Gehaka G939 User manual

User Manual
Grain moisture meter – model G939
Version: 1.00.000
Date: 08/2013

Summary
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
G939 installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1. Measuring – Moisture measuring . . . . . . . . . . . . . . . . . . . . . .
1.1 Diagram of the functions . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 2. Conguration . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Date and Ttime adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Adjusting the number of elements to be averaged . . . . . . . . . .
2.3 Adjusting the number of decimal digits . . . . . . . . . . . . . . . . . .
2.4 Adjusting the print mode . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.5 Adjusting number of report copies . . . . . . . . . . . . . . . . . . .
2.6 Adjusting the contrast . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.7 Unlocking chamber door . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.8 Uploading Internet equation . . . . . . . . . . . . . . . . . . . . . . . .
2.9 Uploading standard equation . . . . . . . . . . . . . . . . . . . . . . .
2.10 Self-report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.11 Language selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 RS232 Serial Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Thermal printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Error messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5 Extreme conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 3.6 Technical specications . . . . . . . . . . . . . . . . . . . . . . . . .
3.7 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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4I Grain Moisture Meter – Model G939
The G939 moisture meter includes all the characteristics to provide the most accurate
grain moisture reading.
With a simple operation and without operator intervention, model G939 will provide
moisture readings in a few seconds, for a wide variety of products.
With a simple 5-key keypad, the instrument can be easily operated and set up, without
intensive user training.
By applying the “FLOW THRU” technology, G939 provides a fully automatic moisture
analysis. There is no need of previous sample weighing; temperature, density and
weight corrections are performed automatically, without the use of any other resource
or additional tables.
Calibration curves for each cereal have been obtained at Gehaka laboratories, using
samples collected from several areas of the plantation. Using the standard oven method
as a reference, measurement scales for each product were developed. These curves
weretransferredtotheG939memoryandtheyareeasilyidentiedbyproductname
and their version.
If the development of new calibration curves is necessary, there is a function at www.
moisturetester.com.br which allows creating, editing and installing them in your G939
grain moisture meter.
G939 includes three instruments into one,
managed by a state-of-the-art internal
microprocessor. These three instruments
are: One electronic scale, which measures
the sample weight; one built-in digital
thermometer, which measures the sample
temperature inside the chamber and the
G939temperatureandnallyonecapacity
meter, which indicates the moisture
percent, to be later corrected by other
parameters.
Introduction

Grain Moisture Meter – Model G939 I5
Its program performs all the required calculations, thus providing extremely reliable
and repeatable readings. It also performs: automatic setting and checking the proper
operation of all electronic circuits.
The meter’s FLOW THRU design allows the performance of quick measurements, namely,
in less than 15 seconds and without the operator intervention, in a fully automatic way.
Just select the product, pour the sample in the G939 hopper, until a “BEEP” is given,
the G939 will load the sample, perform the measurement and automatically unload the
sample. After a few seconds, you will have the moisture and temperature measurement,
all this shown on an easy to read 16-character / 2-line alphanumeric LCD display, in
Portuguese.
G939 has also a bidirectional RS232C serial communication port. With this, we can
connect the G939 to a printer so the measurement is printed in a label, thus making
the counterchecking easier, or else, we can connect the meter to a PC and transfer the
information to a managing system.
The G939 is operated by a FULL RANGE automatic power source, which means the meter
operation is ensured for 90 – 240 VAC mains, thus protecting the meter from network
voltage variations.
Indication conventions for G939 LCD display:
> Right-hand arrow
< Left-hand arrow
YES Option acknowledgment
ESCAPE Exit

6I Grain Moisture Meter – Model G939
Description
1. SAMPLE LOADING HOPPER
Place where the cereal sample, to
have the moisture measured, will be
weighed.
2. LCD DISPLAY
Displays results and settings with
alphanumeric characters.
3. THERMAL PRINTER (OPTIONAL)
Device for printing measurement
results. Silent, low consumption
operation.
4. DRAWER
Receives the cereal sample from the
chamber, after the measurement
was performed. The meter unloads
automatically.
5. PLASTIC SCOOP
Used for pouring the sample into the
funnel.
6. ON/OFF
Switches ON/OFF the G939 meter.
Operating with numerical setting
multiplies by 10 the indicated value.
7. YES
 Conrms function or setting
selection.
8. RIGHT-HAND ARROW
It displays the next function or
increases the value of one scale
interval.

Grain Moisture Meter – Model G939 I7
9. LEFT-HAND ARROW
Displays the previous function or
decreases the value of one scale interval.
10. ESCAPE (EXIT)
Exits a function or setting that is being
operated at that time. Operating with
numerical setting divides by 10 the
indicated value.
11. POWER CORD CONNECTOR
Place where the power cord will be
connected. G939 operates between 90
and 240 VAC.
12. CARRYING HANDLE
Used for carrying the G939. Caution:
before lifting the G939 remove the drawer,
because due to the tilt it may fall down.
13. RS232 SERIAL PORT CONNECTOR
Data output for printer or PC.
14. HARD LOCK
When connected to RS232 serial output,
it releases access to “Conguration”
function, where G939 congurations will
be made.
Adjusting a value
In addition to the direct functions of the keypad, it can assume other functions, and one
of them is making easier to type a value.
When the setting of a value is selected, the display will show the current value, and to
change it proceed as follows:
KEY FUNCTION
ON/OFF Multiplies the current value by 10;
RIGHT-HAND ARROW Increases the indicated value by one scale interval;
LEFT-HAND ARROW Decreases the indicated value by one scale interval;
ESCAPE (EXIT) Divides by 10 the current value;
YES    Conrmsthecurrentvalueandcompletesthesetting.

8I Grain Moisture Meter – Model G939
Carefully check the packing, if there were marks and damages in the cardboard case,
this means that there were problems during shipment.
Open the packaging, checking the conditions of G939. Remove the equipment and check
whether all its accessories are included.
Place the G939 on a stable table, in order to ensure it will not move during the operation.
Remove the adhesive tapes fastening the drawer and check whether it slides easily.
If the acquired model features a Thermal Printer, install the paper roll as stated in
procedure “3.2 Thermal Printer”.
ConnecttheACcordtotheconnectorontherearpanelandtitsteadily,takingcare
that the plug is fully inserted in the connector. It is not necessary to verify the mains
voltage; the power supply is FULL RANGE, not requiring mains selection. We also do not
recommend the use of voltage stabilizers.
When the cord is plugged in the outlet, G939 will start its operation, performing a self-
diagnosis in order to check whether its components are working properly. If by any
chancethemeterveriesthatsomeofitscomponentsisimproperlyoperating,itwill
indicate an error message on the display regarding the fault.
Leave the G939 meter preheating for 10 minutes. The G939 meter shall operate
continuously plugged in the outlet; use only the ON/OFF key. This way, the equipment
enters the “sleeping” mode and the power consumption is lower than 1 W, however it is
ready to operate.
The G939 meter shall be operated in a place free of excessive dust and with room
temperature between 0º and 40 ºC.
G939 installation

Grain Moisture Meter – Model G939 I9
Te m p. 2 4.8 oC
Sample: 21 >
1. Select“Measuring”fromthemainmenu,depressYEStoconrm;
2. Select the type of cereal you want to measure the moisture. Use Right hand/
LefthandARROWkeysuntilndingthedesiredproduct.Indicationsbelowthe
product names are the moisture minimum and maximum limits the G939 meter
isabletomakethereading.Depress“YES”toconrmyourchoice.
3. Take a sample of at least 200 g of the product you want to measure the moisture
and, using the plastic scoop, slowly pour the cereal sample into the loading
hopper, until the 100% is shown on the display, a beep will be heard indicating the
sample weight is correct. If by any chance the weight is exceeded, the display will
show a value higher than 100%, and the sample excess shall be removed from the
hopper.
4. Within a few seconds, the G939 meter will display the value of product moisture.
If the Right hand/Left hand keys are depressed, the G939 meter will display all the
measurements made, namely:
When selecting Right hand/Left hand Arrow we have:
1. Measuring – Moisture measuring
WHEAT
MOIST.: 13.09%
Sequence number of the measured sample.

10 I Grain Moisture Meter – Model G939
5. After having performed a successful measurement, the G939 meter will send all
measurement data through the serial output to the printer or PC. An example of
report follows:
================================
GEHAKA G939
Fir m w a r e Versio n 0.60.006
Hardware Version 1.00
Serial No. 12345678901234
================================
Current Product..= Wheat
Equation Version.= 20111101
S a m p l e ..........= 2 9
Sample Temp…………..= 24.9 ºC
M e t e r T e m p.......= 2 5.5 ºC
Sample Weight……..= 142.5 g
--------------------------------
M o i s t u r e ........= 1 3.0 5 %
--------------------------------
--------------------------------
Signature 11:02
Responsible person 21/01/13
NOTE: Ifthereisagreattemperaturedierencebetweentheproductand
theG939Hopperwherethetemperaturesensorislocated,themeter
willwaituntilthereisathermalbalancebetweenbothofthem.This
could introduce a delay for the temperature measurement to be
made.This way,we improvethemeterprecision,bymeasuring the
actual sample temperature.
6. When the G939 meter is showing the measurement results on the display and
a new sample is poured into the hopper, the G939 meter will perform a new
measurement,usingthesamecongurationofthepreviousmeasurement.Ifthe
ESCAPE key is depressed, the MEASUREMENT option will be exited, returning to
the MAIN menu.
7. After the measuring cycle, the instrument will unload the sample into the drawer.
NOTE: Ifthemoisturecontentishigherthan22%,theG939meterwillrequest
measuringagainthesamesample,repeatingthemeasurementthree
times in order to ensure a higher reading precision.