What is True Power?
True Power (active power) is the electrical power actually used by equipment to perform useful work, measured in watts (W) or kilowatts (kW). In AC systems it is calculated as Voltage × Current × Power Factor (cos φ). Monitoring true power provides a more accurate measure of motor workload and system performance than current alone.
Why Measure True Power Instead of Just Current?
By sensing power (volts × amps × power factor) rather than just amps, there is much greater sensitivity. For loss of
load detection, this means a 10× improvement in responsiveness.
Higher sensitivity
Measuring true power (kW) detects load changes much more effectively than monitoring current (amps) alone.
Better low-load detection
Current sensors often miss subtle conditions such as dry-running pumps or lightly loaded conveyor jams, while true power captures these changes.
Linear response across loads
True power sensing provides consistent sensitivity at both low and high load levels, improving monitoring accuracy.
Up to 10× more sensitive
In light-load conditions, power-based monitoring can be up to 10 times more sensitive than current-only measurement.
Load Controls True Power Products
Load Controls builds its products around true power sensing technology. By sampling one phase voltage and the remaining phase current, their sensors compute real power (V×I×PF) on the fly
Universal Power Cells (UPC)
Load Controls’ Universal Power Cell (UPC) sensors measure true motor power (kW) with up to 10× greater sensitivity than traditional current transformers. The compact device installs easily by passing the three-phase lines through the sensor, where built-in Hall-effect technology measures voltage and current directly. It outputs a 0–10 V or 4–20 mA signal representing real-time motor load.
Key Features
- Adjustable range: Scales from a few kW up to ~150 HP.
- High voltage support: Operates up to 600 VAC, including VFD systems.
- Fast response: Detects rapid load changes (4 ms–8s).
- Easy integration: Analog outputs with optional Modbus/IIoT connectivity.
Pump Load Controllers (PMP-25)
The PMP-25 Pump Protection Controller monitors true motor power to detect pump conditions like dry running, cavitation, or blockages more accurately than current-only monitoring. It calculates real power using a 120 VAC voltage sample and motor current, allowing fast response to load changes.
Key Features
- Digital display: Shows load in % load, HP, or kW.
- Dual trip relays: Adjustable low and high setpoints for fault protection.
- 4–20 mA output: Integrates with PLC or SCADA systems.
- Compact design: Easy mounting on panels or starter doors.
- Motor support: Range finder toroid for motors up to 50 HP (external CTs for larger motors).
Load Controls True Power Products
Load Controls builds its products around true power sensing technology. By sampling one phase voltage and the remaining phase current, their sensors compute real power (V×I×PF) on the fly
Universal Power Cells (UPC)
Load Controls’ Universal Power Cell (UPC) sensors measure true motor power (kW) with up to 10× greater sensitivity than traditional current transformers. The compact device installs easily by passing the three-phase lines through the sensor, where built-in Hall-effect technology measures voltage and current directly. It outputs a 0–10 V or 4–20 mA signal representing real-time motor load.
Key Features
- Adjustable range: Scales from a few kW up to ~150 HP.
- High voltage support: Operates up to 600 VAC, including VFD systems.
- Fast response: Detects rapid load changes (4 ms–8s).
- Easy integration: Analog outputs with optional Modbus/IIoT connectivity.
Pump Load Controllers (PMP-25)
The PMP-25 Pump Protection Controller monitors true motor power to detect pump conditions like dry running, cavitation, or blockages more accurately than current-only monitoring. It calculates real power using a 120 VAC voltage sample and motor current, allowing fast response to load changes.
Key Features
- Digital display: Shows load in % load, HP, or kW.
- Dual trip relays: Adjustable low and high setpoints for fault protection.
- 4–20 mA output: Integrates with PLC or SCADA systems.
- Compact design: Easy mounting on panels or starter doors.
- Motor support: Range finder toroid for motors up to 50 HP (external CTs for larger motors).