Universal motor load monitor with true kW measurement
The Unipower HPL500 protects motors by measuring true power on single-phase (100-400 V) and three-phase (100-575 V) supplies. It uses a built-in 40 A current transformer and four-quadrant multiplication to maintain accuracy even when fed from variable-speed drives. Programmable high and low limits with start and reaction timers drive a single SPDT relay, while an isolated 0/4-20 mA analogue output provides proportional load feedback.
Technical Highlights 🔧
- Supply/measuring voltage: 1x100-400 VAC or 3x100-575 VAC.
- Current range: 0.5-40 A via built-in CT; external N/5 CTs up to 600 A.
- Output: isolated 0(4)-20 mA analogue output (max load 400 ohm) and SPDT relay rated 250 VAC/5 A.
- Accuracy class: 2 %; frequency range 45-65 Hz.
- Timers: adjustable start and reaction delays for high and low set-points.
- Housing: DIN-rail 110 x 56 x 75 mm; IP20 terminals; weight ~250 g.
Benefits ✅
- Protects motors against overload and under-load by measuring true shaft power.
- Universal voltage range suitable for single-phase or three-phase networks worldwide.
- Built-in CT measures up to 40 A directly and external CTs extend the range to 600 A.
- Isolated analogue output provides real-time load feedback for control systems.
Applications 🚀
- Pump and compressor protection with adjustable load limits.
- Conveyor systems and crushers driven by variable-speed drives.
- Energy monitoring and process control requiring analogue load signals.
The HPL500 offers flexible and accurate motor protection across a wide voltage range, with analogue output for integration into automation systems.
FAQs
- Q: Can the HPL500 operate on single-phase supplies?
A: Yes. It supports both single-phase (100-400 V) and three-phase (100-575 V) systems.
- Q: How is the analogue output configured?
A: The 0/4-20 mA output is scaleable to represent any kW range up to the maximum measured and is galvanically isolated.
- Q: Does the HPL500 include more than one relay?
A: This model provides a single SPDT relay. Dual-relay and Modbus versions are available (HPL500MB).