Vishay JetWeigh-W User manual

Important Notices:
(1). This equipment has been tested and found to comply with the limits for a
Class B digital device, pursuant to part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses and can radiate radio
frequency energy and, if not installed and used in accordance with the
instructions, may cause harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a particular installation. If
this equipment does cause harmful interference to radio or television reception,
which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following
measures:
-Reorient or relocate the receiving antenna.
-Increase the separation between the equipment and receiver.
-Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.
-Consult the dealer or an experienced radio/TV technician for help.
(2). Changes or modifications to this equipment not expressly approved by the
party responsible for compliance (Vishay Israel Ltd.) could void the user’s
authority to operate the equipment.
(3). The antenna used for the load cell transmitter must be installed to normally
provide minimum separation distance of at least 20 cm from all persons and must
not be co-located or operating in conjunction with any other antenna or
transmitter.
The handheld terminal is portable but restricted to occupational/controlled use
only. It is not authorized for consumer or general population use. Personnel using
the terminal must be trained regarding RF exposure and its control.
Vishay makes no representation or warranties of any kind whatsoever with respect to the contents
hereof and specifically disclaims any implied warranties or merchantability or fitness for any
particular purpose. Vishay shall not be held liable for errors contained herein or for incidental or
consequential damages in connection with the furnishing, performance, or use of this publication or
its contents. Vishay reserves the right to revise this manual at any time and to make changes in the
contents hereof without obligation to notify any person of such revision or changes.
Cover photo courtesy of the USAF

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Table of Contents
Section I - General Information
1.1 INTRODUCTION .................................................................................................................... 1-1
1.2 SYSTEM COMPONENT DESCRIPTIONS ............................................................................. 1-2
1.2.1 Wireless Handheld Terminal .......................................................................................................................... 1-2
1.2.2 Wireless Load Cells ......................................................................................................................................... 1-2
1.2.3 Load Cell Adapters .......................................................................................................................................... 1-2
1.2.4 Thermal Printer ................................................................................................................................................ 1-2
Section II - Pre-Operation
2.1 PRE-OPERATIONAL PROCEDURES .................................................................................... 2-1
2.1.1 Load Cell Jack Point Configuration ................................................................................................................ 2-1
2.1.2 Preparation for Aircraft Weighing .................................................................................................................. 2-1
2.2 TERMINAL SETUP ................................................................................................................ 2-2
2.2.1 Setup Screen Options ..................................................................................................................................... 2-2
2.2.2 Main .................................................................................................................................................................. 2-2
2.2.3 Gravity Factor Compensation ......................................................................................................................... 2-3
2.2.4 A/C .................................................................................................................................................................... 2-3
2.2.5 Channel ............................................................................................................................................................ 2-4
2.2.6 Changing Channel ID and Location ................................................................................................................ 2-4
Section III - Operation
3.1 LOAD CELL POWER UP ....................................................................................................... 3-1
3.2 TERMINAL POWER UP ......................................................................................................... 3-1
3.3 AIRCRAFT WEIGHING CYCLE ............................................................................................. 3-1
3.3.1 Zeroing ............................................................................................................................................................. 3-1
3.3.2 Lifting ................................................................................................................................................................ 3-3
3.3.4 Removing ......................................................................................................................................................... 3-5
3.3.5 Rezeroing ......................................................................................................................................................... 3-5
3.3.6 Weighment Report .......................................................................................................................................... 3-5
Section IV - Weighing History
4.1 RECALL A RECORD FROM THE HISTORY FILE................................................................. 4-1
4.2 RECALLING AIRCRAFT FROM THE LIBRARY .................................................................... 4-1
4.3 AIRCRAFT NOT RECORDED IN THE LIBRARY ................................................................... 4-1
Section V - Troubleshooting
5.1 TROUBLESHOOTING OVERVIEW ....................................................................................... 5-1
5.2 LED STATUS INDICATORS ................................................................................................... 5-1
5.3 TYPICAL PROBLEMS AND SOLUTIONS ............................................................................. 5-1
5.4 CHANGING RF CHANNELS .................................................................................................. 5-2

Page 1-1
IntroductionIntroduction
IntroductionIntroduction
Introduction
Section I - General Information
1.1 INTRODUCTION
This manual provides information on the operation of
JetWeigh-W™WirelessAircraft Weighing System se-
ries aircraft electronic weighing kits manufactured by
Vishay SI Technologies. JetWeigh-W™Wireless Air-
craft Weighing Systems (Figure 1-1) integrate state-
of-the-art wireless communication, digital weight pro-
cessing, and high-accuracy hermetically sealed load
cells. Combined technologies from Vishay Revere
Transducers and Vishay RFWaves results in an accu-
rate, high-reliability, robust, and easy to use Wireless
Aircraft Weighing System.
JetWeigh-W kits are designed primarily for the weigh-
ing of aircraft and aerospace vehicles, but can be
used for other precision weighing applications, as well
as for the calibration of force generating machines.
The kits have been calibrated using dead weight ma-
chines. These machines are maintained to better than
±0.001% with respect to the nominal weight value. The
degree of uncertainty for all of the individual weights
is approximately ±0.005% with respect to true values.
All readings are corrected to standard gravity factor
“g”as required by MlL-W-7327C.
High capacity JetWeigh-W kits with load cell capaci-
ties of 200,000 lb are calibrated on Vishay Revere’s
high capacity precision hydraulic transfer standard.
On completion of this calibration, the JetWeigh data is
verified on the dead weight machine up to the 100,000-
lb point. Maximum acceptable deviation between the
transfer standard and dead weight data is ±0.05%.
Both the dead weight machine and the transfer stan-
dard are secondary standards and are directly trace-
able to NIST.
It is recommended that the kit be returned to the fac-
tory for routine calibration every twelve (12) months or
sooner if trouble is observed or erroneous readings
are suspected.
The load imposed on a load sensor produces an
output signal directly proportional to the load applied.
The signal is transmitted through a wireless channel
to the JetWeigh handheld terminal where the mea-
surement is processed. Analog load sensor signals
are processed digitally to remove linearity errors,
latitude and altitude effects. Presentation in pounds
or kilograms is selectable by the operator. An
integral printer provides a permanent record of all
pertinent weighment information including any
deviations that are accepted by the operator.
Figure 1-1. Typical JetWeigh-W™ Aircraft Weighing System

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IntroductionIntroduction
IntroductionIntroduction
Introduction
1.2 SYSTEM COMPONENT
DESCRIPTIONS
Each kit contains the necessary equipment for weigh-
ing an aircraft with the exception of specialized jacks .
Kit contents include 3 to 5 wireless load cells, a rug-
ged handheld PC user terminal, a thermal printer, power
adaptors and a power cord, a center of gravity acces-
sory kit, and a rugged fiberglass carrying case.
1.2.1 Wireless Handheld Terminal
The wireless handheld PC terminal features a graphic
color touch screen display, intuitive step-by-step op-
eration, and advanced functions such as CG calcula-
tion, aircraft type library, weighing history, latitude and
altitude adjustment. It communicates with up to 5 re-
mote wireless load cells thereby eliminating cumber-
some interconnecting cables.
Units operate in a world wide license-free band - 2400
MHz to 2483.5 MHz and comply with all FCC, CE,
ETSI standards.
Synchronized sampling of all load cells ensures cor-
rect weighing even under severe vibration and oscilla-
tions conditions.
1.2.2 Wireless Load Cells
Each kit contains from 3 to 5 hermetically sealed wire-
less load cells. These cells are precision devices and
will withstand 150% overload without damage. Drop-
ping a load cell, however, could damage the elec-
tronic box, the diaphragm, or other components af-
fecting its operation or accuracy.
Each cell has a tapped hole on the bottom to receive a
plug or a ring jack adapter. The top surface has a ¾”
radius concave surface to receive either the spherical
surface of an adapter or the aircraft jack pad directly.
NOTE: Load cells of identical capacity are interchange-
able. However, load cells and spherical adapters are
color coded as matched sets. When changing load
cell locations, make sure that the spherical adapter/
load cell combination remains intact.
1.2.3 Load Cell Adapters
For the purpose of mounting load cells under varying
physical arrangements, several adapters are provided
(See Figure 1-2):
a) Plug and ring adapters for securing the cell to
the hydraulic jack.
Figure 1-2. Jack Adapters
b) Spherical adapters to allow interfacing transi-
tion between the cells and conical jack pads or
flat surfaces
c) Axle adapters which allow transition from the
cell to the cylindrical surface of the axle.
1.2.4 Thermal Printer
JetWeigh-W systems ship with a high speed thermal
printer. At the end of each weighment, aircraft specifi-
cations, resultant weight data, and all other calcula-
tions can be printed and stored for future reference.
The printer is compact, easy to install, and require
minimal maintenance. A complete reference manual
for the printer is included with the kit.

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Pre-operationPre-operation
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Pre-operation
Section II - Pre-Operation
2.1 PRE-OPERATIONAL PROCEDURES
Section II presents all procedures that must be performed
prior to actual aircraft weighment. Since the JetWeigh-
W system is completely wireless, no cable connection/
installation procedures are required. With an operating
range of 220 feet (70 meters), it should be easy to lo-
cate all load cells and the handheld terminal in functional
proximity to one another.
2.1.1 Load Cell Jack Point Configuration
JetWeigh-W Systems accommodate jack point configu-
rations for 3-point, 4-point (helicopter or fixed wing) and
5-point aircraft. Recommended deployment of the load
cells is shown in Table 2-1. Make sure to match the load
cells and the mechanical adapters to ensure good re-
peatability of weighments.
2.1.2 Preparation for Aircraft Weighing
1. Review the Equipment List of the aircraft being
weighed. Update the list as required. Make sure the
particular equipment, which will normally be installed,
but is missing at the time of the weighing, is added in
the later calculations.
2. Remove all equipment, which will not be included in
the above list.
3. Clean the aircraft to remove accumulated dirt, grease
and trapped water.
4. Fill the oil tanks to a known quantity. Fill all reser-
voirs, such as anti-icing fluid, to capacity.
5. Drain fuel tanks. If draining is not practical, fill the
tanks to capacity. Add or account for unusable fuel.
6. Determine the unit weight of fuel. Obtain a sample
from the fuel tank with the supplied fuel dipper (CG
kit) and pour the sample into the test tube. Using the
hydrometers (CG kit), the weight of fuel in pounds per
gallon can be observed. Variations in fuel weight, par-
ticularly in the case of jet aircraft, can cause
appreciable difference in the final empty weight and
CG determinations. Be alert for partially filled non-
symmetrical fuel tanks.
7. With tricycle gear aircraft, it is often desirable to
level the aircraft as closely as possible before lifting
on the jacks. Changing oleo strut extensions can do
this.
8. A stabilizing period of 20 minutes running concur-
rently with warm-up period is advisable. When using
jack adapters, be sure the adapter is fully threaded into
the cell. With ring adapters, make sure it is centered
flush on the ram before tightening the set screws.
CAUTION
Use proper adapters to prevent jacks from
slipping or buckling. Damage to the aircraft or
inaccurate weight readings may result if improper
adapters are used. Never apply load to the rim of
the cell.
Color coded spherical adapters must be used in
conjunction with color coded load cells.
9. It is recommended that the load sensors be exer-
cised prior to performing an actual weighment.
Exercise the load sensors 2 – 3 times by lifting the
aircraft with the load sensors and jacking system in
place.
10. The JetWeigh-W is programmed to identify left,
right, nose, or the sum of both sensors on a bogie.
This requires that specific channels (load cells) be
dedicated to a specific location when preparing for
a weighment. These location identifiers will nor-
mally appear on the printout. However, they will not
appear during 1 and 2 channel operation. Table 2-1
shows the recommended layout for various configu-
rations.
3 Load Cells
Channel 1 Red Left
Channel 2 Yellow Right
Channel 3 Blue Nose
4 Load Cells Helicopter Fixed Wing
Channel 1 Red Fwd Left Left
Channel 2 Yel Fwd Right Right
Channel 3 Blue Aft Left Nose
Channel 4 Orng Aft Right Spare
5 Load Cells
Channel 1 Red Left (1)
Channel 2 Yellow Right (1)
Channel 3 Blue Left (2)
Channel 4 Green Right (2)
Channel 5 White Nose
Table 2-1. Jack Point Configuration

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2.2 TERMINAL SETUP
Figure 2-1 shows the default power up screen for the
handheld terminal. Three primary function modes;
Setup, Weighing, and System, are accessed by touch-
ing the associated soft keys at the bottom of this screen.
In this Section, system setup is defined prior to actual
aircraft weighing. Touch (with stylus - throughout) setup
on the lower left corner of the screen to enter setup
mode. Vishay recommends that setup be performed
with the power adapter plugged in to conserve battery
charge for actual wireless weighment.
NOTE: The Handheld Terminal will operate for approxi-
mately eight hours on battery power alone.
2.2.1 Setup Screen Options
Setup mode consists of four sub-menu selections lo-
cated on the left side of the screen. Step through each
sub-menu sequentially, starting with
Main and proceed-
ing to Gravity , A/C , and Channel . After entering valid
parameters for each sub menu, the system is ready
for “live”weighing operation.
NOTE: For screens that require data entry, touch the
data entry box and an alphanumeric keypad will ap-
pear as shown in Figure 2-2.
2.2.2 Main
Touch “
Main ”on the left margin of the screen to enter
fundamental system parameters (Figure 2-3).
a). Units – use the drop-down menu to select
lb (pounds) or kg (kilograms)
b). Date – use the drop-down menu to set the
correct date
Figure 2-1. Initial Power Up Display
Figure 2-2. Data Entry Keypad Displayed
Figure 2-3. Main Parameter Selections

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c). Stability –use the drop-down menu to select
Normal, Relaxed, or User. Ambient air currents
always affect weighments to some extent. If the
aircraft is weighed indoors (hanger environment),
select normal to compensate for minor air current
uplift effects. If the plane is out of doors, select
relaxed (twice normal) to achieve slightly more
compensation. Selecting user allows specific time
and amplitude values to be entered for precise
compensation (see “d”).
d). “T”represents the duration period and “A”repre-
sents the amplitude of an interference that will
not be considered as a change in weight. As long
as the weight readings are within the rectangular
TxA, weight readings are considered to be stable.
e). Averaging - use the drop-down menu to select 1,
2, 5, 10, or 50 conversion averaging. Averaging
applies a low-pass filter on the weight readings to
eliminate the effect of vibrations.
f). Zero tracking –touch the Zero Tracking check box
to activate the zero tracking function. Zero
tracking eliminates minor electronic variations
around the calibrated zero value.
2.2.3 Gravity Factor Compensation
The Figure 2-4 Gravity menu consists of two grayed out
text boxes that display the calibration location data, and
two enabled text boxes for entry of the operation latitude
and elevation. Enter the exact latitude and elevation of
your installation location.
2.2.4 A/C
The
A/C menu (Figure 2-5) allows users to choose
from a predefined list of over 200 aircraft, or define
the dimensions of a custom (“Other”) aircraft. This
menu also allows the entry of the aircraft serial num-
ber and the user’s ID for printouts and future refer-
ence, if saved.
a). Touch list and then model to view aircraft types
and configurations.
b). Touch the “Other”checkbox to activate entry of
a new Manufacturer/Model combination. Key in
the manufacturer and model number in the
respective boxes beneath “Other”.
c). Use the A/C type drop-down menu to select the
new aircraft type.
d). Key in the serial number and user ID for the
new aircraft configuration. All entered informa-
tion will be included in the final weighment
printout.
Figure 2-4. Gravity Parameter Selections
Figure 2-5. Aircraft (A/C) Parameter Selections

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2.2.5 Channel
Touch the
Channel Selection drop-down menu (Figure
2-6) to choose from one of five standard aircraft con-
figurations. The selections are:
a). 3 sensors (load cells –throughout)
b). 4 sensors –helicopter
c). 4 sensors –fixed wing aircraft
d). 5 sensors
After selection, the configuration is displayed as a
wheel-by-wheel, or jack point-by- jack point schematic
diagram and the channel allocation table reflects ex-
act placement locations. Double touching a channel
ID number changes the channel allocation table and
schematic to a new aircraft (based upon ID entry in
segment “d”of paragraph 2.2.4).
After completing all sequential parameter entries, the
JetWeigh-W System is ready for “live”weighing op-
eration.
Figure 2-6. Load Cell Channel Configuration
2.2.6 Changing Channel ID and Location
To change logical channels, as shown in Figure 2-7,
double click the ID field at the channel selection table.
This opens an editable field at that ID, and a numeric
keypad will pop up.
Using the numeric keypad, you can assign any chan-
nel to that location. Channel input termination is com-
pleted by touching the enter key on the numeric key-
pad.
NOTE: Users are responsible for maintaining the logi-
cal integrity of each assigned location ( making sure
that a single channel is allocated to a single location).
Figure 2-7. Changing Channel ID Information

Page 3-1
OperationOperation
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Operation
Section III - Operation
3.1 LOAD CELL POWER UP
Place load cell equipped jacks in position beneath air-
craft jack points as shown in Figure 3-1. Orient the
load cell transmitter housing (rectangular box attached
to the cylindrical cell) of each cell parallel to the neu-
tral axis of the aircraft. Walk to each cell and press the
power “ON”button. Check the green LED on each cell
transmitter housing to see that it is illuminated and
blinking at a rate of approximately one Hz (once per
second).
NOTE: If the green LED is blinking at a rapid rate, this
indicates that load cell internal battery capacity is low
- approximately one hour of work is left (without charg-
ing). Recharge the cell battery as soon as possible.
3.2 TERMINAL POWER UP
Figure 3-2 depicts the handheld terminal in its RF
equipped carrying case. Press the terminal power but-
ton and observe the initial screen as depicted at right.
NOTE: The Operation LED should remain in the off
state until actual weighment begins.
3.3 AIRCRAFT WEIGHING CYCLE
Prior to weighment, Vishay recommends that the air-
craft be raised and lowered 2 or 3 times (“dry runs”)
to acclimate system load cells. Actual weighing is ac-
complished in six steps; Zeroing, Lifting, Weighing,
Removing, Rezeroing, and Reporting using the weigh-
ing menu. Each step must be performed sequentially
and successfully before proceeding to the next step.
To begin, touch the Weighing menu block on the lower
tool bar with the stylus and observe the Zeroing screen
depicted in figure 3-3.
3.3.1 Zeroing
Under ideal conditions, with load cells powered up and
in a no load condition (no jack contact with aircraft
jack points) the reading for each channel should be
zero. However, in reality, it is often necessary to “zero
out”minor variances in any or all of the system cells.
The zeroing screen (Figure 3-3) allows for individual
or complete zeroing of any/all system cells.
During the zeroing process, the terminal retrieves cali-
bration, serial number, and other critical data from
each load cell. If data cannot be accessed, one of the
Figure 3-4 error screens (next page) will appear. Any
weighment which does not include all vital data from
each cell will not be valid, so the user is prompted and
given the choice/chance to try again.
Figure 3-1. Aircraft with Jacks Positioned
Figure 3-3. Zeroing Screen/Menu
Figure 3-2. Handheld Terminal Enclosure