LSI LASTEM EXP815.1 Relative Humidity and Air Temperature
Frequently Asked Questions
Q: How often should I calibrate the Thermohygrometer?
A: It is recommended to calibrate the Thermohygrometer annually for accurate measurements.
Q: Can the sensor be used outdoors?
A: The sensor is designed for indoor use; outdoor usage may affect its performance.
Installation
- Choose a suitable location for the sensor ensuring it is exposed to the air to be measured.
- Install the sensor in small spaces, pipes, or ducts as required.
- For dirty air applications, consider using the DYA225 shelter to protect the sensor from dirt accumulation.
Usage
- Connect the appropriate output (analog, digital, or radio) based on your monitoring system requirements.
- Ensure the cable length does not exceed 100 meters for optimal performance.
- Monitor and record the air temperature and relative humidity readings as needed.
Maintenance
- Regularly check and clean the sensor to ensure accurate readings.
- Replace the battery (AA 3.6 V) as needed to maintain power supply.
Thermohygrometer (analogue, digital and radio outputs )
- 4…20 mA, RS485-Modbus RTU and Radio outputs version
- Easy installation of the sensitive part, even in small spaces or pipes
- Cable length from 5 to 100 m
- Dew Point calculation and output (replace RH% output)
- Simple replacement of the sensitive element
- Outstanding accuracy (1.5%) for RH%
Sensor for measuring the air temperature and relative humidity in indoor environments or inside pipes or ducts. In applications with dirty air, it is possible to mount the sensor inside the DYA225 shelter in order to prevent dirt from accumulating directly on the sensitive element.
Technical Specifications
PN | EXP815.1 | DMA975.1 | DMA875.1 |
Measurements | °C/RH% | °C/RH% | °C/RH% |
Output | Radio | RS485 | 2×0/4…20 mA |
Frequency | 868 MHz | – | – |
Radio transmission power | 25 ± 3 mW | – | – |
Radio transmission distance (line-of-sight) | 600 m | – | – |
Transmission rate | 10’ | – | – |
Battery life | >2 years | – | – |
Protocol | – | Modbus RTU®, TTY-ASCII | – |
Configuration | – | Hyperterminal | – |
RS485 protection | – | Galvanic insulation
(3 kV, UL1577) |
– |
RS485 speed | – | 1200…115 kbps | – |
PN | EXP815.1 | DMA975.1 | DMA875.1 |
Power supply | Battery (AA 3.6 V) | 10…30 V AC/DC | 10…30 V AC/DC |
Power consumption | <10 µW stand-by 120 mW in trasmissione | 1 W | 1 W |
Electric protections | NO (electrically insulated system) | Tranzorb and Emifilter | Tranzorb and Emifilter |
Common Technical Specifications
Temperature | Principle | RTD Pt100 1/3 DIN B (Class AA EN60751) |
Measuring range | Programmable: -40…60 °C, -50…60 °C, -50…70 °C, -30…100 °C | |
Accuracy | 0.1 °C (@ 0 °C) | |
Resolution | 0.01 °C | |
Response time (T90) | Typical 4 s (1 m/sec air flow) | |
Long term stability | <0.1 °C / year | |
Relative Humidity | Principle | Capacitive |
Measuring range | 0…100% | |
Accuracy | ±1% (@5…95%) | |
Output | Programmable: RH% or Dew Point | |
Long term stability | <±1% / year | |
Response time (T90) | Typical 10 s (1m/s air flow) | |
Hysteresis | <1% | |
Resolution | 0.1% | |
General Information | Protection rate | IP65 |
Operative temperature | -50…100 °C |
Accessories
LSI LASTEM Srl Via Ex SP. 161 Dosso, 9 20049 Settala (MI) Italy
Tel. +39 02 954141
Fax +39 02 95770594
Email info@lsi-lastem.com
www.lsi-lastem.com
Documents / Resources
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LSI LASTEM EXP815.1 Relative Humidity and Air Temperature [pdf] Owner's Manual EXP815.1, EXP815.1 Relative Humidity and Air Temperature, Relative Humidity and Air Temperature, Humidity and Air Temperature, Air Temperature, Temperature |