked rotor bar can vibrate normally until the bar breaks, and a gearbox can shed bronze and steel particles for months before tooth damage changes the vibration spectrum. Adding electrical and oil analysis closes those gaps, usually on a small number of high-value assets.

Electrical signature analysis (ESA)

ElectroSine measures three-phase current and voltage at the MCC or VFD output and analyses the spectrum and waveform continuously. Because it is installed in the switchroom, it suits motors that are hard or dangerous to reach: submersible and borehole pumps, motors in hazardous areas, cooling-tower fans, motors on moving equipment.

• Rotor faults – pole-pass sidebands around line frequency indicate broken or cracked bars long before failure.
• Stator and insulation – current unbalance and harmonic patterns point to winding degradation.
• Supply quality – voltage unbalance above 2 %, harmonics from VFDs and under-voltage during peak hours are frequent in industrial estates; they overheat motors and are invisible to vibration.
• Load and process – torque ripple reveals pump cavitation, belt slip and gear problems through the motor’s own current.
• Energy – real power and efficiency per motor without separate meters.

Online oil condition monitoring

Poseidon Trident counts ferrous and non-ferrous particles, measures water content and oil temperature in the lubrication or hydraulic circuit, and reports ISO 4406 cleanliness codes (for example 18/16/13) in real time. Trends matter more than single values: a jump of two ISO codes in a week means a bearing or gear is wearing, water ingress after monsoon rain means a seal or breather has failed. Typical ASEAN applications are palm-oil mill gearboxes, cement mill reducers, paper-machine drives, hydraulic presses in automotive plants and air compressors in electronics fabs.

Selecting the right mix per asset

From data to decisions

All three streams land in PlusSmart Analytics, which correlates them per asset: a rising ISO code plus a new gear-mesh sideband is a confirmed gearbox problem; a supply unbalance alarm across ten motors points to the transformer, not the motors. Reports are reviewed with your team monthly; alerts go to WhatsApp, email or your CMMS.

Start small

A typical first project in Thailand or Indonesia covers 5–10 assets that have failed twice in two years – one ESA unit on the worst motor group, one oil monitor on the most expensive gearbox, i-ALERT on the rest. Tell us the assets and failure history and we propose the mix, cost and schedule. Related reading: wireless vibration pilot · pump reliability · country pages for Thailand and Indonesia.