Power Monitor

Online Power Monitoring Systems for Transformers, Switchgear and Cables
This section covers the online monitoring side of the catalogue: 21 permanently installed instruments that watch an asset continuously instead of testing it once. They are grouped into transformer monitoring (7), switchgear monitoring (5), power quality monitoring (5) and cable monitoring (4).
These are installations, not hand tools, and the specifications reflect that. Typical units accept 100–240 V AC or a DC supply, are rated to IP66 for outdoor cabinets, work from −40 °C to +70 °C, and report over RS485 as standard with optional 4G, Wi-Fi or 4–20 mA outputs. Measurement performance follows the asset: dissolved gas units track up to nine gases and moisture in transformer oil; partial discharge channels reach a stated sensitivity of ≤1 pC across a 100 kHz–100 MHz band; temperature chains resolve 0.1 °C with ±0.3 °C accuracy on fluorescent fibre probes and ±0.5 °C on Pt100; and channel counts expand from 3 up to 64 sensors on one unit.
What each group monitors

Transformer monitoring — dissolved gas analysis, partial discharge, winding hot-spot temperature, core and clamp earth current, bushing condition, vibration and physical intrusion. See the HF-T-602 transformer DGA online monitoring system and the HF-T-603 transformer partial discharge online monitoring unit.
Switchgear monitoring — SF6 gas density and leakage, busbar and contact temperature, and internal partial discharge. Example: the HF-W-701 SF6 gas density monitor.
Cable monitoring — continuous partial discharge, sheath grounding current, conductor and joint temperature, and fault location on HV lines. Example: the HF-C-203 cable temperature online monitoring system.
Power quality monitoring — harmonics, voltage fluctuation, three-phase unbalance and waveform recording, single or multi-channel. Example: the HF-PQ-202 dual channel power quality monitor.

Sample intervals, alarm thresholds and communication protocol are usually the points that decide a project, so it is worth confirming them before you order. Tell us the asset, the gas or parameter list you need to trend, and how the data will be collected (SCADA, cloud platform or local display) — we will map that onto the models in this section.
Every instrument in this range is sourced from qualified partner factories in China, verified and tested against its datasheet before shipment, and delivered with its test documentation. Houfeng is a trading company and supplier — not a manufacturer.