Launched by AOYI in 2012 as the industry's first 3-in-1 Smart Station Monitoring Unit, NSA2 has run for years at a large number of wind and solar plants. It continuously monitors the box-type transformer with telemetry, tele-signalling, remote control, protection and recording, while multiple RS-485 master ports and Ethernet ports connect inverters, smart combiner boxes, meters and environmental monitoring systems at the same time.
Comprehensive smart box transformer monitoring
Continuous online monitoring of box transformer status
Telemetry, tele-signalling, remote control, protection and recording
Clear dynamic display of transformer voltages and currents, giving operators complete automatic remote monitoring
Multi-device communication management
Multiple RS-485 master ports and Ethernet ports
Connect inverters, smart combiner boxes, meters, environmental monitoring systems and more at the same time
NSA2 configuration table
Standard configuration; customizable per project
| Item | NSA2 |
|---|---|
| AC inputs | 3 groups |
| DC analog inputs (PT100 / 4–20 mA) | 6 in total |
| DI (tele-signalling) | 40 |
| DO (remote control) | 10 |
| Item | NSA2 |
|---|---|
| Fiber ports | 2 |
| Ethernet ports | 4 |
| RS-485 ports (master) | 8 |
| Protection | Electrical and non-electrical protection |
| Recording | 500 records |
NSA2 technical specifications
Based on Technical Manual V2.0. Configuration can be customized to project requirements; the contract technical agreement and drawings prevail. Download manuals and protocols ›
AC analog inputs
- Current input
- 5 A or 1 A
- Voltage input
- AC 690V / 400V / 100V
- AC frequency
- 50 Hz or 60 Hz
- Current / voltage accuracy
- Class 0.5
- Frequency accuracy
- ±0.02Hz
- Power / power factor accuracy
- ±1%
Digital inputs / outputs
- Digital inputs
- AC/DC 220 V dry-contact inputs, opto-isolated with surge absorption, insulation withstand ≥ AC 1500 V
- Contact rating
- AC220V 8.0A；AC380V 1.9A；DC250V 1.5A
- Contact life
- > 100,000 operations
Communication
- Fiber ports
- ST connectors, up to 50 km; forms a self-healing fiber ring
- Ethernet ports
- 10/100Base-TX; connects IP cameras, inverter network signals, etc.
- RS-485 master ports
- Connects inverters, smart combiner boxes, multifunction meters, etc.; MODBUS-RTU to IEC 60870-5-103/104 protocol conversion
- Protocols
- MODBUS-RTU、IEC 60870-5-103/104、IEC 61850
- Wireless AP
- Optional, password-protected, range approx. 100 m
Protection and recording
- Non-electrical protection
- Light gas, heavy gas, transformer high / extra-high temperature, low oil level, pressure-relief valve operation, etc.
- Electrical protection
- Overcurrent stages I/II/III, ground fault, overvoltage, undervoltage
- Recording
- 10 pre-/post-fault waveforms, 500 SOE
Power supply
- Supply voltage
- AC/DC 220 V ±20%
- Supply frequency
- 50 Hz, −6% to +2%
- Rated power consumption
- ≤10W
Operating environment
- Operating temperature
- −40℃～+70℃
- Relative humidity
- Max. 90% monthly average RH in the wettest month, non-condensing
- Atmospheric pressure
- 80kPa～110kPa
- Site conditions
- No explosion hazard, conductive dust or corrosive substances
Mounting
- Mounting method
- Flush panel mounting, fixed by four screws on both sides of the front panel
- Device depth
- 225 mm, plus ≥ 80 mm at the rear for wiring
EMC
- Electrostatic discharge immunity
- GB/T 14598.14 (IEC 60255-22-2) Class III
- Oscillatory wave immunity
- GB/T 14598.13 (IEC 60255-22-1) Class III
- Radiated RF electromagnetic field immunity
- GB/T 14598.9 (IEC 60255-22-3) Class III
- Electrical fast transient/burst immunity
- GB/T 14598.10 (IEC 60255-22-4) Class A
- Surge immunity
- GB/T 14598.18 (IEC 60255-22-5) Class III
- Immunity to conducted disturbances induced by RF fields
- GB/T 14598.17 (IEC 60255-22-6) Class III
- Power-frequency immunity
- GB/T 14598.19 (IEC 60255-22-7) Class A
- Conducted and radiated emission limits
- GB/T 14598.16（IEC 60255-25）