AMS SENSIT II Operation manual

L0097, Rev. D
SENSIT II
OPERATION AND SERVICE MANUAL
AUTOMATED MERCHANDISING SYSTEMS INC
255 WEST BURR BLVD.
KEARNEYSVILLE, WV 25430
304-725-6921, Fax [phone]
www.amsvendors.com
[email protected]
INTERNATIONAL A.M.S. S DE RL DE CV
KM. 9 CARR. AL CASTILLO NO. 8200
MPIO. DE EL SALTO, JAL. MEXICO 45680
5233-36-88-07-17, Fax [phone]
www.amsint.com.mx
[email protected]
Glass Front Vendor
Model 39
Frozen Food (FV)

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
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TABLE OF CONTENTS
Para Title Page
TABLE OF CONTENTS i
TABLE OF FIGURES iii
1 INTRODUCTION 1-1
1.1 SENSIT II SYSTEM 1-1
1.1.1 Guaranteed Delivery 1-1
1.1.2 Instant Refund 1-1
1.1.3 Automatic Helix Adjustment 1-1
1.1.4 Additional Benefits 1-1
1.2 HEALTH AND SAFETY 1-1
1.2.1 H&S Specifications 1-1
1.2.2 H&S Software 1-1
1.2.3 H&S Protection 1-1
1.3 MODEL IDENTIFICATION 1-1
1.3.1 Model Number Breakdown 1-2
1.3.2 Serial No. and Date Code Breakdown 1-2
1.4 GENERAL SPECIFICATIONS 1-2
1.4.1 Operating Environment 1-2
1.4.2 Overall Physical Dimensions 1-2
1.4.3 Vendor Weight 1-2
1.4.4 Power Requirements 1-2
1.4.5 Refrigerant Specifications 1-2
1.4.6 Coin Mechanisms and Bill Validators 1-2
1.5 VENDOR CAPACITY 1-2
1.6 PATENT DISCLOSURE 1-2
2 SAFETY 2-1
2.1 COMMITMENT TO SAFETY 2-1
2.2 SAFETY PRECAUTIONS 2-1
2.2.1 High Voltage Contact 2-1
2.2.2 Improper Grounding 2-1
2.2.3 Fan Contact 2-1
2.2.4 Helix Motion and Jamming 2-1
2.2.5 Refrigerant Release 2-1
2.2.6 Vendor Tipping 2-2
2.2.7 Other Improper Conditions 2-2
2.3 TEST STANDARDS 2-2
2.3.1 ANSI/UL 541 Refrigerated Vending Machines 2-2
2.3.2 ANSI/UL 751 Safety for Vending Machines 2-2
2.3.3 Additional Standards 2-2
3 VENDOR SYSTEMS/COMPONENTS 3-1
3.1 SENSIT II SYSTEM OPERATION 3-1
3.2 CONTROL BOARD 3-1
3.2.1 Program Chip 3-1
3.2.2 Mode Switch 3-1
3.2.3 DEX Jack 3-1
3.3 VEND SENSORS 3-1
3.3.1 Primary 3-1
3.3.2 Secondary 3-1
3.4 INTERFACE BOARD 3-2
3.5 DOOR 3-2
3.5.1 Display 3-2
3.5.2 Keypad 3-2
3.5.3 Changer Location 3-2
3.5.4 Validator/Debit Card Reader Locations 3-2
3.5.5 Coin Box 3-2
3.5.6 Door Switch 3-2
3.5.7 Coin Return Button 3-2
3.6 REFRIGERATION OPERATION 3-2
3.6.1 Refrigeration Operation 3-2
3.6.2 Temperature Control 3-2
3.6.3 Refrigeration Control 3-3
3.7 TRAY RAILS 3-3
3.8 TRAYS 3-3
3.8.1 Vend Motors 3-3
3.8.2 Helixes 3-3
3.8.3 Divider 3-3
3.8.4 Pusher Bar 3-3
3.9 ELECTRICAL PANEL 3-3
3.9.1 Transformers 3-3
3.9.2 RF Filter 3-3
3.9.3 Relay 3-3
3.9.4 Ballast 3-3
3.9.5 Power Distribution Harness 3-3
3.9.6 Ground 3-3
3.10 FUSE AND POWER SWITCH 3-3
3.10.1 Fuse 3-3
3.10.2 Power Switch 3-4
3.11 SLIDING DOOR 3-4
4 VENDOR PREPARATION AND
INSTALLATION 4-1
4.1 CONFIRMING POWER AT OUTLET 4-1
4.1.1 Checking the Outlet (US & Canada) 4-1
4.1.2 Checking the Outlet (Outside US & Canada) 4-1
4.1.3 Electrical Requirements for CE Compliance 4-1
4.1.4 Requerimiento de Servicio Eléctrico
Para Certificación CE 4-1
4.1.5 Les Utilites Electriques Necessaire
Pour Conformement Aux Regles CE 4-1
4.2 VENDOR PREPARATION 4-2
4.2.1 Inspection 4-2
4.2.2 Mounting and Connecting Bill
Validators and Card Readers 4-2
4.2.3 Mounting and Connecting Coin Mechanism 4-2
4.2.4 Determine Product Loading 4-2
4.2.5 Configuring Motors 4-2
4.2.6 Installing Price Labels 4-3
4.2.7 Setting Prices 4-3
4.3 ON-SITE INSTALLATION 4-3
4.3.1 Remove Shipping Boards 4-3
4.3.2 Placing the Vendor in Location 4-3
4.3.3 Leveling the Vendor 4-3
4.3.4 False Leg Installation 4-3
4.3.5 Initial Power-Up and Cool-down 4-4

AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
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5 TRAY ADJUSTMENT AND
CONFIGURATION 5-1
5.1 VEND TRAY 5-1
5.1.1 Removal 5-1
5.1.2 Installation 5-1
5.2 TRAY VERTICAL POSITIONS 5-1
5.2.1 Removal 5-1
5.2.2 Installation 5-1
5.3 TRAY COLUMN ADJUSTMENTS 5-1
5.4 CHANGING DIVIDERS 5-1
5.5 CHANGING HELIXES 5-2
5.6 HELIX ADAPTER 5-2
5.7 HELIX EJECTOR 5-2
5.8 HELIX ALIGNMENT DEVICE 5-2
5.9 MOTOR POSITIONS 5-2
5.10 AVOIDING PRODUCT HANG-UPS 5-2
5.11 TALL PRODUCT VENDING 5-2
5.12 PUSHER BAR INSTALLATION 5-2
6 SERVICE PROGRAMMING 6-1
SERVICE MODE 6-1
6.1 ERROR CODES 6-1
6.2 ACCOUNTING DATA 6-1
6.3 DATA LOGS 6-1
6.4 FILL/DISPENSE 6-1
6.5 DELAYED SALES 6-1
6.6 TEMPERATURE 6-2
6.7 PRICE SETTINGS 6-2
6.7.1 Set Prices 6-2
6.7.2 ValueVend 6-2
6.8 TRAY SETUP 6-3
6.8.1 Test Motors 6-3
6.8.2 Link Motors 6-3
6.8.3 Delayed Stop 6-3
6.8.4 Configure 6-3
6.9 MDB (MULTI-DROP BUS) 6-3
6.9.1 Settings 6-3
6.9.1.1 Force Vend 6-3
6.9.1.2 No Cheat 6-3
6.9.1.3 Change Bill 6-3
6.9.1.4 Hold Lost Credit 6-3
6.9.1.5 Multi-Vend 6-3
6.9.1.6 Lev2 Coin Mech 6-3
6.9.1.7 Instant Reval 6-3
6.9.1.7.1 Bill and Cash-Less Applications 6-3
6.9.1.7.2 MDB Out-Of-Service 6-4
6.9.1.7.3 Remaining in Service Without Coin Mech 6-4
6.9.1.7.4 ‘#’ Key For Escrow Return 6-4
6.9.1.7.5 Bill-Only Application Notes 6-4
6.9.1.7.6 Bill Plus Cash-Less Application Notes 6-4
6.10 OPTIONS 6-4
6.10.1 Message 6-4
6.10.2 Prize 6-4
6.10.3 Language 6-5
6.10.3.1 Primary 6-5
6.10.3.2 Secondary 6-5
6.10.3.3 Create Custom 6-5
6.10.4 Product Sensor 6-5
6.10.5 Speech 6-5
6.11 SALES BLOCKING 6-5
6.12 CLOCK SETTINGS 6-5
6.13 FREE VEND 6-5
6.14 AUXILIARY OUTPUT 6-5
6-15 PROGRAM QUICK REFERENCE 6-6
7 TROUBLESHOOTING 7-1
7.1 OUT OF SERVICE ERRORS 7-1
7.2 HEALTH AND SAFETY ERRORS 7-1
7.3 MACHINE ERROR CODES: CAUSES
AND SOLUTIONS 7-1
7.3.1 VIEWING TOP LEVEL ERROR CODES 7-1
7.3.2 VIEWING SUB-LEVEL ERROR CODES 7-1
7.3.3 ERROR CODE CHART: CAUSES
AND SOLUTIONS 7-2
7.4 CLEARING JAMMED MOTOR 7-3
7.5 ICE FORMATION IN THE CABINET 7-3
7.6 MACHINE TROUBLESHOOTING CHART 7-3
8 MAINTENANCE 8-1
8.1 REPLACING THE PROGRAM CHIP 8-1
8.2 CLEANING THE REFRIGERATION UNIT
AND SCREENS 8-1
8.3 CLEANING THE VENDOR CABINET 8-1
8.4 CLEANING THE PLASTIC DOOR LINER 8-1
8.5 CLEANING THE GLASS WINDOW 8-1
8.6 LUBRICATION WITH LITHIUM GREASE 8-2
8.7 REPLACING FLOURESCENT BULBS 8-2
8.8 DEFROSTING THE EVAPORATOR COIL 8-2
8.9 TESTING THE TEMPERATURE SYSTEM
(H & S) 8-2
8.10 PC UTILITY LOADING INSTRUCTIONS 8-2
8.10.1 Requirements 8-2
8.10.2 Installation 8-2
8.10.3 Startup 8-3
8.10.4 Toolbar 8-3
8.10.5 Program Screens 8-3
8.10.6 Software Operation 8-4
8.10.7 Shutdown 8-4
8.10.8 Errors 8-4

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
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8.11 REPLACING THE POWER CORD 8-5
8.12 STORING THE VENDOR 8.5
9 WIRING DIAGRAM 9-1
10 SUPPORTED DEX FIELDS 10-1
11 OPTIONAL EQUIPMENT 11-1
12 WARRANTY 12-1
TABLE OF FIGURES
NUMBER NAME PAGE
Figure 1.1 Vendor Serial Plate 1-2
Figure 1.2 FV Cabinet Dimensions 1-3
Figure 1.3 FV Capacity – 116 Units 1-4
Figure 1.4 FV Capacity – 120 Units 1-4
Figure 1.5 FV Helix Capacities 1-5
Figure 3.1 Control Board Components 3-1
Figure 4.1 Tip-Over Warning 4-3
Figure 4.2 False Leg Installation 4-4
Figure 5.1 Large Product Vending 5-2
Figure 5.2 Pusher Bar Installation 5-2
Figure 8.1 Replacing Control Chip 8-1
Figure 8.2 Harness, Chip Programming 8-4
Figure 8.3 Replacing The Power Cord 8-6
Figure 9.1 Typical Wiring Diagram (Sheets 1 – 4) 9-1/9-4
PUBLICATION NOTICE
L0097D, ECN 1932, 05-05-2008
It is our intent to assist our customers with up-to-date
documentation: however, this manual may not contain all updates
and is subject to revision without notice. Please contact our
Service Department with your requests or comments.

AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
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AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
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1.0 INTRODUCTION
Congratulations on the purchase of your new AMS
Sensit II vendor. All Sensit II models, including Snack, Visi-
Combo, Bottle and Food Combo, Visi-Diner and Milk, are
versatile, high-capacity vending machines. AMS machines
are designed, tested, and built to provide years of reliable,
low-maintenance service in an indoor environment. A fully
insulated cabinet, DEX data capability, and flexible product
configuration are just some of the many standard features
built into every AMS merchandiser.
See the table which follows for the capabilities of
your new vendor:
FV (FROZEN FOOD VENDOR)
CAPABILITY TEMPURATURE PROTECTION
SNACK 75°F TO 42°F
(24°C TO 5°C) NONE
REFRIGERATED
FOOD 41°F OR COLDER (5°C) H&S
SLACKED
FOOD 25°F OR COLDER (-4°C) H&S
FROZEN
FOOD 0°F OR COLDER (-18°C) H&S
1.1 SENSIT II SYSTEM
Your vendor is equipped with the Sensit II system.
The Sensit II system is a patented vend-sensing system
that detects when products fall into the delivery bin.
Basically, a plane of infra-red light is created across the top
of the delivery bin, and the Sensit II system can detect
when the light has been blocked by a falling product. Using
this technology, the vendor “knows” when your customer
gets the product. The Sensit II system has several
important benefits:
1.1.1 Guaranteed Delivery
When a product is selected the sliding door will
open and the helix will turn. If, after one revolution, the
product hangs up or an opening was missed in loading, the
helix will rotate three additional half-revolutions to make
sure the product is delivered. The sliding door will then
close. No more hitting or shaking the vendor to get
products that did not fall!
1.1.2 Instant Refund
If the customer does not receive a product, he can
receive a full refund by pressing the coin return, or he can
select another product. No more refund requests!
1.1.3 Automatic Helix Adjustment
With the Sensit II system, the helix stops as soon
as the product falls. The sliding door will close. It is no
longer necessary to adjust the home position of the helix for
each different package. In fact, different packages can be
loaded in the same column. No more double vending!
1.1.4 Additional Benefits:
1. Opening the delivery bin door will not affect the Sensit II
system. The sensors are located above the delivery bin
and will not be blocked by the bin door. Product that
falls while the door is open will still pass through the
beam.
2. Opening the door of a cold vendor will cause some
condensation to form inside. The Sensit II system will
not allow vending until this fogging clears, normally
within a few minutes of closing the door.
1.2 HEALTH AND SAFETY
1.2.1 H&S Specifications
AMS vendors intended for vending perishable food
products meet NAMA requirements for frozen food vending
machines. The NAMA specifications for frozen food product
vendors require that the temperature in the vendor must
cool to 0°F for frozen and to 25°F for slack within 75
minutes of closing the vendor door or an error will be
generated and the vendor will not allow sales. (note that
Delayed Sales has no effect on this cool-down period). This
is to allow a recovery period following loading: however, all
products should be frozen prior to loading. After the cool-
down requirement has been met, if the temperature in the
vendor exceeds 0°F for more than 15 minutes an error will
be generated and the vendor will not allow sales.
1.2.2 H&S Software
To meet these requirements, all AMS refrigerated
food vendors have control software with a built-in Health &
Safety (H&S) function. The H&S function is activated
automatically when the temperature is set to 0°F or below.
Unless otherwise specified by regulatory agencies, AMS
recommends setting the temperature to -1°F when vending
frozen food products.
1.2.3 H&S Protection
In the event the temperature exceeds the NAMA
specifications following the recovery period or during
normal operation, an error will be generated and the vendor
will not allow sales. This protects the consumer from
purchasing spoiled food. H&S error codes are detailed in
Section 7.4.
1.3 MODEL IDENTIFICATION
When requesting service, replacement parts or
technical assistance, please refer to the vendor Serial Plate
(refer to Figure 1.1). It is attached inside the door near the
upper right corner of the window and is visible from the
outside. The information contained on this plate is
necessary to determine what parts, kits, or maintenance
should be applied to your specific model.

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
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Figure 1.1 Vendor Serial Plate
1.3.1 Model Number Breakdown (refer to Figure 1.1)
AMS 39 - 6 40
Manufacturer Cabinet Number of Number of
Width Trays * Selections*
1.3.2 Serial Number and Date Code Breakdown
(refer to Figure 1.1)
Sequential Production Number
1234 1678 28
Production Run Number Quarter (1234) Year
Example: 1234-1678-28 would be translated as sequence
number 1234 of production run 1678, manufactured in the
second quarter “2” of 2008.
The Production Run Number of machines built in
the U.S. starts with the number 1 or any odd number. The
Sequential Production Number of machines built in Mexico
starts with the number 0 or any even number.
1.4 GENERAL SPECIFICATIONS
1.4.1 Operating Environment
AMS vendors are designed for indoor use only.
Indoor temperatures must be between 45°F (7°C) and
110°F (43°C). Maximum temperature for vendors with
perishable food is 100°F (38°C). The vendor should not be
located in an area where it may be subjected to a water jet
or rain.
1.4.2 Cabinet Physical Dimensions (refer to Figure 1.2):
39”W x 72”H x 36”D (99 cm x 183 cm x 91 cm)
1.4.3 Vendor Weight:
Approx. 738 lbs. (335 kg)
1.4.4 Power Requirements:
United States,
Canada and Mexico: 115 VAC, 60 Hz
International: 230 VAC, 50/60 Hz
Frozen Food (FV) 10.8 amps @115 VAC (1242 watts)
5.6 amps @220 VAC (1242 watts)
1.4.5 Refrigerant Specifications:
¾ HP, R-404A, 19.5 oz. (.55 kg)
1.4.6 Coin Mechanisms and Bill Validators
AMS vendors will support all NAMA-approved
Multi-Drop Bus (MDB) coin mechanisms, bill validators and
card readers. Where applicable, it will also support the
“Executive Mechanism” Coin Changer.
1.5 VENDOR CAPACITY:
Capacity depends on configuration (refer to
Figures 1.3, 1.4 and 1.5 on the following pages)
1.6 PATENT DISCLOSURE
This vendor and/or certain of its components are
covered by one or more of the following U.S. and
International patents;
U.S. 6,041,962
6,145,699
6,202,888
6,384,402
6,520,373
6,708,079
6,794,634
7,191,915
7,246,719
7,343,220 B2
Canada 2,329,314
Mexico 230714

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
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Figure 1.2 FV Cabinet Dimensions
(For Reference Only)

AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
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5 5 5 5
5 5 5 5
5 5 5 5
7 7 7 7
7 7 7 7
FV - 116 UNITS
Figure 1.3 FV CAPACITY - 116 UNITS
5 5 5 5
7 7 7 7
6 6 6 6
6 6 6 6
6 6 6 6
FV - 120 UNITS
Figure 1.4 FV CAPACITY - 120 UNITS

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
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Available Helix Sizes:
Name P/N Pitch Slot Opening Note
22518-04 4 Pitch 3.46” (87.8mm)
22518-05 5 Pitch 2.91” (73.9mm)
22518-07 7 Pitch 2.2” (55.8mm)
22518-09 9 Pitch 1.77” (44.9mm)
3.75 Inch (95.2mm)
Counter-Clockwise
22518-11 11 Pitch 1.48” (37.6mm)
22519-04 4 Pitch 3.46” (87.8mm)
22519-05 5 Pitch 2.91” (73.9mm)
22519-07 7 Pitch 2.2” (55.8mm)
22519-09 9 Pitch 1.77” (44.9mm)
2.6 Inch (66mm)
Counter-Clockwise
22519-11 11 Pitch 1.48” (37.6mm)
22520-04 4 Pitch 3.46” (87.8mm) Use with 22519-04
22520-05 5 Pitch 2.91” (73.9mm) Use with 22519-05
22520-07 7 Pitch 2.2” (55.8mm) Use with 22519-07
22520-09 9 Pitch 1.77” (44.9mm) Use with 22519-09
2.6 Inch (66mm)
Clockwise
(See Note) 22520-11 11 Pitch 1.48” (37.6mm) Use with 22519-11
NOTE: Pair clockwise helixes with counter-clockwise helixes of the same pitch when using dual helix motors.
Figure 1.5 FV HELIX CAPACITIES

AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
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2.0 SAFETY
2.1 COMMITMENT TO SAFETY
Automated Merchandising Systems Inc. is
committed to designing and producing a safe product. As
with all electrical or mechanical pieces of equipment,
potential hazards exist. It is the intent of Automated
Merchandising Systems, through this manual and service
technician training, to alert individuals who will be servicing
our equipment to these potential hazards, and to provide
basic safety guidelines.
To reduce the risk of serious injury or death,
please read and follow all warnings in this manual. It is
important that we point out that these warnings are not
comprehensive. Automated Merchandising Systems can
not possibly anticipate all of the ways that service may be
conducted, nor all of the possible safety hazards that may
result from such service. Therefore at all times we urge
you to beware of hazards such as electrical shock,
mechanical entrapment, and tipping a vendor during
movement.
Automated Merchandising Systems strongly
recommends a commitment to safety on the part of all
servicing personnel or organizations. Only personnel
properly trained in vendor servicing should attempt any
service to the internal components of the vendor. It is
important to point out that Automated Merchandising
Systems has no control over the vendor once it leaves our
factory. Maintaining the vendor in a safe condition is
the sole responsibility of the owner.
If you have questions concerning safety or service,
or would like more information, please contact the
Automated Merchandising Systems Service Department at
304-725-6921 or e-mail [email protected].
2.2 SAFETY PRECAUTIONS
Below are listed safety precautions and safe
practices to follow to avoid injury from selected hazards.
This list can not possibly cover all hazards, therefore please
remember to THINK SAFETY FIRST.
2.2.1 High Voltage Contact
Each vendor is designed to operate on a specific
voltage, either single phase 115VAC 60Hz or 220-240VAC
50-60Hz, depending on the country. The voltage is
specified on the serial plate (refer to Section 1.3 Model
Identification). High voltage areas include the electrical
panel, the refrigeration unit and fans, and the fluorescent
lamps. It is important to understand that contact with the
high voltage wiring can result in injury or death.
1. Always test the outlet for proper voltage, polarity and
grounding before plugging in the vendor.
2. Always disconnect power to the vendor before
servicing. Allow only fully trained service technicians
to service the vendor if service must be performed with
the power on.
3. Always keep electrical connections dry. Do not place
the vendor in or near standing water.
4. Never use a worn or damaged power cord.
2.2.2 Improper Grounding
Some electrical components have a green or
green/yellow ground wire attached to a grounding point in
the vendor. If it becomes necessary to remove a ground
wire during service, note how the wire is attached, including
the locations of any washers. After servicing, make sure
that the wires and washers are replaced exactly as they
were. Note that the vendor may appear to work normally
without the ground wires, but there will be a potential shock
hazard from ungrounded components.
1. Always test the outlet for proper grounding before
plugging in the vendor.
2. Always reconnect ground wires after servicing.
3. Test the ground fault circuit interrupter (GFCI)
periodically to insure proper operation.
2.2.3 Fan Contact
The vendor refrigeration unit is equipped with
electric fans which can start automatically. These fans are
enclosed to prevent accidental contact. The electrical
power must be disconnected before removing the unit from
the vendor.
1. Always disconnect power to the vendor before
servicing.
2. Always keep covers in place.
3. Always wear hand and eye protection when servicing
the vendor.
4. Always keep hair and loose clothing tied back.
5. Never insert hands or tools into concealed areas.
2.2.4 Helix Motion and Jamming
Energized vend motors can turn a helix with
considerable torque, creating a possible entrapment
hazard. Also, turning helixes may eject tools or other
objects left on trays. A helix that is jammed or caught can
store energy as it binds, which can cause it to twist or
spring outward suddenly even if power is disconnected.
Use caution when freeing a jammed helix.
1. Always disconnect power to the vendor or control
board before servicing the vend motors.
2. Always check for proper fit when loading products in
helixes to avoid jamming.
3. Always restrain the helix before freeing a jammed or
caught helix.
4. Always wear hand and eye protection when servicing
the vendor.
5. Always keep hands, hair, loose clothing and tools away
from moving parts.
2.2.5 Refrigerant Release
It should also be noted that releasing refrigerant to
the atmosphere is a federal crime and is punishable by law.
Any service work requiring the system to be opened must
be performed by a licensed technician using certified
equipment. Unauthorized service to the sealed refrigerant
system may void the warranty.

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
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The refrigeration system is pressurized and sealed
at the factory. Puncturing or cutting any component in the
system will cause refrigerant gas and liquid to be propelled
out of the system, creating an immediate physical hazard.
Use caution to avoid accidentally opening the refrigerant
system.
1. Never puncture or cut any component in the
refrigeration system.
2. Always use licensed service technicians to service the
refrigeration system.
3. Always wear hand and eye protection when servicing
the vendor.
2.2.6 Vendor Tipping
The empty weight of the vendor is approximately
800 pounds. A falling vendor can cause serious injury or
death. Caution should always be taken to avoid dropping
or tipping a vendor.
1. Never rock or tip the vendor. It must be kept upright for
safe operation.
2. Never place the vendor in an inclined position, such as
on a ramp or with all the legs not on the same horizontal
surface.
3. Never place the vendor in a moving environment such
as on a ship without properly securing it in place.
4. Never place the vendor in a location where it may be
struck by a vehicle.
5. Never transport an unsecured vendor.
6. Never attempt to lift or move the vendor by hand.
7. Always use lifting equipment with the proper load rating.
Note that the Specification weight listed is empty weight.
2.2.7 Other Improper Conditions
Hazardous conditions can be created by improper
use or service of the vendor.
WARNING: Do not use electrical appliances, including
heaters, inside the vendor.
1. Always reinstall all parts removed during service to
their original locations, including screws, bolts and
other fasteners.
2. Never make unauthorized modifications to any part of
the vendor.
3. Always replace components that are worn, broken, or
otherwise unfit for use.
4. Never use unauthorized parts, or use parts for anything
other than their intended application.
2.3 TEST STANDARDS
AMS vending machines bearing the ETL mark have
been tested and comply with one of the following
standards:
2.3.1 Standard for Refrigerated Vending Machines
ANSI/UL 541and the Standard for Refrigeration
Equipment, CAN/CSA C22.2 No. 120
2.3.2 Standard for Safety for Vending Machines ANSI/UL
751 and the Standard for Vending Machines,
Consumer and Commercial Products (CAN/CSA
C22.2 No. 128
2.3.3 Additional Standards
Certain models comply with the following:
2.3.3.1 European Union
European Economic Area
CE (European Conformity)
2.3.3.2 2007 Appliance Efficiency Regulations
CEC-400-2007-016-REV1
2.3.3.3 Natural Resources Canada (NRCan)
Energy Efficiency Regulations, OEE

AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
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3.0 VENDOR SYSTEMS AND COMPONENTS
3.1 SENSIT II SYSTEM OPERATION
1. The Sensit II system is comprised of the control logic
board, the interface board, the primary sensor, and the
secondary sensor. Both primary and secondary sensor
boards contain infra-red emitters and detectors. When
installed at the ends of the delivery bin, the emitter on
one board at one end is being detected by the detectors
on the board on the opposite end. The control board
controls the performance of the vending operation.
2. When a selection is made, the interface board will open
the sliding door. The column motor will begin to run.
After several seconds, if no product falls in the hopper,
the motor will be stopped, the sliding door will close, the
credit will be maintained and the customer will be
directed to “PLEASE MAKE ANOTHER SELECTION.”
3. When the controller measures a variation in the light
intensity during the vend cycle, it recognizes that a
product has fallen through the light into the hopper. The
interface board will close the sliding door, the controller
will stop the vend motor and the credit is removed.
4. When the vendor door is opened for loading or service,
the clear lens on the sensor protective cover can
become fogged up, particularly in hot or humid
locations. In these cases, the vendor will display
“SENSIT BLOCKED – UNABLE TO VEND” until the
fogging has cleared, usually within minutes after closing
the door.
3.2 CONTROL BOARD
The control board contains a program chip which
controls and monitors the vendor, DEX, and the mode
switch used to enter service mode. The control board is
located in the upper left hand corner of the open vendor
door, behind an access door. See Figure 3.1.
3.2.1 Program Chip
The program chip contains the software that controls
vending and refrigeration (refer to Figure 3.1). The
software can be upgraded by replacing the chip or by
uploading new software through the DEX plug , but please
note that all settings such as pricing and motor
configuration will have to be reprogrammed. Refer to
Section 8.0 for replacing the control chip or software.
3.2.2 Mode Switch
Pressing the mode switch (refer to Figure 3.1)
switches from vend mode to service mode. Use service
mode to change settings, access vend data, and check
error codes for troubleshooting. Data is displayed on the
front display panel, and is entered entered at the front
selection panel. Pressing the switch again or simply closing
the vendor door will automatically switch the control board
to vend mode.
Figure 3.1 Control Board Components
3.2.3 DEX Jack
The DEX jack (refer to Figure 3.1) is provided for
downloading detailed vend data and uploading new control
board software.
3.3 VEND SENSORS
3.3.1 Primary Sensor
The primary sensor is located on the left of the
delivery bin when viewing the back of the door. The
primary sensor, inside a protective cover, receives the light
emitted from the secondary sensor and sends a signal to
the control board based on the intensity of the beam. When
a product drops into the delivery bin, it causes a change in
light intensity which is interpreted by the control as a
successful vend.
When servicing the primary sensor be mindful of the
emitter and the black detector cells along the top of the
board. These can be knocked out of alignment or
damaged by rough handling.
The primary and secondary sensors function in an
identical fashion: however, the primary board incorporates
various connectionor for temperature, control, and
secondary sensor harnesses.
If a product sensor is used, the sensor on the left
end connects to the primary sensor with a single small
harness.
3.3.2 Secondary Sensor
The secondary sensor is located on the right end of
the delivery bin when viewing the back of the door. The
secondary sensor, inside a protective cover, receives the
light emitted from the primary sensor and sends a signal to
the control board based on the intensity of the beam. When
a product drops into the delivery bin, it causes a change in
light intensity which is interpreted by the control as a
successful vend.
When servicing the secondary sensor be mindful of
the emitter and the black detector cells along the top of the

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
3-2
board. These can be knocked out of alignment or
damaged by rough handling.
The primary and secondary sensors function in an
identical fashion: however, the secondary board is
connected to the primary by a single harness.
If a product sensor is used, the sensor on the right
end connects to the secondary sensor with a single small
harness.
3.4 INTERFACE BOARD
The interface board is mounted inside the right rail
mount, behind the steel panel.
The interface board is an input/output device under the
control of the control board.
The interface board controls the sliding door, the
defrost functions and the evaporator fan motor.
3.5 DOOR
3.5.1 Display
The display is located on the front of the door. It serves
as the interface for using and programming the machine. In
service mode, it displays the active function and parameter
values. In vend mode it can display the selection entered,
the price of a selected item and the credit accumulated.
When the machine is idle it can display the time and a
scrolling message.
When the asterisk key is pressed the display also
indicates the chiller status, shown in the lower right corner
of the temperature display.
- = Chiller off due to open door
V = Chiller off due to low voltage
D = Chiller off due to defrost timer
P = Chiller off due to pressure timer
% = Chiller can run, subject to temperature
set-point and EnergySENSIT
The number displayed before the % sign indicates the
% of time the compressor has been running in the previous
4 hours.
In case of multiple reasons for a chiller not running the
display will show the foremost reason listed (i.e., door open
takes precedence over low voltage).
3.5.2 Keypad
The keypad is located below the display on the front of
the door. A vending selection is made by keying in the
number combination that corresponds to the location of an
item in the machine. The keypad is also used to enter data
when the vendor is in service mode.
3.5.3 Changer Location
Three screws are installed just below the coin chute.
These screws mate to the keyhole slots on the back of the
changer. Refer to Section 4.2.4 Mounting And Connecting
Coin Mechanism.
3.5.4 Validator & Debit Card Reader Locations
There are two locations that will accept bill validators
and debit card readers The lower position meets the
guidelines of the Americans with Disabilities Act (ADA) for
access by handicapped persons. Refer to Section 4.2.3
Mounting and Connecting Bill Validators and Card Readers
3.5.5 Coin Box
The coin box is located below the changer, behind a
separate door, and is used to hold overflow coins when the
changer is full. It is removed by tilting slightly and lifting
out.
3.5.6 Door Switch
The door switch is mounted on the back of the door.
The control uses the door switch to turn off the refrigeration
unit when the door is open, and to switch from service
mode to vend mode when the door is closed.
3.5.7 Coin Return Button
The coin return button is located next to the coin slot.
Pressing the coin return button will release bent or irregular
coins that are not accepted by the changer. If the machine
fails to vend a selection that has been made, pressing the
coin return will return the full credit. If the Force Vend
option is disabled, it can also return the full credit before a
selection is made. If the Bill Changer option is enabled, the
coin return will return change for bills inserted in the bill
validator.
3.6 REFRIGERATION SYSTEM
3.6.1 Refrigeration Operation
The compressor compresses refrigerant gas, which
increases the pressure and temperature of the gas. As the
hot, compressed gas passes through the fan-cooled
condenser, it is cooled and condenses to a liquid. This fan
draws outside air in through a vent in the door bottom,
through the condenser where it removes the heat and is
blown out through a vent in the back of the cabinet. This
part of the refrigeration system is insulated from the
refrigerated part of the cabinet.
Driven by the pressurized gas entering the condenser,
the liquid passes through a desiccant dryer and a thermal
expansion valve. The thermal expansion valve controls the
rate at which the liquid refrigerant enters the evaporator.
Lower pressure in the evaporator allows the liquid to
evaporate, which lowers its temperature. An evaporator fan
forces air from the refrigerated part of the cabinet across
the evaporator, where the air is cooled by transferring heat
to the refrigerant. The cooled air is returned to the
refrigerated part of the cabinet.
The warmed gaseous refrigerant is then sucked from
the evaporator through an accumulator, which traps any
liquid refrigerant and allows it to evaporate before entering
the compressor. The refrigerant is then sucked into the
compressor to be compressed, completing the cycle.
3.6.2 Temperature Control
The evaporator fan runs continuously to circulate
cooling air within the cabinet. A temperature sensor
located near the evaporator measures the temperature of
air entering the evaporator. When this temperature is
above the temperature setting in the control, the
compressor and condenser fan are turned on.
When the temperature falls to 5°F below the
adjustable temperature setpoint, the compressor and
condenser fan are turned off. Refer to Section 6.6 for
setting the temperature setpoint.

AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
3-3
3.6.3 Refrigeration Control
1. The refrigeration system is operated through the control
board. A temperature sensor in the cabinet relays the
current temperature to the control.
2. If the temperature is above the setting that has been
programmed in by the user, the control sends a 24VDC
signal to the refrigeration relay. The energized relay
closes to complete the high voltage circuit that powers
the compressor and the condenser fan.
3. If the compressor should overheat, a thermal overload
removes power to the compressor until it has cooled.
4. The defrost interval can be programmed for 3 to 12
hours, in 1 hour increments. The recommended factory
default setting is 3 hours. The entire cycle lasts
approximately 14 minutes and the cabinet temperature
will rise slightly during this time.
5. When the temperature in the cabinet reaches 5°F cooler
than the temperature setting, the control de-energizes
the relay breaking the circuit powering the compressor.
6. The control will also shut off the compressor if the door
is opened. This is to prevent the evaporator from
freezing up after drawing in excessive moisture-laden
air.
7. After the compressor has shut down, the control will wait
until the compressor has been shut down 15 seconds
before restarting the compressor. The delay allows
pressure in the system to equalize.
3.7 TRAY RAILS
The rails are located inside the cabinet and are used to
support the trays. The rails are adjustable up and down in
1” increments. Refer to Section 5.2 Tray Vertical Positions.
3.8 TRAYS
3.8.1 Vend Motors
The vend motors are snapped into mounting holes on
the back of each tray. Each column has one vend motor
which is driven by 24 VDC from the control board. These
motors do not have a home position switch. They will stop
when the sensor has detected a vend, whether the rotation
has been more or less than 360°. Refer to Section 4.2.6
and Section 5.11.
3.8.2 Helixes
There are two sizes of helixes in a vendor,
approximately 2.6” and 3.7” in diameter. There are several
pitches available in each size. The pitch is determined by
counting the number of product openings in the helix. Refer
to Figure 1.5 Helix Capacities.
3.8.3 Divider
The divider separates product columns on the tray.
Two horizontal slots in the divider allow for the installation
of a pusher bar. To remove the divider, push rearward and
lift. To install, insert the rear tab in the desired slot, push
rearward and then down. Make sure the locking tabs on
the bottom have engaged their respective slots and pull
forward.
3.8.4 Pusher Bar
The pusher bar keeps products pushed to one side of
the column. This is typically used with tall products. The
pusher bar is removed by pulling the bar free from the
plastic clips. To reinstall, it is easiest to press the bar into
the clip using pliers. Refer to Section 5.16 Pusher Bar
Installation.
3.9 ELECTRICAL PANEL
The electrical panel is located in the recess formed by
the right rail mount on the right side of the cabinet, behind
an access panel.
3.9.1 Transformer
The transformer reduces the input voltage to 24 volts
AC for the control board.
A second transformer reduces the input voltage to 24
volts AC for the window heater.
3.9.2 RF Filter
The filter removes electrical noise from the power
supplied to the 24VAC transformer to prevent interference
with operation of the control board and software.
3.9.3 Relay
Three relays are used, the evaporator fan relay, the
defrost element relay and the chiller unit relay. All are
controlled by 24 VDC signals from the control board to
close the relay and supply high voltage to the specified
component. The fan relay is mounted inside the right rail
mount. The other two are mounted on the chiller unit.
3.9.4 Ballast
The ballast provides the necessary power to the
fluorescent lamps in the door.
3.9.5 Power Distribution Harness
The power distribution harness splits the incoming
power into individual leads for the high voltage
components.
3.9.6 Ground
Ground is made through the use of grounding studs or
screws at the lower back wall of the right mount. Earth
ground and individual ground wires from the high voltage
components are attached here.
3.10 ELECTRICAL FUSE AND POWER SWITCH
The fuse and switch are located at the bottom of the
right rail mount.
3.10.1 Fuse
The fuse contains a 3AG fast-blow fuse to protect the
24 VAC power supply to the control board. A spare fuse is
also located inside the front of the fuse holder. The fuse
holder is opened by pressing down on the indicated side
and pulling out.

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
3-4
3.10.2 Power Switch
The power switch is used to disconnect power to the
control board. The switch should be used to shut off power
before MDB devices are being connected or disconnected,
before the control board is being serviced, or before any
wiring harness is connected or disconnected.
Unplug the power cord to remove the vendor from all
electrical power.
3.11 SLIDING DOOR
The sliding door is located under the bottom-most tray
and is used to seal off the space between the cabinet and
door of the vendor.
When a selection is made, the sliding door will move
back, allowing the selection to fall thru the sensors and into
the hopper. The sliding door will then move forward against
the vendor door to seal off the vendor.
The motor which moves the sliding door is controlled
by the interface board.
The seals on all sides of the sliding door have been
designed to preserve the temperature inside the vendor
when the sliding door is closed.

AMS SENSIT II FROZEN FOOD VENDOR L0097 Rev. D
4-1
4.0 VENDOR PREPARATION AND INSTALLATION
Setting up a vendor has been divided into three
stages. Step 4.1 confirms power availability at the site
where the vendor is to be located. Step 4.2 is vendor
preparation accomplished in the shop. Step 4.3 is
accomplished on-site when the vendor is installed.
4.1 CONFIRMING POWER AT OUTLET
4.1.1 Checking the Outlet (US and Canada)
AMS recommends using a dedicated outlet which
can supply 15 to 20 amps per vendor.
Using a volt meter set to AC VOLTS, check the
voltage between the positive (smaller) lug entry and the
ground lug entry (or center screw on two-lug outlets). The
reading should be between 103 volts and 126 volts.
Next, check the voltage between the negative (larger) lug
entry and the ground. The reading should be 0 volts. If
your results vary, contact a qualified electrician to correct
the outlet wiring before plugging in the vendor. Abnormal
voltage, reversed polarity or improper grounding may
cause the vendor to malfunction or create hazardous
conditions in the vendor, resulting in possible injury,
damage to the vendor, or fire.
The power cord is shipped in the hopper on the
inside of the door. The cord is supplied with a standard
NEMA 3-wire plug. If there are no 3-wire outlets available
for powering the vendor, a grounding adapter may be used
to convert a 2-wire outlet to accept the 3-wire plug. The
adapter must have a ground tab or wire which must be
fastened to the center screw of the outlet. . When the
adapter is installed in the outlet recheck voltage as given
above for 103 to 126 volts and also as given above for 0
volts. NEVER USE AN EXTENSION CORD
WITH THE VENDOR.
4.1.2 Checking the Outlet (Outside the US and
Canada)
Consult a qualified electrician to check the outlet for
proper polarity, voltage, and grounding. Check the serial
plate on the side of the door to confirm the vendor is rated
for the outlet voltage.
4.1.3 Electrical Service Requirement for CE
Compliance
The following requirement applies only to models
using ½ HP compressors and displaying the CE mark on
the serial plate. If this requirement applies to your vendor,
you will see a similarly worded decal on the back of the
vendor near the power cord. This requirement does not
apply to any vendor using 120V service.
ELECTRICAL SERVICE REQUIREMENT FOR CE
COMPLIANCE:
THIS EQUIPMENT IS INTENDED FOR USE ONLY IN
PREMISES HAVING A SERVICE CURRENT CAPACITY
OF AT LEAST 100A PER PHASE, SUPPLIED FROM A
DISTRIBUTION NETWORK HAVING A NOMINAL
VOLTAGE OF 400/230V. THE USER SHOULD
DETERMINE IN CONSULTATION WITH THE SUPPLY
AUTHORITY, IF NECESSARY, THAT THE SERVICE
CURRENT CAPACITY AT THE INTERFACE POINT IS
SUFFICIENT FOR THIS EQUIPMENT.
4.1.4 Requerimiento de Servicio Eléctrico para
Certificación CE
El siguiente requerimiento se aplica solamente a
los modelo utilicen compresores de ½ HP y que muestren
la marca CE en la placa de serie. Si este requerimiento se
aplica a su dispensadora, verá una calcomanía con una
terminología parecida en la parte posterior de la
dispensadora, cerca del cordón de corriente.
Este requerimiento no se aplica a dispensadoras
que utilizan un servicio de 120V.
REQUERIMIENTO DE SERVICIO ELECTRICO PARA
CERTIFICACION CE:
ESTE EQUIPO SE PUEDE UTILIZAR SOLAMENTE EN
ESTABLECIMIENTOS QUE CONTENGAN UNA
CAPACIDAD DE CORRIENTE DE SERVICIO DE POR LO
MENOS 100A POR FASE, Y SUMINISTRADOS POR UNA
RED DE DISTRIBUCION QUE CONTENGA UN VOLTAJE
NOMINAL DE 400/230V. EL USUARIO DEBERA
CONSULTAR CON UNA AUTORIDAD DE SUMINISTRO,
SI ES NECESARIO, PARA VERIFICAR QUE LA
CAPACIDAD DE CORRIENTE DE SERVICIO EN EL
PUNTO DE INTERFASE ES SUFICIENTE PARA ESTE
EQUIPO.
4.1.5 Les Utilites Electriques Necessaire Pour
Conformement Aux Regles CE
Le suivant condition applique seulement à modèle
en utilisant ½ HP compresseur et montrer le CE sur l'en
série plaque. Si cette condition s'applique à votre vendeur,
vous verrez un decal de même exprimé sur le dos du
vendeur près du cordon d'alimentation.
Cette condition ne s'applique pas au service de
120V d'utilisation de vendeur.
LES UTILITES ELECTRIQUES NECESSAIRE POUR
CONFORMEMENT
AUX REGLES CE:
CET EQUIPEMENT NE DOIT UTILISER QUE SUR LES
LIEUX AVEC UNE CAPACITE DU COURANT AU MOINS
100A LA PHASE, FOURNIE A UN RESEAU DE
DISTRIBUTION AVEC UN VOLTAGE NOMINAL DE
400/230V. LA PERSONNE QUI SE DETERMINER
PENDANT UNE CONSULTATION AVEC
L’ADMINISTRATION DU SECTEUR, S’IL FAUT, QUE LA
CAPACITE DE COURANT AU POINT D’INTERFACE EST
ASSEZ POUR CET EQUIPEMENT.

L0097, Rev. D AMS SENSIT II FROZEN FOOD VENDOR
4-2
4.2 VENDOR PREPARATION
4.2.1 Inspection
Inspect the vendor carefully for shipping damage
prior to signing the carrier’s delivery receipt. Check for
dents on the top or sides of the vendor, bent legs, broken
glass, or other damage on the exterior of the machine.
Check the interior for components that may have been
knocked loose or other damage.
4.2.2 Mounting and Connecting Bill Validators and
Card Readers
The AMS vendor will support any NAMA-approved
Multi-Drop Bus (MDB) bill validator or card reader. Please
read the device manufacturer’s literature before
proceeding.
WARNING: Always disconnect power to the control
board before servicing.
1. On the inside of the main door, locate and open the
access doors on the left side. Locate the white plastic
coin chute which leads from the coin slot on the front
of the door. Above the coin chute are (2) metal
plates, each fastened to a set of (4) threaded
mounting studs which correspond to the mounting
holes in the bill validator. Either set of mounting studs
may be used for a bill validator or card reader. The
lower mounting position is ADA approved for
consumers with disabilities.
2. Remove the four nuts that retain the steel cover
panel. Remove the steel cover panel, then press out
the plastic cover panel in the escutcheon.
3. Refer to the manufacturer’s literature for instructions
on accessing the mounting holes in your device.
Place the mounting holes over the threaded studs
and reinstall the nuts. Some devices may require
spacers, which are available from AMS (Part Number
20258).
4. Connect the wiring harness to the MDB harness from
the control board. If two devices are installed,
connect the second device to the validator.
5. If a coin mechanism has been previously installed,
disconnect it from the control board MDB harness and
connect it to the validator or second device if
installed.
6. Reconnect power to the control board.
4.2.3 Mounting and Connecting Coin Mechanism
(Changer)
The AMS vendor will support any NAMA-approved
Multi-Drop Bus (MDB) Coin Mechanism. On some export
models, the Mars-type Executive Mechanism is supported.
Please read the coin mechanism manufacturer’s literature
before proceeding.
Warning: Always disconnect power to the control
board before servicing.
1. On the inside of the main door, locate and open the
access doors on the left side. Locate the white plastic
coin chute which leads from the coin slot on the front
of the door. Below the coin chute are (3) screws
which correspond to slots on the back of the changer.
Do not remove these screws.
2. Install the changer by placing the large round opening
at the bottom of each slot over a screw head. Be
careful to hold the wiring harnesses in this area out of
the way. Once each of the round openings are over
the screw heads, the changer is lowered to engage
the narrow portion of the slot with the shank of each
screw (if the screws are short, back out each screw
by ¼ turn and retry mounting the changer).
3. Tighten the mounting screws (reference
manufacturer’s literature).
4. Connect the wiring harness to the bill validator (if
applicable) or to the MDB connector from the control
board.
5. Adjust the white plastic coin chute as required to align
the chute with the changer.
6. Reconnect power to the control board.
4.2.4 Determining Product Loading
Before putting the vendor on location, it is a good
idea to determine the placement of products on the trays.
Place at least one product in each helix to check for fit.
1. Remove the cardboard spacers and ties securing the
trays.
2. Refer to Section 5.3 for tray vertical adjustments, and
Section 5.4 for tray column configuration when
configuring your vendor to suit your product.
3. Make sure the product can slide in and out of the helix
easily. If the product is too snug, it may cause the
helix to jam during vending. Place it in a helix with a
larger opening.
4. Likewise, if the product is too loose in the helix, it may
not vend properly. Use a helix with the smallest
opening that will allow the product to slide in and out
freely. Refer to Sections 5.6 and 5.7.
5. Place tall, narrow products in a column with a pusher
bar, which is an adjustable bar used to push the
product to one side of the column.
6. Make sure there is adequate clearance between the
tops of the packages and the trays above when sliding
the trays in and out, and when the product is being
vended.
7. This is also a good time to set the position of the helix
to make sure the first product is held securely in the
helix. To do this, vend a product from each column.
The end position of the helix will automatically be set to
this position when a product is vended. The control
stops the helix the instant the sensor detects a product
falling in the hopper.
8. If desired, the position of the other helixes can be set
manually by pulling the helix out of the motor, rotating it
to the same position as the first helix, and reinserting it
in the motor. Note that this position is automatically
set after each vend.
9. Test vend the product and add a helix ejector if
necessary. The helix ejector is a plastic device
installed on the front end of the helix to kick out the
product (refer to Section 5.9 Helix Ejector).
4.2.5 Configuring Motors
You will need to configure the motors if you have
changed the arrangement or number of motors.
1. Press the mode switch on the control board (refer to
Figure 3.1, or the decal inside the access door, for the
location of the mode switch).