PCE Health and Fitness PCE-A-315 User manual

PCE Americas Inc.
711 Commerce Way
Suite 8
Jupiter
FL-33458
USA
From outside US: +1
Tel: [phone]
Fax: [phone]
[email protected]
www.pce-instruments.com/english
www.pce-instruments.com
PCE Instruments UK Ltd.
Unit 11
Southpoint Business Park
Ensign way
Hampshire / Southampton
United Kingdom, SO31 4RF
From outside UK: +44
Tel: [phone]
Fax: [phone]
[email protected]
Grain Moisture Analyzer
PCE-A-315
INSTRUCTION MANUAL

Contents
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Contents
GENERAL SAFETY RECOMMENDATIONS .............................................................. 3
1. GENERAL INFORMATION ..................................................................................... 4
2. SPECIFICATIONS................................................................................................... 6
3. PRINCIPLE OF OPERATION ................................................................................. 7
4. WORKING WITH CONTROL PANEL...................................................................... 8
4.1. CONNECTIONS .................................................................................................... 8
4.2. SELECTING PRODUCT AND PERFORMING MOISTURE MEASUREMENTS ..................... 10
4.3. TREND VIEW ..................................................................................................... 13
4.4. ENTERING CORRECTIONS AND PARAMETERS ....................................................... 15
4.5. VIEWING ARCHIVE DATA ..................................................................................... 23
4.6. SETTING TIME AND DATE .................................................................................... 24
5. INSTALLATION ..................................................................................................... 25
6. TROUBLESHOOTING .......................................................................................... 27
7. DIMENSIONAL DRAWING ................................................................................... 29

General safety recommendations
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General safety recommendations
The product is designed for industrial use. Installation and service must
be carried only out by trained and authorized personnel and according
to valid standards.
Before making any electrical connections, ensure that power supply
voltage and frequency meet the specifications provided on the labels of
devices and in this manual.
Incorrect connection may cause damage to the device. When installing,
always refer to relevant safety regulations.
Before carrying out any welding work near the device, make sure that
the device is disconnected from the power supply.
Do not use the device with damaged insulation of cables. In the case of
damage to the cable, disconnect the device from the power supply and
contact manufacturer or local dealer for cable replacement.
In case of device malfunction do not attempt to disassemble and repair
the device. Please, contact manufacturer or local dealer for repair.
Take precautions when mounting the equipment by using appropriate lift
gear, platforms and tools.

General information
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1. General information
The system of online moisture content measurement is designed for continuous
measurement of current moisture content of grain products, oil or leguminous crops
and other products at inlet and outlet of continuous flow grain dryers.
fig 1. System of online moisture content measurement
The system can be used for measuring moisture content of the following prod-
ucts:
Grain:
- wheat
- barley
- oats
- triticale
- rye
- corn
- buckwheat
- millet
- sorghum
- rice
Oil crops:
- rape
- sunflower
- jojoba
Leguminous
crops:
-peas
- lupine
- soybean
Other:
- seaweed
- coffee
The system of online moisture content measurement consists of two А315 mi-
crowave moisture sensors and control panel (fig. 1). One moisture sensor is installed
at the inlet of dryer and another is at the outlet of dryer. If grain drying complex has
two drying shafts, one moisture sensors can be installed at the outlet of each shaft.
Control panel is installed at the operator station and intended for monitoring of
input and output flow moisture. Information about grain moisture and temperature is
displayed in digital form and in the form of charts (trends).

General information
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Control panel allows adjusting scaling settings of two moisture content current
loop outputs for use in automation systems, storing correction coefficients for meas-
ured moisture content of every product, time-averaging of measurement results and
other functions described in this manual.

Specifications
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2. Specifications
Sensor type .................................................................. microwave;
Measuring mode ........................................................... continuous;
Measuring range .......................................................... 5 – 40%;
Moisture content measurement error (up to 18%) ........ ±0.5% max;
Moisture content measurement error (18-40%) ........... ±1% max;
Product temperature ..................................................... +5ºС – +55ºС;
Ambient temperature ................................................... 0ºС – +55ºС;
IP rating ....................................................................... IP65;
Communication protocol ............................................... RS-485;
Cable length between sensor and control panel .......... up to 100 m;
Analog output ............................................................... 4-20 or 0-24 mA;
Analog output loading capability .................................. 400 Ω max;
Sensor weight ............................................................... 6.5 kg;
Control panel weight ..................................................... 4.5 kg;
Control panel power supply .......................................... 100-240VAC / 50-60Hz;
Sensor power supply .................................................... 24VDC.

Principle of operation
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3. Principle of operation
The principle of sensor A315 operation is based on the considerable difference
of the permittivity of dry substances and water at ultra-high frequencies (UHF).
The feature and important advantage of A315 moisture content sensor is that
due to simultaneous measurement of resonant frequency and amplitude of the reso-
nance and special processing algorithm, moisture content measurements become
practically independent of product bulk density.
The sensing element is based on a ring resonator. The resonator has a cavity
formed by a PTFE tube for grain flow. Interaction of grain flow with resonator field in-
side the tube influences parameters of the resonator. Temperature sensors in meas-
uring channel allow automatic correction of measured value of moisture content from
the grain temperature.
Electronics of the sensor consists of two units – UHF module and data pro-
cessing module that control frequency response of measurement resonator, provide
necessary calculations and transfer of data to control panel via RS-485 interface.
fig 2. Principle of operation
When the measuring channel is empty, the resonator has resonant frequency
F0 and amplitude A0 (fig. 2). When the channel is filled with grain with certain mois-
ture content, the resonant frequency and amplitude decrease to F1 and А1 respective-
ly. With the increase of moisture content in measured product, resonant frequency
and amplitude decrease even more (F2 and А2). Simultaneous measurement of res-
onant frequency and amplitude allows determining moisture content independently of
grain density.

Working with control panel
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4. Working with control panel
4.1. Connections
Control unit is designed to work with two A315 grain moisture content sensors.
One of the sensors has address A, and the second one – address B.
fig 3. Wiring diagram
Control panel is supplied with two pre-wired cables (3 m each) for connecting
the sensors. This allows to quickly plug the sensors and check their operation before
installation on the grain dryer and to learn how to work with the control panel.
For installation on the grain dryer 7-terminal junction box should be mounted at
the distance of up to 3 m from a sensor and sensor cable should be connected to it.
Communication lines (4 twisted pairs) of the required length (up to 100 m) from each
junction box are wired to the operator station where control panel is installed. Con-
nections should be performed according to wiring diagram shown in fig. 3.
In order to check operation of measurement system place both sensors on a ta-
ble, connect the cables from control panel to sensors A and B and power up the con-
trol panel. After startup the display should look as shown in fig. 4. Two green indica-
tors show that sensors are ready for measurements.

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fig 4. Control panel screen after system startup

Working with control panel
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4.2. Selecting product and performing moisture measurements
The work with moisture content sensors starts with product selection. Press
to open product selection menu (fig. 5).
fig 5. Product selection menu
Select the product and confirm selection by pressing . Now moisture
sensors are ready to work with the selected product. Select mode and fill
the measurement channels of the sensors with grain. Green indicators will turn white
and measured value of moisture content for each sensor will be shown on the dis-
play (fig. 6).
fig 6. Instantaneous and averaged moisture values
Small numbers in the bottom-left and bottom-right corners of the display repre-
sent instantaneous measured values for each sensor. Large numbers in the center of
the display show moisture contents values averaged over time (see section 4.4 for
averaging settings).

Working with control panel
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When grain is removed from moisture meters, the current values of the moisture
will show zero, but the average values will retain their previous readings (fig. 7). Av-
eraged values can be reset by pressing on them when the measurement channel of
the sensor is empty.
fig 7. Showing average moisture values
Special mode can be used in order to simulate flow measurement
process in the moisture control system (fig. 8). It allows obtaining an average mois-
ture value for the same product based on the results of several single measurements.
After selection of the product press button to switch to “Laboratory” mode
(fig. 8).
fig 8. “Laboratory” mode
By default “Number of measurements” line should read 4. Press but-
ton and fill moisture sensor A with a portion of grain. Wait for sound signal and the
appearance of figure “1” in “Conducted measurements” line. Remove grain from the
sensor and then fill in the sensor with again to see figure “2” after the signal. Repeat
the procedure four times. After the four measurements “Moisture %” window would

Working with control panel
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display average of moisture content of the product based on four sample measure-
ments. After this the similar procedure can be performed for sensor B (fig. 9).
fig 9. Product moisture measured in “Laboratory” mode
In certain cases the number of measurements in mode should be
increased for correct measurements. This is especially important for wet grain (more
than 18% for grain and leguminous products and more than 13% for oilseeds) be-
cause wide dispersion of moisture and density of samples is usually observed. For
example in order to obtain correct measurement results for wet corn the number of
measurements should be increased to 10.
In order to change the number of measurements press on the digit following
“Number of measurements” line and enter a new number using the appeared numer-
ic pad (fig. 10), confirm input by pressing .
fig 10. Selecing number of measurements for “Laboratory” mode
After setting the number of measurements, press button and perform
10 fillings to get the correct moisture content value.

Working with control panel
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4.3. Trend view
Control panel provide an option to display trends of measured grain temperature
and moisture content for the time period since the sensor start up. Press
button to view trends. The screen will display the last 10 minutes trend of moisture
content for sensor A (fig. 11).
fig 11. Moisture content trend
The blue line shows the instantaneous (current) value of moisture, the red line
shows the time-averaged value. By pressing the buttons and you can turn
on and off the current and average value trends. To see trends for different time peri-
ods press arrow buttons and below the chart.
fig 12. Watch line
To view the trend of grain temperature in sensor A click , to view the trend of
moisture content in sensor B press , to view the trend of grain temperature in
sensor B press . To see the value of either moisture or temperature for each of

Working with control panel
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the sensors at a particular moment of time click on a trend section corresponding to
this moment and read the value in the "Watch line" line at the bottom of the screen
(fig. 12).
The scale of vertical axis can be changed. To change the upper limit press on
the limit value and enter a new value using numeric keypad. The limit can be
changed in increments of 5% (fig. 13). Press button on the numeric keypad to
complete the operation. Similarly you can change the lower limit value of the trend in
increments of 5% by pressing the lower limit of vertical axis.
fig 13. Changing vertical axis limits
“Trends” mode can be accessed from mode (fig. 4). Press the figure
of instantaneous value of moisture content or temperature for chosen sensor to
switch to “trends” mode.

Working with control panel
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4.4. Entering corrections and parameters
The system of online moisture control allows adjusting scaling parameers of cur-
rent loop outputs and applying individual correction and averaging coefficients for
each sensor.
Press button to enter “Settings” menu. The display will show pass-
word enter screen. Press symbol * on the display to see keypad for entering pass-
word (fig. 14). Enter “315” as the password using the keyboard and press but-
ton. “Settings” menu is shown in fig. 15.
fig 14. Password screen
fig 15. “Settings” screen
Correction parameters can be selected for each sensor individually. If the sys-
tem operates two sensors together or both of them are switched off than at the top of
the display the following warning text will appear: “Select one sensor”. In order to se-
lect the required sensor press buttons and located in the upper right corner

Working with control panel
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of the screen. The selected sensor is indicated by the corresponding letter in the left
top corner of the panel (fig. 16).
fig 16. Selecting sensor А
Press button to read parameters from sensor A (fig. 17).
To select mode for current loop output press button or and
confirm selection by pressing . Check the settings by pressing
.
Current loop output is adjusted by setting moisture values for minimum and
maximum currents. Fig. 17 shows that 4-20 mA mode is selected - the minimum cur-
rent value 4 mA corresponds to 4% moisture content and the maximum current value
20 mA corresponds to moisture of 20%. That means that if moisture of 12.9% is indi-
cated on your sensor A than the current output signal shall be 12.9 mA
fig 17. Current output settings
Moisture content values for minimum and maximum currents are set in the fol-
lowing manner. To change the value for the maximum current press on the figure in

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“for minimum current” line. Enter new value and press (fig. 18). Press
and in the “Current output settings” to apply and check new
settings. The moisture content value corresponding to the minimum current can be
changed in similar way.
fig 18. Adjusting current output settings
A315 sensor can perform measurements in mode or .
Moisture calculation in “Mode AF” is performed using two algorithms. Calculation al-
gorithm is selected automatically by the sensor depending on grain moisture content
and temperature. Selected method is indicated with number “1” or “2” in “Moisture”
line. Both algorithms allow to apply correction coefficients.
Fig. 17 shows figure “1” in “Moisture” line with measured moisture content value
reading 13.3 %. It means that moisture calculation is performed using algorithm “1”
and only correction coefficient “1 Offset” is valid for this algorithm.
fig 19. Entering correction for algorithm 1
If for grain sample with known moisture content, for example, 13.8% the sensor
reads 13.3 %, then the correction of 0.5% must be applied. To input correction press

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“1 Offset - 0.0%” and enter “0.5%” confirming input by pressing . After this the
“Moisture” line should read 13.8% (fig. 19).
fig 20. Algorithm 2
Algorithm 2 uses Bulk Density Coefficient (BDC) (fig. 20). Sensor A315 is cali-
brated for different products with bulk densities (test weight) as per Table 1.
Table 1.
PRODUCT
Bulk density (test weight)
kg/l
Lb/bu
Rape
0.646
50.19
Barley
0.702
52.54
Wheat
0.789
61.32
Oats
0.560
43.51
Corn
0.726
56.40
Rye
0.713
55.39
Lupine
0.810
62.90
Triticale
0.711
55.24
Buckwheat
0.608
47.23
Millet
0.726
56.40
Sunflower
0.415
32.24
Peas
0.810
62.90
Soybean
0.717
55.70
Sorghum
0.454
35.27
Rice
0.514
39.93
Jojoba
0.574
44.59
Seaweed
0.480
37.29
Coffee
0.685
53.22

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When it is possible to determine bulk density of the custom product then correc-
tion coefficient “2 BDC” may be tuned for better measurement accuracy. For exam-
ple, the measured bulk density of corn passing through sensor is 0.810 kg/l. Accord-
ing to Table 1, bulk density of corn for which the moisture sensor was calibrated is
0.726 kg/l. Then the value of BDC correction can be calculated:
«BDC» = 0.726/0.810 = 0.896
Changing the value of "BDC" is carried out by analogy with the changing of the
"Offset" correction. "BDC" can be further adjusted manually to achieve better agree-
ment of sensor’s readings with laboratory result within ±1.0% error. Increase of
"BDC” value leads to increase in moisture readings and vice versa. Recommended
step when changing “BDC” value is 0.01-0.02.
Moisture correction shall be performed only when measurement channel of the
sensor is filled with grain to know which correction shall be entered - “1 Offset” or “2
BDC”.
is more preferable because it provides the most accurate measure-
ment of moisture at the grain dryer outlet for products with temperature up to 40˚С.
When grain temperature at dryer outlet is higher and moisture contents if higher
at the inlet it’s preferable to use , however this increases measurement er-
ror. The choice of specific measurement mode must be made according to on-site
conditions and the results of laboratory measurements.
To change the mode press button . Than will appear that
confirms mode changing (fig. 21).
fig 21. Changing moisture measurement mode
When A315 sensor shows non-zero moisture content value with empty meas-
urement channel or green light indicating the readiness for measurement is off, that
means the sensor requires zero calibration. To perform calibration empty the meas-

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urement and press button on the screen. Calibration screen
will appear (fig. 22).
fig 22. Calibration
Press and after the calibration the screen should show “– Moisture
0.0%” (fig. 23). Calibration is finished and the sensor is ready for measurements.
fig 23. “Settings” screen after the calibration
To access service functions menu (fig. 24) press button.
The left area of the screen displays the table of target moisture levels for drying
process for each product. The signal is sent to operator when the target value of
moisture content for selected product is achieved. Moisture content control mode can
be enabled for each sensor individually by pressing button.
For example, the target moisture content for corn is set at 15% (fig. 24). Sound
alarm will be triggered when measured moisture content will become lower than the