Specifications and Product Details:

NA1100DP Online SF6 Gas Moisture Density Monitor

Introduction

NA1100DP SF6 online moisture density monitors are on-line intelligent instruments of the new generation applicable for (extra) high voltage transformers, GIS and other large electrical devices, mainly used for monitoring the moisture in and density of SF6 in electrical equipments. Three physical properties of SF6, moisture, pressure and temperature, are subject to sampling, calculation, estimation, display and uploading, thus the whole online monitoring process is completed.

This monitor mainly comprises (humidity, temperature, pressure) sensors, SCM, OLED display screen and other components. Signals are detected, amplified and sent into the SCM, and then subject to sampling, processing, calculation and display by the SCM. When the measured parameters exceed relevant limit values, the corresponding control system will be activated.

Characteristics

OLED multi-parameter display, clear readings in direct strong light, free of any problem in viewing angles;
Various optional valves applicable for different installation requirements;
Self-calibrating humidity sensors with high stability;
Automatic temperature compensation in a wide range;
Fully sealed, free of leakage, installable both indoor and outdoor;
Intelligent data transmission;
On-line monitoring to reduce gas emissions;
Patented technology, truly reflecting the quality of the gas inside;
Allowed to be completed with multi-functional calibration boxes to ensure easy on-site calibration and repair.

Functions

Display: the OLED display screen features in real-time display of the pressure of SF6 in switches (pressure: 20 °C; same below) and its humidity under standard conditions.
Humidity alarm: when the humidity of SF6 inside switches is higher than the alarm limit, the humidity alarm will flash on the display screen, and the alarm relay will be started in the meanwhile.
Low pressure alarm: when the pressure of SF6 inside switches is lower than the alarm limit, the low pressure alarm will flash on the display screen, and the alarm relay will be started in the meanwhile.
Locking: when the pressure of SF6 inside switches is lower than the locking limit, “locking” will flash on the display screen, and the alarm relay will be started in the meanwhile.
Infrared remote control: the monitor can be operated conveniently and rapidly with a remote control.
Saving: monitoring data can be automatically saved to complete with the software on the host computer, and the saved data can be read.
Data output: the measured data, saved information and the status of the relay can be transmitted to the computer in the main control room through RS485, and the standard Modbus protocol is adopted.
Alarm and self-adjusting threshold values for locking: humidity and low pressure alarms and the threshold values for locking may be determined according to the requirements of users’ equipments.

Technical Indexes

Pressure measuring range:-0.100MPa ~ 0.900MPa (psig)
Pressure measurement accuracy: ≤ ± 0.3% F.S.
Humidity measuring range: 70 ~ 200000ppms
Humidity measurement accuracy: 7.3 ppm + 9.2% (readings)
Alarm threshold: 0.520MPa; 300ppmv (or depending on the requirements of devices)
Locking threshold: 0.500MPa (or depending on the requirements of devices)
Communication interface: RS485 bus
Contact capacity of relays: 3A/250V AC, 3A/30V DC
Voltage of power supply: AC 220V ± 15%