The hytherograph LB-701 with a control - reading panel LB-725A is designed for air temperature and humidity measurement and regulation in locked places (warehouses, laboratories, climate chambers etc.). It is a stationary device, powered from 230V/50Hz network supply.
The device is composed of two major parts: a hytherograph LB-701 (made in a form of a measurement probe) and a reading - control panel LB-725A. 1m cable connects both parts. There is a possibility of extending the probe’s cable up to 14m.
The measurement probe LB-701 includes: a thin layer temperature sensor Pt-1000, thin layer capacitive relative humidity sensor, electronic processing systems and a system of programmed nonvolatile memory, where all individual probe characteristic are stored as well as identification and technical data. A replaceable casing, which type depends on what the device is used for, protects the measurement probe sensors. The device in a standard version is equipped with a sensor casing (anti pollution filter) type F1.
The reading panel receives signals already processed that include coded information concerning temperature and relative humidity values. It allows on changeable use of different reading panels with the same hytherograph LB-701 without any influence on the measurement results.
The microprocessor from the device's reading panel, basing on the
information from the probe (processed measurement signals and read
calibration characteristics) computes the following values: relative
humidity, temperature, dew point temperature and volume water vapor
content in the air. The temperature and relative humidity values are
presented on an alphanumeric LCD screen at the same time (the size of
numeric characters 25 mm) and can be sent out using an interface. The
lack of switches only increases device's reliability at work and
simplifies its use.
Panel LB-725A control functions allow on controlling four external devices responsible for: humidifying, drying, heating and cooling. Each device can have set limits for switching on and off in the immediate control. When using and external PC computer and an additional program it is possible to cyclically control fluent climate changes (i.e. research climate chambers).
The device is equipped with two series interfaces: voltage RS232C, which allows for it to be attached to any computer system and with a digital current loop for data transmission to long distances. The interfaces allow on remote control and automatic measurement data collection as well as entering the calibration data during the original and secondary calibration.
The panel LB-725A has a real time clock and a measurement results
memory (4000 measurement points) what allows on using it as a
temperature and humidity recorder. The device equipment is composed of
a program for a PC computer used for setting registry parameters and
for memory reading.
The device does not have any mechanic calibration elements (i.e. potentiometers). The device's calibration means sending the calibration data obtained in model climate conditions through a digital interface to device's nonvolatile memory. It guarantees comfort and high calibration accuracy as well as stability of device's meteorological parameters in time.
Hytherograph LB-701 has obtained a certificate of type RP T 95 76 issued by the President of the Central Measurement Office in Warsaw.
Hytherograph LB-701 also has a positive expertise from The Central
Army Meteorology Office in Zielonka (no. 71 dated 05.05.1995),
performed basing on the method of legalizing hygrometers and
The device is produced in a version for temperature measurement only (thermometer LB-701T with a panel LB-725A). Thermometer LB-701T has a measurement converter (in a cylinder case) and an outside temperature sensor Pt1000 (or Pt100) in a standard or special case, adjusted to the individual user requirements (i.e. in a form of a rod from the acid resisting steel, with a special cable). The special casing version allows on measurement of different values in an extended temperature range (-200...+550°C). Thermometer LB-701T can be also purchased separately, as additional equipment for the already had set LB-701/LB-725A. However, in such case it is required that the internal software for the older versions of panel LB-725A is updated. The thermometer LB-701T cable length amounts to: between an outside temperature sensor and a converter - 1..40 m, between a converter and a reading panel - 1..15 m (cable length is defined by a customer).
Methods used for relative humidity and air temperature measurements using hytherographs are introduced in a description.
|Measurement inaccuracy||+/- 0.1°C||+/- 1 last digit|
|Scope of measurement
|-200..+550°C||LB-701T - sensor in a special casing|
|Measurement inaccuracy||+/- 2.0%
+/- 1 last digit
|in the scope of 10...90%,
+/- 1 last digit
|outside of the scope 10...90%|
|Scope of measurement LB-701||10..95%||for temperatures up to +40°C|
|10..60%||for temperatures up to +70°C|
|10..40%||for temperatures up to +80°C|
|Scope of measurement LB-701H||0..100%||for temperatures up to +60°C|
|0..70%||for temperatures up to +70°C|
|0..40%||for temperatures up to +80°C|
|Parameter||Scope of readings||Resolution
|MEASUREMENT READINGS (additionally through a series interface)|
|Parameter||Scope of readings||Resolution
|Dew point temperature
|Volume water vapor content in the air
|Time||months, days, hrs., min||1 min|
|SCOPE OF WORK TEMPERATURES
|Thermometer sensor LB-701T||-60..+90°C||for a standard version|
a special version
|Thermometer converter LB-701T||-40..+85°C|
|RECOMMENDED CONSTANT WORK CONDITIONS *)|
|Scope of temperatures
|Scope of humidity||20..80%|
|Level of environment corrosion aggressiveness accord.
|Degree of casing protection
||IP 60 (limited additionally by the class of filter protection)
||230V AC / 50Hz / 10VA|