Delta OHM HD45 Series User manual

HD45 - 1 - Quick guide
HD45 series Quick guide – ENGLISH
HD45 series instruments consist of transmitters, indicators and regulators suitable for measuring
and controlling, depending on model, the following environmental parameters:
•Relative humidity (RH)
•Ambient temperature (T)
•Carbon dioxide (CO2)
•Dewpoint Temperature (Td, computed value)
They are wall-mounted and have built-in sensors. Instruments are factory calibrated and do not
require additional intervention from the user. Power supply: 24Vac or 15…35Vdc.
HD45… (HD45 BVR and HD45BAR excluded) HD45 BVR and HD45 BAR
•“POWER” LED: indicates the power supply state. In models without display, it blinks when
errors occur.
•LCD Display: it simultaneously shows all values measured by the instrument.
•LED level indicators: they show the air quality level (in HD45 BVR and HD45 BAR only).
•Serial output with mini-USB connector: it allows the connection to a PC for the instrument
configuration. Connection is obtained via the RS45 (not isolated) or RS45I (isolated) special
cable, which has a mini-USB connector to the instrument end, and a USB connector to the
computer end. The special cable has a built-in USB adaptor. With the RS45 cable, the instrument
is directly powered through the computer USB port. Attention: do not use standard mini-USB/USB
adaptor cable.
INSTALLATION AND CONNECTION
“POWER
”
LED
LCD
Serial output with
mini-USB connector
“Air quality”
LED indicators
solo
HD45…D
Open the housing by pushing the
upper and lower tabs, then pull to
remove the front panel.
Serial output with
mini-USB connector

HD45 - 2 - Quick guide
Install the instrument at about 1.5m height above the floor and at least 1m distance from the
corners. Do not mount it near windows, outside doors, direct heat, air conditioning or within
occupants’ breathing zone.
CONNECTION DIAGRAMS
OPERATING MODE
Supply the instrument with the correct voltage. A wrong power supply may cause permanent
damage to the instrument. “POWER” LED activation indicates that the instrument is being
powered. About 15 minutes are needed to ensure stable measures and indicated accuracy.
In models provided with a display, measures are shown after a few seconds. The instruments
simultaneously display all measured values.
The instruments are factory preset to be immediately operative. Users can customize instrument
configuration by connecting the serial port located on the instrument side to a computer via the
RS45 or RS45I cable and with the help of the supplied DeltaLog14 program. The computer can be
connected even if the instrument has been already installed and powered. For the connection to
work properly, installation of the USB drivers included in the supplied CD-ROM is required.
ANALOG OUTPUTS
HD45…V… and HD45…A… models have an analog output (0…10V or 4…20mA) for each quantity
measured by the instrument. The default correspondence between analog output and measuring
range is as follows:
Temperature output Humidity output CO2 output
0V or 4mA = -20.0 °C 0V or 4mA = 0.0 % 0V or 4mA = 0
10V or 20mA = 80.0 °C 10V or 20mA = 100.0 % 10V or 20mA = 5000 ppm
Each output can be configured to correspond to a different measuring range interval.
In case of measure out of the set interval, the analog output remains fixed to the extreme
value if the measure is just a little out, and it becomes 11Vdc or 22mA if the measures is
too over or under-range. For a correct operation, please follow the load resistance
specifications for the analog outputs indicated in the technical data.
Fix the base to a wall, with
connectors at the bottom
and the slot matching the
connection cable output.
Proceed with connections.
Replace the front panel inserting
the upper and lower tabs in
their respective slots .

HD45 - 3 - Quick guide
RELAY OUTPUTS
HD45…R models have one relay output, that can be associated to one of the quantities measured
by the instrument. The potential free contact output is preset to close when the measurement
value exceeds the threshold limit, and to open when the measurement value falls below the
threshold limit minus the hysteresis. The relay is bistable type: in case of no power supply, the
relay contact holds its last position.
Thresholds and hysteresis can be configured. The relay can be configured to operate with one or two
thresholds. The relay contact can also be set to close when a measurement error occurs, for
example in case of a sensor fault or of an over range measure.
In HD45 17…R and HD45 7B…R models, the relay is factory associated with temperature,
whereas in HD45 B…R models, it is factory associated with CO2 measurement.
The relay can be used in two modes:
• Simplified mode: the relay functions with a single threshold, that can be selected from a series of
fixed values via a rotary switch.
• Complete mode: the relay may function with one or two thresholds custom-settable via a PC.
Toggling between the two modes is made by means of a rotary switch placed on the instrument
electric board, between the terminal board and the mini-USB connector.
If switch is in position 0 (default setting), the instrument is in complete mode and operates with
thresholds and hysteresis set via software, which has the following default settings:
Temperature (HD45 17…R and HD45 7B…R) CO2(HD45 B…R)
Threshold = 100.0 °C Threshold = 1000 ppm
Hysteresis = 5.0 °C Hysteresis = 100 ppm
If switch is in a position other than zero, the instrument is in simplified mode: the relay activates
only on the threshold set with the rotary switch. Depending if the relay is associated with CO2 or
temperature measurement, each switch position corresponds to a threshold according to table
below: POSITION CO2THRESHOLD (ppm) TEMPERATURE THRESHOLD (°C)
0 Rotary switch disabled Rotary switch disabled
1 600 18.0
2 800 23.0
3 900 28.0
4 1000 33.0
5 1200 38.0
6 1400 43.0
7 1600 48.0
8 1800 53.0
9 2000 58.0
If switch is in a position other than zero, hysteresis is preset to 100 ppm for the CO2 measurement
and to 5.0°C for temperature. Hysteresis and activation mode can be changed via PC connection.
For temperature, threshold 1 value and the fixed interval between succeeding positions can be
changed.
The relay can be associated with humidity, and threshold 1 value along with switch fixed interval can
be specified.
Mini-USB connector
Rotary switch with 10 positions
numbered from 0 to 9
Terminal board

HD45 - 4 - Quick guide
LED INDICATORS IN HD45 BVR AND HD45 BAR MODELS
HD45 BVR and HD45 BAR models are supplied with four LEDs showing the air quality level.
Switching from one level to another is determined by the values of three thresholds, preset to 600,
800 and 1400 ppm.
Optimal: It is on the green LED CO2< Lower threshold (600 ppm)
Satisfying: It is on the green LED CO2> Lower threshold (600 ppm)
CO2< Medium threshold (800 ppm)
Mediocre: It is on the yellow LED CO2> Medium threshold (800 ppm)
CO2< Upper threshold (1400 ppm)
Poor: It is on the red LED CO2> Upper threshold (1400 ppm)
RS485 CONNECTION
HD45…S… models are supplied with a RS485 serial output with MODBUS-RTU protocol. Up to 247
instruments can be connected on the network through a shielded cable with twisted pairs for signals
and a third wire for common.
Line terminations shall be located at the two ends of the network. Polarization resistors are
connected between signal and power supply lines, in a single point of the line. The cable shield must
be connected at both line ends. Data line shall be kept separated from any power lines.
If more than 32 devices have to be connected (31 instruments plus the Master unit), place a signal
repeater between a group and the next one, with a line termination connected at both ends of each
group.
Each device has its own address. There shall not be more devices with the same address.
The preset communication parameters are as follows: Baud rate: 19200
Parity: Even
Start bit: 1
Data bits: 8
Stop bits: 1
RS485 communication is disabled if the instrument is connected to a PC via mini-USB output.
This quick guide explains in brief the installation steps and operating modes of the instrument. For a detailed explanation and
an optimal use of all the instrument functions, please refer to the complete instruction manual. For instrument configuration
through a computer, please refer to the software manual.
Rev 2.0 –18/10/2010
RS232C / RS485
or
USB / RS485
converter
Line
termination
Line
termination