Rotronic HygroFlex HF8 User manual

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
Document Type
Page 1of 37
Document title
HygroFlex HF8
Humidity Temperature Transmitter
User Guide
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
Document Type
Page 2of 37
Document title
Table of contents
1Overview ..............................................................................................................................................3
2Dimensional drawings........................................................................................................................4
3General description.............................................................................................................................4
3.1 Power supply options .......................................................................................................................4
3.2 Probe inputs .....................................................................................................................................5
3.3 Measured parameters ......................................................................................................................6
3.4 Calculated psychrometric parameters..............................................................................................6
3.5 Custom Calculations.........................................................................................................................6
3.6 Real time clock.................................................................................................................................7
3.7 Data logging function........................................................................................................................7
3.8 Analog outputs, relay contacts and digital interface options.............................................................7
3.9 Optional display and keypad.............................................................................................................8
3.10 Audible alarm (beeper).....................................................................................................................9
3.11 Service connector.............................................................................................................................9
3.12 Protection grade of models with Ethernet interface..........................................................................9
3.13 HW4 Software compatibility............................................................................................................10
4User configurable settings and functions.......................................................................................10
4.1 Function overview (HF8 and HygroClip 2 probe)............................................................................10
4.2 Interaction between the HF8 and HygroClip 2 probe functions ......................................................11
4.3 Configuration of the analog output signal type ...............................................................................12
5Mechanical installation.....................................................................................................................12
5.1 General guidelines..........................................................................................................................12
5.2 HF8 enclosure................................................................................................................................13
5.3 Installation of the enclosure and probe...........................................................................................13
6Electrical installation ........................................................................................................................14
6.1 General wiring guidelines...............................................................................................................14
6.2 Guidelines for RS-485 wiring..........................................................................................................15
6.3 Cable grip and cable specifications................................................................................................15
6.4 Wiring .............................................................................................................................................15
7Operation ...........................................................................................................................................21
7.1 Analog outputs................................................................................................................................21
7.2 Digital interface...............................................................................................................................21
7.3 Optional display and keypad...........................................................................................................23
7.4 Frequently used settings ................................................................................................................27
7.5 Data logging function......................................................................................................................28
7.6 Relay contacts................................................................................................................................29
7.7 Audible alarm (beeper)...................................................................................................................29
8Maintenance.......................................................................................................................................29
8.1 Service cable..................................................................................................................................29
8.2 Location of the service connector (mini USB type).........................................................................29
8.3 Periodic calibration check of the HygroClip 2 probe.......................................................................30
8.4 HF8 probe calibration and adjustment procedures.........................................................................30
8.5 Cleaning or replacing the probe dust filter......................................................................................32
8.6 Validation of the output signals transmission..................................................................................32
9Firmware updates..............................................................................................................................32
10 Technical data ...................................................................................................................................33
10.1Specifications .................................................................................................................................33
10.2 Dew point accuracy........................................................................................................................35
11 Accessories.......................................................................................................................................35
12 Supporting documents.....................................................................................................................36
13 Document releases ...........................................................................................................................37
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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Page 3of 37
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Applicability:
This manual applies to all instruments of the HygroFlex HF8 series with firmware version 2.x, where 2.x can
be 2.0, 2.1, etc. Changes to the last digit of the version number reflect minor firmware changes that do not
affect the manner in which the instrument should be operated.
Software compatibility warning
The HF8 with firmware version 2.x is designed for use with the ROTRONIC HW4 software version 3.2.0 or
higher. Do not try to configure the HF8 with any version of the ROTRONIC HW4 software lower than
2.4.0 as this will damage the HF8 firmware and prevent normal operation of the transmitter.
1 Overview
The HygroFlex HF8 transmitter series is designed for fixed installation in applications where high
measurement accuracy is required. The HF8 has two probe inputs which can be individually configured for
use with a HygroClip 2 plug-in probe or with a 1-channel analog probe.
The wide assortment of HygroClip 2 humidity-temperature probes can meet almost any application
requirement. The HygroClip 2 probes feature well proven, durable sensors. Digital signal processing within the
probe ensures consistent product performance and also facilitates the task of field maintenance with features
such as potentiometer free – digital calibration, hot-swapping of the probe, etc.
Depending on the HygroClip 2 probe model, the HF8 can measure conditions within the range of 0 to 100
%RH and -100 to 200°C (-148 to 392°F). The HF8 can be configured to calculate a parameter as dew point,
enthalpy, mixing ratio, etc.
The HF8 can be ordered for different types of supply voltage, including DC voltage with galvanic separation
and is available with several combinations of analog output signals (up to 4), digital interface (RS-485,
Ethernet) and relay contacts (up to 4).
Based on the ROTRONIC AirChip 3000 digital technology the HF8 series and HygroClip 2 probes offer the
following user functions:
•User configurable settings
•Calculation of psychrometric parameters such as the dew or frost point
•Custom Calculations (user defined) such as the difference between dew point and temperature
•Humidity temperature calibration and adjustment
•Simulator mode
•Automatic humidity sensor test and drift compensation
•Sensor failure mode
•Data logging
The HF8 has an internal real time clock and can be used to record up to 10,000 pairs of relative humidity and
temperature values provided by a single HygroClip 2 probe or up to 10,000 data values provided by a single
1-channel analog probe. Data logging by the HF8 adds another layer of data protection when the HF8 is
connected to network.
The ability for the user to easily update both the HF8 and HygroClip 2 probe firmware means that instruments
of the HF8 series can be kept up-to-date regarding any future functionality improvement.
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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2 Dimensional drawings
Dimensions in mm
3 General description
3.1 Power supply options
The HF8 can be ordered with different power supply options. Please verify the product identification label to
determine which power supply option is installed on your transmitter.
a) Option 1: 15 to 40 VDC or 12 to 28 VAC – 50/60 Hz, direct connection
With this option, the negative (or ground) side of the analog output signals is tied to the negative side
(VDC) or neutral (VAC) of the power supply .
Depending on the type of output signal, the HF8 will operate with the following minimum voltage
0…1 V outputs: 5 VDC or 5 VAC
0…5 V outputs: 10 VDC or 8 VAC
0…20 mA or 4 …20 mA outputs: 6 VDC or 5 VAC with 0 Ωload
15 VDC or 12 VAC with 500 Ωload
Typical maximum current consumption:
b) Option 2: 9 to 36 VDC or 7 to 24 VAC – 50/60 Hz, galvanically isolated
With this option the HF8 is equipped with an internal power module that provides galvanic isolation
between power and the analog signals. As a result, the negative (or ground) side of the analog output
signals is not tied with the negative side (VDC) or neutral (VAC) of the power supply.
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
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HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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c) Option 3: 85 to 265 VAC, 5 Watt, 50-60 Hz, galvanically isolated
As with option 2, the HF8 is equipped with an internal power module that provides galvanic isolation
between power and the analog signals. As a result, the negative (or ground) side of the analog output
signals is not tied with the negative side (VDC) or neutral (VAC) of the power supply.
d) Option 4: power over a RS-485 network
With the exception of models with any of the galvanically isolated power supply options, the HF8 with RS-
485 interface can be directly powered from the main RS-485 data line. In that case the power terminals of
the HF8 should not be connected.
See Technical Data > Specifications for the typical current consumption of the HF8
3.2 Probe inputs
The HF8 has two probe inputs. Probe input 1 is the input
that is the closest to the front of the transmitter (see
picture)
Using the ROTRONIC HW4 software (Device Manager), each probe input can be configured to accept one of
the following:
oHygroClip 2 humidity-temperature digital probe.
o1-channel analog probe (general): To be compatible with the HF8 the analog probe must meet the
following requirements: supply voltage: max. 5 VDC, current consumption: max. 10 mA, output signal: 0
to max. 3.3 VDC. The HF8 uses a 12-bit A/D converter to digitize the probe analog signal and can be
configured to measure practically any parameter.
oAnalog pressure probe: this is a special case of analog probe and is subject to the same compatibility
requirements. When analog pressure probe is selected, the HF8 automatically uses the signal from the
probe to calculate any humidity parameter that requires barometric pressure as an input value (example:
mixing ratio).
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
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HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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Pin-Out Diagram
3.3 Measured parameters
Depending on the configuration of the probe inputs, the HF8 can measure the following:
oHygroClip 2 probe: humidity and temperature. The HC2 probes measure relative humidity with a
ROTRONIC Hygromer®IN1 capacitive sensor and temperature with a Pt100 RTD.
oAnalog probe (general): any parameter measured by the probe. The parameter unit must be
specified with the HW4 software (Device Manager).
oAnalog pressure probe: the unit used for barometric pressure is set with the HW4 software > Device
Manager > Unit System.
3.4 Calculated psychrometric parameters
When a probe input is configured to accept a HygroClip 2 digital probe, the HF8 can calculate any of the
following parameters based on the humidity and temperature values measured by the probe. To select the
calculated psychrometric parameter, use either the keypad or the HW4 software > Device Manager:
oDew point (Dp) above and below freezing
oFrost point (Fp) below freezing and dew point above freezing
oWet bulb temperature (Tw)
oEnthalpy (H)
oVapor concentration (Dv)
oSpecific humidity (Q)
oMixing ratio by weight (R)
oVapor concentration at saturation (Dvs)
oVapor partial pressure (E)
oVapor saturation pressure (Ew)
Note: calculating some of the above parameters requires barometric pressure as an input parameter. When
no pressure probe is connected to the HF8, a fixed barometric pressure value can be specified using either
the keypad or the ROTRONIC HW4 software.
3.5 Custom Calculations
The ROTRONIC HW4 software version 3.2.0 or higher is required for setting up custom calculations and a
service cable is required to connect the HF8 to a PC running the HW4 software.
The HF8 allows the user to define up to two custom calculations based on measured values such as relative
humidity or on calculated parameters such as the dew point. Custom calculations are constantly updated by
the HF8 and can be shown on the local display and / or displayed on the monitor of a PC running the HW4
software.
1: RXD (UART- digital probe)
2: GND (digital and power)
3: V+: digital pbe: 3.3 VDC nominal, analog pbe: maximum 5.0 VDC, 10 mA
4: AGND (analog ground)
5: Not used
6: 1-channel analog probe signal : + 0.0 to 3.3 VDC
7: TXD (UART – digital probe)
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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A custom calculation can be associated with any of the HF8 inputs. When associated with an input, the
custom calculation can in turn be associated with any of the HF8 analog outputs. The user can also define low
and high limits for a custom calculation and use these limits to generate an alarm and/or energize a relay.
Examples:
oDifference between the humidity measured by probe 1 and probe 2
oDifference between the temperature measured by probe 1 and probe 2
oDifference between temperature measured by probe 1 and the dew or frost point calculated by probe 2
oAverage of the humidity measured by probe 1 and probe 2
oAverage of the temperature measured by probe 1 and probe 2
Instructions regarding custom calculations are provided in the following HW4 manual: E-M-HW4v3-F2-015,
HW4 software version 3: Device Manager – HF8 transmitter.
3.6 Real time clock
The HF8 clock keeps track of the date and time and can be adjusted from the keypad. Using the HW4
software, the clock can be synchronized with the PC date and time. The clock does not automatically adjust
for daylight saving time (DST).
3.7 Data logging function
The HF8 can log up to 10,000 pairs of relative humidity and temperature values provided by a single
HygroClip 2 probe or up to 10,000 data values provided by a single 1-channel analog probe. Both probe
inputs can be logged at the same time and in that case the recording capacity per probe is cut in half. Each
record is automatically date and time stamped. The calculated parameter cannot be recorded.
3.8 Analog outputs, relay contacts and digital interface options
The HF8 can be ordered with any of the following combinations of analog outputs, relay contacts and digital
interface:
o4 analog output signals + 4 relay contacts (no digital interface).
o4 analog output signals + 4 relay contacts + RS-485
o4 analog output signals + 2 relay contacts + RS-485 + Ethernet (wired)
oEthernet with PoE (complies with standard IEEE 802.3af)
Note: models with a RS-485 interface can be powered from a central voltage source (15…40 VDC) via the
RS-485 main data cable. In that case the HF8 should not be powered from any other source.
3.8.1 Analog output signals
All 4 analog outputs of the HF8 provide the same type of signal: 0…20 mA or 4…20 mA or 0…1V or 0…5V or
0…10V. The type of analog signal can be selected globally for all outputs after connecting the HF8 service
connector to a PC running the ROTRONIC HW4 software. No adjustment is required after changing the type
of output signal.
Using the HW4 software, each analog output can be associated with any of the two HF8 probe inputs and can
be made to correspond to one of the following:
oRelative humidity or parameter measured by an analog 1-channel probe
oTemperature
oCalculated parameter, including a Custom Calculation (if enabled)
The scale of each analog output can be set within the numerical limits of -999.99 and 9999.99. The D/A
converters used to generate the analog output signals feature a 16-bit resolution.
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
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HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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3.8.2 RS-485 serial interface
The RS-485 interface can be used to connect together up to 64 devices in a multi-dropped arrangement. In
principle, an unlimited number of such networks can be monitored with the HW4 software, but each RS-485
multi-drop network is limited to 64 devices.
A master device is required to connect a RS-485 network to a PC, such as for example:
oHF8 transmitter with both an Ethernet and a RS-485 port.
oCable AC3010 (master substitute) with USB and RS-485 ports.
RS-485 Compatibility:
The HF8 uses the RO-ASCII communications protocol. This protocol is not compatible with the protocol used
by the previous generation of ROTRONIC instruments and by the HygroLog HL-NT data logger. Do not
connect legacy products or the HL-NT data logger to the same RS-485 multi-drop network as the HF8
transmitter.
3.8.3 Relay contacts
The HF8 is available with up to 4 relay contacts (SPDT: single pole double throw). Connection to a PC running
the ROTRONIC HW4 software is required to configure each relay contact.
Each relay contact can be associated with any of the two HF8 probe inputs and can be made to monitor alarm
conditions associated with one of the following:
oRelative humidity or parameter measured by an analog 1-channel probe
oTemperature
oCalculated parameter, including a Custom Calculation (if enabled)
A relay output is energized when the value of the parameter being monitored corresponds to a user defined
out-of-limits value. High and low limits for the measured and calculated parameters can be defined for each
individual probe input with the HW4 software Device Manager (see E-M-HW4v3-F2-015).
The HW4 software is also used to configure the operating parameters of each relay such as time delay to
energize or de-energize the relay, latching or non-latching operation and can also be used to limit operation of
the relays to a time schedule.
3.9 Optional display and keypad
The optional LC display option of the HF8 has a backlight which can be set
to be either permanently on, or to be on for a few seconds when a key is
pressed on the keypad. The backlight can also be disabled.
The display shows data from one probe at a time. When both probe inputs
of the HF8 are being used, the difference between the two probes can also
be displayed (Delta Probe).
The data from one probe or the difference between two probes or up to two
user defined Custom Calculations can be shown on the display. Selection
of the displayed data is done from the keypad (+ or – key).
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
Document code Unit
HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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Standard
3-line
Large
o%RH
oTemperature
oDate and time
oProbe number
o%RH
oTemperature
oCalculated parameter
oProbe number
The date and time are not shown
o%RH or temperature or
calculated parameter shown
in large characters
oDate and time
oProbe number
Both the parameter and probe
can be changed from the keypad
The display can be configured to show a trend indicator on each line:
▲: increasing value
▼: decreasing value
Both arrows are displayed when the value is stable.
3.9.1 Alarm Indication on the display
Depending on the type of alarm, the display shows either the symbol [ ! ] to the right of the value or a text at
the bottom of the display when the HF8 detects an alarm condition:
oOut-of-limits value (defined with the ROTRONIC HW4 software for each probe input, includes
measured values and calculated parameter).
oNo communication with the probe.
oDisplay of fixed values when no probe is connected the input. Easily identified humidity and
temperature values can be specified with the HW4 software for each probe input.
oBad RH sensor or major sensor failure (open or shorted sensor – humidity and temperature)
3.10 Audible alarm (beeper)
The HF8 can emit a sound when an alarm condition occurs (out-of-limit value, loss of communication with a
probe, etc.). The audible alarm can be disabled, enabled and configured after connecting the HF8 service
connector to a PC running the ROTRONIC HW4 software. For details, see the following HW4 manual:
E-M-HW4v3-F2-015. The HF8 optional display and keypad do not provide access to the audible alarm
function.
3.11 Service connector
The service connector is a UART digital interface (Universal Asynchronous Receiver Transmitter) with a mini-
USB type connector. This allows connecting the HF8 with a service cable to a PC running the ROTRONIC
HW4 software. See “Maintenance” for the location of the service connector and for the type of service cable to
be used. The service connector is used for the following:
oConfiguration of the HF8
oDownloading data recorded on the HF8
oAccess to the HygroClip 2 probe functions
oFirmware updates
Note: the optional digital interface (Ethernet or RS-485) offers the same functionality as the service connector.
3.12 Protection grade of models with Ethernet interface
The protection grade of the enclosure of models with an Ethernet interface is not rated IP65 / NEMA 4.
© 2012-2013; Rotronic AG E-M-HF8-V2_20

E-M-HF8-V2_13 Rotronic AG
Bassersdorf, Switzerland
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HygroFlex HF8 Humidity Temperature
Transmitter: User Guide Instruction Manual
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3.13 HW4 Software compatibility
The HF8 is best used with HW4 version 3.2.0 or higher.
WARNING: do not use the HF8 with any HW4 version lower than 2.4.0 as this could damage the HF8
firmware and prevent normal operation.
4 User configurable settings and functions
The HF8 can be used just as any conventional humidity and temperature transmitter. Making use of the HF8
configurable settings and functions is entirely up to the user and the appropriate settings depend on the user
application. We have provided below a short description of the HF8 functions and also indicated the factory
default settings.
4.1 Function overview (HF8 and HygroClip 2 probe)
MEASUREMENT ACCURACY AND RELIABILITY
Function
Description
►Humidity / temperature adjustment
o1-point or multi-point humidity calibration or adjustment
o1-point or 2-point temperature calibration or adjustment
oGenerate a time stamp for calibrations and adjustments
oRetain and view last adjustment date and adjustment values
oGenerate calibration and adjustment protocols
►Automatic humidity sensor test
and optional drift compensation
Tests the humidity sensor for drift caused by contaminants and
can be used to automatically apply a correction. The test is
automatically carried out at regular intervals of time. Can be
configured, enabled, or disabled
The humidity sensor status can be verified either with the HW4
software or with the instrument display (if available) and is
shown as Good, SQ-tuned (corrected for drift) or Bad (defective)
►Data recording by the probe
The data recording function differs from a true data logging
function in the sense that the HygroClip 2 probe does not time
stamp the data. The data recording function can be use to
investigate events such as a sensor malfunction as well as to
retrieve data that would otherwise be lost
oStart or stop data recording - up to 2000 value pairs (%RH
and temperature). Starting a recording session erases all
previously recorded data
oThe recording mode and log interval can be specified
oWhen the device is powered off, the recording session is
paused but not ended As long as the recording session has
not been ended, the device automatically resumes recording
data when powered up again
oThe recorded data can be downloaded to a PC with the
HW4 software, time stamped and viewed
►Data logging by the HF8
The HF8 can log up to 10,000 pairs of relative humidity and
temperature values provided by a single HygroClip 2 probe or
up to 10,000 data values provided by a single 1-channel analog
probe. Both probe inputs can be logged at the same time and in
that case the recording capacity per probe is cut in half. Each
record is automatically date and time stamped. The calculated
parameter cannot be recorded.
© 2012-2013; Rotronic AG E-M-HF8-V2_20