Ag-Tester HT101V User manual

1
HT101V Reference Manual
Overview
The HT101V from Ag-Tester is our handheld tester
designed to diagnose valve components on agricultural
machinery.
Valves tested include:
1- Boom Control Valves
2- Servo Rate Control Valves
3- PWM Control Valves
The top section of the HT101V is the meter. The user
can make measurements including Voltage, Frequency
and Resistance.
The lower part of the HT101V is the diagnostic and valve control center. When used with the “In-Line”, Tester- Tee
harness, the HT101V will monitor the supply and control voltages being provided by the display. Test terminals are built
into the HT101V to allow metering connections to be made without disturbing the connectors and cables associated
with the control console. Valves can be fully tested, in-line, independently from the display.
When used with the “Stand- Alone”, Tester Tee harness, any valve can be fully tested on the bench.
The back panel provides connections for inputs and charging along with the magnetic RAM mount.
Heat Sink- Absorbs heat RAM Mount
generated while driving Attaches here with
PWM Valves. Magnet.
Input Connection-
Connect the Tester Tee
Harness here for In-Line or
Charger Connector
Stand-alone tests.

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Meter functions
The “Meter Function” switch selects the type of
measurement being made. Select from the following:
VOLTS 0 to 50 Volts DC with automatic polarity sensing
FREQ Frequency 0 to 1000 HZ
CONT “Continuity” or “Ohms” 0 to 2000
The “Connected Point” switch selects the testing method.
There are 4 options. TEST, PATCH, COAX, or BATT CHECK
When dialed to TEST the standard meter
test leads are installed in the RED outlined
lead jacks. The meter can then be used as
you would a standard test meter.
Dial to PATCH to use the Patch Cables
connecting at the Green outlined lead
jacks. This allows an easy connection to
the wires connecting the Display console
to the control valve.
Setting the CONNECTED POINT to COAX allows for an easy connection to a TNC type coax
connector. Most GPS receivers send 5 volts to the antenna to operate an internal amplifier.
Disconnect the cable from the gps antenna and re-install at COAX on the HT101V. When VOLTS is
selected you should see 5 to 12 volts on the meter indicating a good connection from the
antenna connection to the gps receiver.
When dialed to BATT CHECK and VOLTS the
meter indicates the current internal battery
voltage. Fully charged it may read as high as 13.5 VDC. The tester
will function properly until below 12 volts. No wire connection is
required. Battery can be checked while performing other tests.

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Diagnostic Functionality and Valve Testing Functions
The Tester Function Switch located at the lower
right. When dialed to any position other than OFF,
the meter functions are all available.
Set to MONITOR to make tests on the control cable
coming from the display to the control valve.
When connected for In-Line testing there are as
many as four (4) possible connections. A four wire
valve will have a ground, main power, and two
control lines. The HT101V makes these connections
available as Test Jacks and any voltage present on a
line will light the associated LED.
Test Jacks and LEDs are colorized to indicate:
RED = Supply Voltage from Display
Yellow= Open Valve command voltage from display
Green= Close Valve command voltage from display
Black= Ground
A two wire control valve will only use the Yellow/
Green, open- close command voltages.
TEST SERVO and TEST PWM are colorized matching drive controls with the correct valve type. TEST SERVO is in GREEN
while TEST PWM is in Yellow. There are times when a servo valve is actually controlled with PWM pulses. Follow
instructions carefully. The DRIVE controls are at minimum when counter clockwise and maximum at clockwise.
The SERVO TEST switch is a “center off” momentary contact toggle switch. Holding the switch to the left drives the valve
open and lights the YELLOW LED. Holding the switch to the right drives the valve closed and lights the GREEN LED. With
the DRIVE CONTROL fully clockwise maximum power is sent to the valve. The speed of the valve operation is
determined by the DRIVE CONTROL.
PWM TEST uses the DRIVE CONTROL to set the width of the drive pulses. The TEST switch is a momentary contact
switch. When testing PWM type valves always start with the drive control fully counter-clockwise. Press TEST and slowly
increase the PWM Drive. PWM Valves are two wire valves.
There are four wire valves that respond to PWM pulses for drive control. In those cases, the SERVO TEST switch is used
to control the direction of movement and the PWM DRIVE CONTROL sets the speed of valve operation.
Keep both drive controls at minimum. Then only use ONE to set the valve speed and complete the tests.

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Types of valves to be tested
The HT101V is designed to be compatible with “Any” valve on “Any” machine. Specific valve types require specific
control voltages to operate correctly. The following explains the differences. It is important to know what type of valve
you’re dealing with to insure the best level of diagnosis.
Solenoid Valves- A simple On/ Off valve that uses a charged coil to engage the valve. 12 Volts present activates the
coil and operates the valve. Removing 12 volts dis-engages the valve. Polarity normally doesn’t matter.
Motorized Ball Valves- These valves operate at full speed all the time. They many times will have three wires. Plus
12 volts constant, Ground or minus 12 volts, and a signal line. The signal wire uses 12 volts to open the valve and lack of
12 volts closes the valve. There are 4 wire motorized ball valves. Here 12 volts and ground are supplied constantly. The
other two wires signal open/ close by supplying 12 volts but reversing the polarity to signal open/ close.
Servo Control Valves- Servo valves are motorized valves designed to provide smooth control of open and close
operation. The speed of the valve is controlled by varying the voltage or drive to the motor. The motor operates at full
speed with 12 volts applied but will typically move slowly with as little as 3 volts or less. The polarity of the applied
control voltage controls the direction of operation. Control systems constantly change the control voltage to affect the
movement speed or response. As an example; a spray controller will run the control voltage to maximum when big
changes are required, then drastically drop the voltage as the target rate is reached. Fine tuning is performed at
minimum operating voltage. Servo valves may work perfectly at full voltage, “drive” but not move at all at low control
voltages.
PWM Valves- PWM means “pulse width modulated”. Modulate means, to change. PWM valves are closed when
there is no signal. The valve then begins to open as pulses are applied, so the valve is effectively opening and closing
with each pulse. The control signal voltage is turning on, then off, at a rate of about 100 times per second or 100Hz.
Applying a constant 12 volts to the PWM valve coil will run the valve at full speed.
An oscilloscope image shows the pulse width changing. The percentage of time ON is called the DUTY CYCLE.
ZERO VOLTS- 11 VOLTS- Drive Voltage changes from Zero to Eleven Volts, 100 times per second
ON about 25 percent of the time- ON about 50 percent of the time ON about 70 percent of the time
PWM Valves are two wire valves and look a lot like solenoid valves. RAVEN PWM valves reach full output at 55% drive.
DITHERING SERVO VALVES- 4 WIRE- Some servo control valves respond to PWM commands. The speed of the
valve is controlled by the pulse width of the drive signal rather than a varying drive voltage to control valve speed. They
have 4 wires with a constant Ground and Plus 12 Volts supplied. The control signal is pulse width modulated. Some
would call these valves, current controlled. RAVEN 4 wire FAST VALVES and DICKEY-john control valves are this type.

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Using the HT101V- Stand-Alone Testing
Stand-alone testing is used as a method of testing and evaluating or “bench testing” a control valve “independent of the
display”. The HT101V allows for full testing of any valve.
Use the Tester Tee Harness and adapters to fit best with the valves you’re testing. Here we’re using the TT-AE27996
Stand-alone RAVEN harness.
Boom control valves are three wire
control valves that always work at full speed.
Set the Function switch to TEST SERVO.
Hold the SERVO TEST Switch to the LEFT,
“OPEN” while increasing the SERVO DRIVE. The required drive is around seven volts. Use the PATCH
cables if you want to monitor the required voltage with the plus lead at YELLOW and the meter ground
at GND on the test jacks.
WHEN USING THE SERVO DRIVE CONTROL—TURN THE PWM DRIVE TO MINIMUM
SERVO Valves are motorized valves that are designed to be finely adjustable.
The motors run at full speed with 12 volts applied. A
minimum of two to three volts is applied to fine tune the
valve position. When failing, these valves may run
perfectly at full speed, yet not at all with lower drive
voltages. The HT101V allow you to fully test the
operational range.
Set the Function switch to TEST SERVO. Set the SERVO DRIVE control to fully clockwise. See if
the valve runs with FULL DRIVE using the SERVO TEST switch, LEFT to open and RIGHT to close. If the valve runs at FULL
DRIVE, check it with MINIMUM DRIVE. Use the SERVO DRIVE CONTROL and monitor the drive voltage at the yellow and
black test jacks. Good valves will run with as little as 3 or 4 volts of drive.
WHEN USING THE SERVO DRIVE CONTROL, SET THE PWM DRIVE TO MINIMUM
PWM Valves are two wire valves. Set the function switch to TEST
PWM. Use the momentary contact PWM TEST switch to activate the
drive. Always start the test with the PWM DRIVE control set to
MINIMUM. Push the TEST button and increase the drive. With stand-
alone tests there is not much to see. You can hear the valve coil in most
cases. The sound increases in pitch with increased drive. If the valve is
installed in a hydraulic circuit, you’ll see the hydraulic motor speed up
as the drive is increased. Control occurs at about 50 percent. There is
no reason to go to full drive clockwise position.
WHEN USING THE PWM DRIVE CONTROL, SET THE SERVO DRIVE TO MINIMUM

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Some Servo Valves respond to pulses from a PWM Drive more
accurately than a standard variable voltage drive. The HT101V is
wired so that the PWM Drive can be used with a Servo Valve.
Dial the function switch to TEST SERVO. Be sure the SERVO DRIVE
control is set to MINIMUM, COUNTER CLOCKWISE. Use the
SREVO CONTROL switch holding left to open and right to close.
The PWM DRIVE vontrol then controls the pulsewidth, thusly the
valve speed. This RAVEN FAST VALVE responds nicely with both
standard servo drive or pwm drive.
4 WIRE Dithering valves like the RAVEN FAST- 4 wire valve will test as above. A true PWM type servo will not control
with standard SERVO DRIVE. You will find this type of servo will “Run at Full Speed” with any level of standard voltage
control drive.
In-Line Testing Use In-Line Tester Tee Harness- TT-AE27995 for RAVEN
The In-Line Tester Tee harness is installed between the valve
being tested and the cable feeding the valve from the controller
display.
TO VALVE
TO DISPLAY
Once installed, the
HT101V will display the
supply voltages and
signals provided by the
display. The four “test
jacks” are connected to
the wires controlling the valve coming from the display. LED light up indicating
voltage present on the individual wires.
Four wire valves use: Red= Supply Plus Power, Yellow= Valve Open, Green=
Valve Close, and Black= Supply Negative or Ground.
Three wire valves use: Red = Supply Plus Power, Yellow= Valve open, Black= Ground or supply negative.
Two wire servo valves use: Yellow and Green. Valve open is Yellow= plus and Green= negative. The voltage reverses to
control the motor open/ closed. No power applied stops the valve.
Two wire PWM valves use Yellow and Green. Yellow is the signal drive and green is ground.

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Battery Care- HT101V and HT101S Testers
These testers are equipped with a high power, 12 volt 1000 MAH Nickel- Cadmium “NI-
Cad” battery. The testers will run about 10 hours constant without a re-charge. Re-
Charge takes about 4 hours.
The battery level can easily be checked using the voltmeter built into the tester.
Turn the tester ON, set to VOLTS, and Connected Point
to BATT CHECK. The current voltage will be
displayed.
After a full charge, it may read in excess is 13 volts, then will stabilize at about 12.2 to
12.8 volts.
Ni-CAD batteries develop a memory over time. If they are recharged after each short
usage, they will develop that memory and at some point only deliver that capacity. MAXIMUM battery life with the
strongest usage cycle is achieved by charging the battery when the voltage drops below 12.0 volts. Check the voltage as
your putting away the tester. If the voltage is 12.0 volts or less, recharge.
Use only the SMART CHARGER that came with the tester. The charger will turn
itself off when the battery is charged so there is no chance of
overcharging.
The charge indicator light turns RED when charging and when fully charged the
light turns green.
Batteries are replaced at Ag-Tester. Go to agtester.com for details.

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Tester Tee Harnessing is used with all Ag-Tester tools
The connectors used on current harnessing are selected to work with RAVEN components. Valves are connected to
other manufacturers with various functionality using adapter harnesses.
In-Line cables provide a means of “TEEING IN” at the valve. Users can watch the commands from the display or test the
valve functionality. When using In-Line harnessing, all the operational voltages are coming from the display.
Stand-Alone Cables are also cabled for RAVEN. All the RAVEN valves will connect directly and adapters can be used to fit
any other products.
Stand-Alone cables allow for the Ag- Tester HT101V to provide power to the component being tested allowing it to be
fully tested “on the bench”.
The following shows the technical side to the HT101V with “in-line” and “stand alone” cables.
Please direct questions to “contact us” at agtester.com

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Tester- Tee Harnessing
To understand the flow of circuits and over-all Ag-Tester product design, one needs to start with an understanding of
the interface harnessing, “Tester-Tee Harnesses”. Two harnesses are used for full Tester functionality.
1- In-Line Harnessing. This is used for full system diagnostic operations where the full connection from the
display to the sensor or valve is intact. Here, the system is left intact with the Ag-Tester Tool inserted in the line
feeding the Valve or Sensor in question from the balance of the system.
a. When in the “monitor mode” “Tip Jacks” are available representing each possible connection between
the component and the rest of the system. This provides a connection point for either, the Ag-Tester
Tool or another meter, oscilloscope or some other tool so tests can be performed to determine the
cause of the problem.
b. When in the other provided “modes of operation” the circuit control lines are disconnected between
the component and system balance to allow for diagnostic functions to be performed.
i. The “HT101V” allows the valve in question to be independently tested. There is no feedback to
the display circuitry.
2- Stand-Alone Harnessing. Stand-alone harnessing allows for components to be “bench tested”. Using the
stand-alone harness allows that the Ag-Tester Tool provides the operational power and signals to the devise
being tested to fully test the component.
a. Monitor mode is not used unless using the Tester as a “multi-meter” for basic tests.
b. When in other modes of operation, the type of test being performed is selected. The Tip Jacks do not
represent the “Power Supplied” “Red LED” using this function.
i. The HT101V allow for various types of valves to be completely tested. Valve drivers are included
that allows control signals for servo valves, dual drive pwm control valves and pwm control
valves. The tip jacks represent all connections except supply power, “red”, allowing for full
diagnostics of valve performance.

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Ground- Black
Signal to Close- Green
Signal to Open- Yellow
Power-Red
Ground- Black
Signal to Close- Green
Signal to Open- Yellow
Power- Red
1
(+)
Power
from
display
2
(-)
Power
from
display
3
(+)
control
valve
drive
from
display
4
(-)
control
valve
drive
from
display
5
N/C
6
Tester
GND
OUT
7
Tester
12V
Out
8
(+) Plus
Drive
to
Valve
9
(-) Neg
Drive
to
Valve
1-2-3-4-5-6-7-8-9
Tester-Tee Harnessing- Valve Harnesses as follow:
In-Line Harness for Valves- HT101V
Ag-Tester Tool HT101V
Tip Jacks and LEDs
Valve
Display
Constant
Current/
Voltage
Driver
+/-
Dual
PWM
Driver
+/-
To Display
A
B
C
D
To Valves
1
2
3
4
To Tester- 9 pin AMP