Description
VanGuard PSMU-350-3
Technical Specifications
- Product type: DC power monitoring unit
- Input: DC voltage, current, insulation
- Output: Alarm relay contacts
- Communication: RS485 Modbus
- Supply: DC220 V / 110 V
- Accuracy: 0.5 class
- Operating temperature: -10 °C to +55 °C
- Storage temperature: -25 °C to +70 °C
- Humidity: 5 % to 95 %, non-condensing
- Protection: IP20
- Installation: Panel / DIN rail
- Display: LED/LCD
Functional Features
- DC bus voltage monitoring
- Charger current measurement
- DC system insulation monitoring
- Over-voltage and under-voltage alarm
- Insulation low alarm
- RS485 background communication
- Alarm relay output
- Front panel display
- Event logging
- Power industry standard
Application Scenarios
- Substation DC panel monitoring
- Plant DC operating power
- Substation battery monitoring
- DC system insulation monitoring
- Power operating power alarm
Materials and Construction
- Housing: Engineering plastic
- PCB: FR4
- Sensors: DC Hall
- Terminals: Screw terminals
- Display: LED/LCD
- Seal: Panel gasket
Structural Features
- Panel/DIN rail square housing
- Front panel display and pushbuttons
- Rear voltage/current, communication, alarm terminals
- Internal sampling, computation, output
- Fanless cooling
- Removable terminals
Working Principle DC bus voltage is divided and sampled; current is sensed by Hall sensor; insulation monitoring circuit injects low-frequency signal to compute ground insulation resistance. The CPU computes values; on limit violation the alarm relay operates. RS485 uploads to background.
Installation Requirements
- Panel or DIN rail mount
- Connect DC bus voltage
- Battery current CT
- Shielded RS485
- Grounding
- Temperature -10 °C to +55 °C
- Set bus voltage after power-up
- Configure communication address
Precautions
- DC polarity correct
- Current direction correct
- RS485 120 Ω termination
- Set alarm values per system
- Store spares in dry environment
- Periodically calibrate sampling
