Digital motor load monitor with built-in CT
The Unipower HPL110 monitors the true kW loading of three-phase motors supplied at 380-440 V. A built-in current transformer allows direct measurement up to 8 A, and adjustable start and reaction timers ensure reliable detection of over-load and under-load conditions. The single SPDT relay trips when the load exceeds or falls below the set limits, protecting pumps, conveyors and other machinery.
Technical Highlights 🔧
- Measuring principle: true kW measurement with built-in current transformer (0.5-8 A).
- Supply/measurement voltage: 3 x 380-440 VAC; frequency 45-65 Hz.
- Adjustable limits: high and low set-points programmable from 5 % to 100 % of full load.
- Timers: start delay and reaction delay 0.1-25 s to avoid nuisance trips.
- Output: one SPDT relay rated 5 A @ 230 VAC.
- Mounting: DIN-rail, IP20 terminals, IP40 housing; dimensions approx 56 mm wide, weight 0.42 kg.
Benefits ✅
- Protects motors from overload or dry-running by measuring true shaft power.
- Internal current transformer eliminates the need for external sensors up to 8 A.
- Wide 380-440 V supply range covers common industrial networks.
- Simple setup via adjustable dials for load limits and timers.
Applications 🚀
- Pump protection against dry-running or blocked impellers.
- Conveyor belt jam detection and overload protection.
- Fan and blower protection in HVAC systems.
The HPL110 provides reliable motor protection by accurately monitoring power consumption and tripping when conditions fall outside the programmed limits.
FAQs
- Q: Does the HPL110 require an external current transformer?
A: No. It has a built-in CT for currents up to 8 A. For higher currents an external N/1 or N/5 CT can be used.
- Q: Can I set different over-load and under-load limits?
A: Yes. Both high and low thresholds are independently adjustable between 5 % and 100 % of full load.
- Q: What is the trip output?
A: A single SPDT relay rated 5 A @ 230 VAC provides a normally open and normally closed contact.