Filters Residual Life Indication
Today most filters are still replaced by scheduled maintenance, since no viable RLI sensor is yet available. Some filtration systems, like inside HVACs, may employ Differential Pressure Sensors which provide an indirect measurement of a filter approaching saturation. However these have major shortcomings, a cumbersome mechanical installation since they need a by-pass to the main fluid path, which makes them expensive and unusable for mission critical safety applications. Use of Differential Pressure Sensors is relegated to particle filters since they cannot be applied to vapor filtration, such activated carbon or silica filters.
SENSIPLUS provides a low cost, miniature RLI to all material based filters. Our product can be applied universally to HEPA, Fiber, Paper and Active Carbon or Silica Filters for Oil, Air, Gasoline and Water filtration.
It is an highly accurate, temperature compensated direct measurement of the impedance spectra of the filter as an indications of its saturation.
Specifications
| ELECTRICAL | |
| Supply Voltage | 1.5-3.6V |
| Max Current | 0.4mA continuous when reading filter with EIS |
| Size | 3x3mm, 0.8mm thickness |
| Interface | I2C or SENSIBUS, single data wire multidrop sensor array cable interface, 1.5-3.6V |
| Unique Identifier | OTP 48bits Unique Device Identifier, 16bits User Defined |
| ELECTRICAL IMPEDANCE SPECTROSCOPY | |
| Frequency | 3.1mHz to 1.2MHz |
| Vpp output sinewave | 156mV to 2.8Vpp |
| Coherent demodulation | 1st, 2nd or 3rd harmonic |
| Output | Reciprocal of real or imagery component |
| Wide Measurement Range | From ohms to 100MΩ for different filter sizes |
| TEMPERATURE | |
| Range | -40°C to 125°C |
| Accuracy | ±0.1°C |
Applications
- All types of carbon and activated carbon filters
- All types of paper, nylon, fiberglass, polyester, rubber, polypropylene, oil impregnated HEPA filters
- Medium independent, air, water, oil, gasoline.
