Unipower HPL500 & HPL500MB: Beyond Overload Protection
In industrial automation, basic overload relays do not provide the insight that modern plants demand. The Unipower HPL500 changes that. Built for intelligent supervision, it measures true power (kW) at the motor and helps you optimise the process, not just avoid trips.
Available from Charter Controls, the HPL500 family suits conveyors, pumps, mixers, and process machinery where early fault detection and energy visibility matter.
Universal Power Measurement with Global Flexibility
The HPL500 operates on 100–575V AC, single or three-phase, with internal current sensing up to 40A (or up to ~600A with external CTs). It uses fast, four-quadrant multiplication of voltage and current to compute real power accurately — including on VFD-fed systems — so you see the actual mechanical load, not just amps.
New: HPL500MB — Native Modbus for PLC/SCADA
If you want live kW, % load, alarms and diagnostics in your PLC or SCADA, choose the HPL500MB variant with RS485 Modbus RTU. It gives you:
- 🔌 Direct RS485 Modbus RTU connectivity to PLC/SCADA/BMS
- 📊 Live telemetry: kW, % load, min/max capture, status and alarms
- 🛠️ Remote parameterisation: read/write key setpoints and timers (where enabled)
- 🧪 Commissioning aid: trend real power while tuning alarm limits
- 🔁 Easy retrofit: drop-in wiring (before inverter if present), minimal field sensors
Result: HPL500MB upgrades a stand-alone load monitor into a networked diagnostic instrument for predictive maintenance and OEE dashboards.
Key Features (HPL500 / HPL500MB)
- ✅ Universal voltage: 100–575V AC, 1~ or 3~
- ✅ Internal current: 0.5–40A (to ~600A via CT)
- ✅ True kW display: real-time kW and % kW
- ✅ Peak detectors: capture run minima/maxima for fast setup
- ✅ Programmable timers: start & reaction delays to avoid nuisance trips
- ✅ Dual limits: independent max/min limits for dry-run, jam, overload, etc.
- ✅ Analogue output 0/4–20 mA: process feedback to PLC/SCADA
- ✅ DIN-rail mount: compact 110 × 56 × 75 mm
- ✅ Approvals: CE, UL (File E194022), GOST-R
- 🧠 HPL500MB only: RS485 Modbus RTU (data into PLC/SCADA)
Smarter Control Than Simple Overload Relays
Overloads react to current; the HPL500/HPL500MB reacts to true power, so it flags process problems earlier:
- 🚿 Pumps — detect cavitation/dry-run immediately
- ⚙️ Conveyors — identify jams and torque spikes
- 🧪 Mixers/agitators — track viscosity changes via kW
- 🪵 Processing lines — monitor product/load variation
Built-In Intelligence for Process Optimisation
With dual setpoints, timers, and an analogue output, the HPL500 family lets you control by kW — alarm, interlock or optimise based on shaft power rather than current. Enter motor efficiency to calculate shaft output power (P2) in real time.
Formula: P2 = P1 – P0 (shaft power = input power – motor losses)
Technical Specifications
- Supply/Measurement: 100–575V AC (1~ / 3~), 45–65 Hz
- Current: 0.5–40A internal; higher via external CT
- Accuracy: Class 2
- Output (analogue): 0(4)–20 mA, isolated, 400 Ω max load
- Relay Output: 250V AC / 5A
- Protection: IP40 housing, IP20 connectors
- Dimensions: 110 × 56 × 75 mm
- Approvals: CE, UL508, GOST-R
- HPL500MB communications: RS485 Modbus RTU (live kW, % load, status, alarms; parameter access where enabled)
Why It Matters
HPL500/HPL500MB helps engineers move from reactive protection to proactive optimisation: earlier fault detection, energy visibility, and smoother running — all from a compact, panel-mounted device. Choose HPL500MB when you need native PLC/SCADA integration.
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Unipower (UK) Ltd trading as Charter Controls — Simplifying Industrial Automation for the UK and Ireland.