Delta OHM DO 9721 User manual

DO 9721
INSTRUCTIONS MANUAL

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DO 9721

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DO 9721
QUANTUM-PHOTO RADIOMETER AND THERMOMETER
DATA-LOGGER
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1Input A, DIN 45326 8-pole connector.
2HOLD symbol, the measurement refers to the moment in which the HOLD key was pressed.
3Battery symbol: flashes during RECORD function, permanently lit if the battery is running low
4REL symbol, indicates that the instrument is making a relative measurement.
5Serial Out/Memory. Fixed symbol: the instrument is storing. Flashing symbol: serial output is
enabled.
6MED symbol: the display shows the mean values found during RCD function.
7Q: instrument in Q-energy function, flashes when it has reached the limit.
8Time: the display indicates the integration time, if flashing it has reached the time programmed
for integration.
9Lux: the led indicates that the measurement is in lux.
10 µW/cm2: the led indicates that the measurement is in µW/cm2.
11 µmol/m2s: the led indicates that the measurement is in µmol m–2 s–1.
12 REL key: shows the difference between the current value and the value stored when the REL
key is pressed.
13 HOLD key for blocking the reading.
14 Unit A key: for selecting the measurement unit for input A, depending on the probe fitted. When
turned to P0 mode, it sets the Q-energy and Time limits for input A.
15 Serial Output: activates data transmission at the RS232C serial output.
16 s (Memory clear): increases the parameters in programming mode; when held down it erases
the “RCD” memory; when pressed with P1, it erases the permanent memory.
17 PROG key: activates the programs P0... P1... P... of the different instrument functions.
18 Connector for RS232C (SUB D male 9 pole).
19 Input B, DIN 45326 8-pole connector.
20 Symbol 103: indicates multiplication factor 103for the respective channel .
21 Symbols A and B: for magnitudes Q and T indicate the channel selected.
22 A-B: the bottom display shows the difference between A and B. The top display shows A.
23 MIN symbol: the display shows the minimum values found during RCD function.
24 MAX symbol: the display shows the maximum values found during RCD function.
25 °C: the led indicates that the temperature measurement is in degrees Centigrade.
26 °F: the led indicates that the temperature measurement is in degrees Fahrenheit.
27 fcd: the led indicates that the measurement is in fcd (foot-candle).
28 W/m2: the led indicates that the measurement is in W/m2.
29 cd/m2: the led indicates that the measurement is in cd/m2.
30 On/Off key: for switching the instrument on or off.
31 Unit B key: for selecting the measurement unit for input B, depending on the probe fitted. When
turned to P0 mode, it sets the Q-energy and Time limits for input B.
32 A-B key: shows the difference between the inputs.
33 Data Call key (Max - Min - Med - Q - Time): recalls on the display the maximum, mean, mini-
mum, Q and Time values of each input.
34 t (RCD): starts and stops the RECORD function, in programming mode it decreases the para-
meter shown.
35 ENTER key: starts and stops storage, confirms the parameters set during programming.
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INTRODUCTION
The DELTA OHM DO 9721 quantum photo-radiometer and thermometer data logger has been
designed for measuring illuminance, radiance, luminance and temperature.
The instrument has two inputs, A and B, and automatically recognises the probes connected,
whether they be illuminance, radiance, luminance or temperature probes, and can display the diffe-
rence between the two inputs.
As the probes are interchangeable, it is possible to choose the most suitable combination for all
applications without having to recalibrate the instrument. The DO 9721 is able to take illuminance
measurements in lux and in fcd (foot-candle), irradiance measurements in W/m2, in µW/cm2e in
µmol/m2s, luminance measurements in cd/m2and temperature measurements in °C or °F.
The instrument’s Data Logger function enables it to store up to 30,000 readings. The sampling
period is variable from 1 second to 12 hours.
The data acquired may later be transferred to a Personal Computer or a printer by means of the
opto-insulated serial line RS232C. For each value stored the date and time of acquisition are indi-
cated; each acquisition block is ended with a report which provides the maximum, minimum and
mean values.
With the Serial Output function it is possible to obtain the instantaneous values measured by the
instrument at the output of the serial line RS232C, in order to send them to a printer or a computer.
Other functions such as Hold (which blocks the display), Rel (for taking relative measurements),
Record (for storing the maximum, minimum and mean values) and Q (integration in time of the
measurements with alarm threshold) further enrich the instrument’s performance.
Thanks to its versatility and to its storage capacity, the instrument is suitable for a wide variety of
applications, both in the field and in the laboratory.
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ON/OFF
HOLD + ON/OFF
HOLD
ON/OFF key. Press this key
repeatedly to switch the instru-
ment on or off.
The instrument has a cut-out
system (Auto Power Off) which
switches off automatically after
about 8 minutes.
HOLD and ON/OFF key. If this
key is pressed and held down
together with the ON/OFF key
while switching on, for the dura-
tion of the switching-on routine,
the self cut-out function (Auto
Power Off) is disactivated.
The battery symbol flashes at a
frequency of 1 Hz.
The instrument can be switched
off only by pressing the ON/OFF
key.
When this key is pressed during
normal operation the value shown
on the display is frozen and the
HOLD symbol lights up. Updating
of the internal data continues.
When the key is pressed for the
second time the instrument
returns to normal operation and
the HOLD symbol goes off.
All the symbols are lit for a few
seconds after pressing the
ON/OFF key.
Complete display.
The H symbol flashes to indicate
that Auto Power Off is disabled.
KEY SIMBOLS LIT BESIDES
THE NUMBERS FUNCTION DESCRIPTION
KEYBOARD DESCRIPTION
+

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REL
UNIT A
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KEY SIMBOLS LIT BESIDES
THE NUMBERS FUNCTION DESCRIPTION
The REL key allows you to
display or store relative values or
send them immediately onto the
serial line. The values for compa-
rison are stored at the precise
moment in which the key is pres-
sed. Data may be stored when
the REL button is active.
After data has been sent onto the
serial line, in immediate or remote
mode from the instrument’s inter-
nal memory, obtained with the
REL function active, a report will
be provided giving the maximum,
minimum and mean relative
values and the reference values
on which the calculation of the
relative values was based.
When the Unit A key is pressed, it
selects the measurement unit in
which the magnitude measured
by the probe connected to input A
is presented at the top of the
display. Depending on the type of
probe connected, the following
units are enabled: °C or °F; lux or
fcd; W/m2or µW/cm2; µmol/m2s;
cd/m2.
This key also gives access to the
Q and Time functions. The led
corresponding to the unit chosen
lights up.
When pressed after the PROG
key, in P0 function, the key gives
access to the programming of the
limits for the integration value Q
and for the Time; see the specific
section.
REL
10
3
10
3

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UNIT B
A-B
SERIAL OUTPUT
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KEY SIMBOLS LIT BESIDES
THE NUMBERS FUNCTION DESCRIPTION
For channel B, this fulfils a similar
function to unit A; it is presented
at the bottom of the display.
Pressing A-B obtains, at the bot-
tom of the display, the difference
between the value at input A and
the one at input B.
The measurement unit selected
for the two values must be the
same for both probes, otherwise
an ERR message is given.
The Serial Output key enables the
data being acquired to be sent
immediately onto the serial line.
The Serial Out symbol flashes.
Note:
The choice of the baud rate
influences the speed at which the
data are sent as shown in the
table:
Serial
Out
Memory
10
3
10
3
BAUD
RATE
300 Baud
600 Baud
> 600 Baud
MÍNIMUM
SENDING
INTERVAL
4 sec.
2 sec.
1 sec.

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P0+
P0+ or
P1+ = data dump
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KEY SIMBOLS LIT BESIDES
THE NUMBERS FUNCTION DESCRIPTION
- P0 -
When ENTER is pressed with P0
on the display, the instrument
returns to normal operating mode
without storing any parameter.
Press the PROG key to move on
to step P1.
When unit A or unit B is pressed
with P0 on the display, it gives
access to the function for pro-
gramming the integration or time
limits for the probe Q and T func-
tions. For details, see the specific
chapter.
- P1 -
When ENTER is pressed with P1
on the display, the data stored in
the memory of the instrument are
unloaded (DUMP); press the
PROG key to move on to step P2.
During data dumping the messa-
ge P1 appears on the upper
display.

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84
KEY SIMBOLS LIT BESIDES
THE NUMBERS FUNCTION DESCRIPTION
At the end the instrument automa-
tically returns to normal operating
mode.
The unloading of data from the
instrument memory may be
momentarily stopped by pressing
the ENTER key. Press the
ENTER key again to reactivate
data unloading.
When the PROG key is pressed,
data unloading is finally conclu-
ded. After a few seconds the
instrument display returns to nor-
mal mode.
At the end of each block the
report is sent with the maximum,
minimum and mean values calcu-
lated on the block.
During the “DUMP” phase the
instrument does not switch off
automatically, all the key functions
are disabled except the ENTER,
PROG and ON/OFF keys.
Note:
The block is defined at the
moment of storage as a group of
consecutive recordings. The first
interruption of storage ends and
determines the block.