Combined power transducer and load monitor for frequency inverter drives
The Unipower APM382 measures true power and monitors two programmable limits on three-phase asymmetric loads supplied at up to 575 V. It operates from a 24 V DC supply and includes internal current ranges up to 80 A. Two independent alarm limits plus a dP/dt function drive digital outputs, while isolated analogue outputs (0/4-20 mA and 0/2-10 V) provide continuous signals. An RS-232 port and digital inputs enable integration and programming via a PC.
Technical Highlights 🔧
- Supply voltage: 24 V DC 10 %.
- Measurement: three-phase asymmetric loads up to 3x600 V; internal current ranges up to 80 A; frequency 10 Hz-1 kHz.
- Analogue outputs: two isolated outputs selectable 0/4-20 mA (max 300 ohm) or 0/2-10 V (min 10 kohm).
- Digital I/O: two digital inputs 12-24 V DC for start functions; two optocoupler outputs 30 V/30 mA for alarm limits.
- Serial communication: RS-232C at 9600 baud for PC setup and data logging.
- Housing: DIN-rail 58 x 102 x 86 mm; IP40 housing, IP20 terminals; weight 300 g.
Benefits ✅
- Ideal for monitoring loads after frequency inverters thanks to wide frequency range and digital scaling.
- Dual alarm limits and dP/dt detection provide comprehensive protection.
- Two analogue outputs and RS-232 enable flexible interfacing and remote parameter setting.
- Galvanic isolation ensures safe integration into control systems.
Applications 🚀
- Monitoring and control of pumps, fans and conveyors driven by variable-frequency drives.
- Industrial energy management requiring accurate kW measurement and scalable analogue signals.
- Automation systems needing dual alarm limits and digital I/O for process control.
The APM382 combines high-accuracy power measurement with programmable alarms, analogue outputs and communication, making it versatile for modern motor control systems.
FAQs
- Q: What is the supply voltage?
A: The APM382 is powered from 24 V DC 10 %.
- Q: How are parameters set?
A: Parameters can be adjusted via front keys or via a PC using the RS-232 port and Unipower software.
- Q: Does it support dP/dt monitoring?
A: Yes. Two independent alarm limits can be configured with start and reaction timers plus a dP/dt detector for rapid load changes.