ROTRONIC HF7 - Manual (Page 9)

E-M-HF7-V1_24
Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF7 Humidity Temperature
Transmitters: User Guide Instruction Manual
Document Type
Page 9 of 23
Document title
© 2009-2011; Rotronic AG E-M-HF7-V1_24
Humidity / temperature adjustment HF72, HF73
Device write protection HF72, HF73 Disabled
Menu access from keypad HF72, HF73 Enabled
Limit humidity output to 100 %RH HF72, HF73 Enabled
Out-of-limit value digital / display alarm HF72, HF73 Disabled
Data recording HF72, HF73 Enabled (loop mode – 10 min. interval)
Automatic humidity sensor test HF72, HF73 Disabled
Humidity sensor drift compensation HF72, HF73 Disabled
Fail safe mode HF72, HF73 Disabled
Simulator mode HF72, HF73 Disabled
o
For a detailed description of all AirChip 3000 / HF7 main functions see document E-T-AC3000-DF-V1
o Instructions regarding the configuration of the HF7 and access to its functions are provided in the
following manuals:
E-M-HW4v3-Main
E-M-HW4v3-F2-007
E-M-HW4v3-DR-001
E-M-HW4v3-A2-001
o The factory default setting for dew / frost point calculation is frost point below freezing
5 Mechanical installation
5.1 General guidelines
Relative humidity is extremely dependent on temperature. Proper measurement of relative humidity requires
that the probe and its sensors be at exactly the temperature of the environment to be measured. Because of
this, the location where you choose to install the probe can have a significant effect on the performance of the
instrument. The following guidelines should guarantee good instrument performance:
a) Select a representative location: install the probe where humidity, temperature and pressure
conditions are representative of the environment to be measured.
b) Provide good air movement at the probe: air velocity of at least 200 ft/ minute (1 meter/second)
facilitates adaptation of the probe to changing temperature.
c) Avoid the following: (1) Close proximity of the probe to a heating element, a cooling coil, a cold or
hot wall, direct exposure to sun rays, etc. (2) Close proximity of the probe to a steam injector,
humidifier, direct exposure to precipitation, etc. (3) Unstable pressure conditions resulting from
excessive air turbulence.
d) Immerse as much of the probe as possible in the environment to be measured.
HF7 type N with 120 mm probe length: to avoid measurement errors caused by temperature
gradients fully immerse the probe barrel in the environment to be measured