Amron 8211 User manual

Instruction Manual
for
Amron International, Inc.
Model 8211
Compact 2-Diver SCU Air Control System
S/N:
1380 Aspen Way, Vista California 92081-8349
United States of America
Phone: [phone]
Fax [phone]
email: [e-mail]
web: www.amronintl.com
This manual and the information contained herein are provided for use as an operation and
maintenance guide. No license or rights to manufacture, reproduce, or sell either the manual or
articles described herein are given. Amron International, Inc. reserves the right to change
specifications without notice.
Copyright© 2016 Amron International, Inc.

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TABLE OF CONTENTS
1. INTRODUCTION AND SPECIFICATIONS ..........................................................................................1
1.1 Introduction....................................................................................................................................1
1.2 Air Control Specifications..............................................................................................................3
1.3 Depth Monitoring (Pneumo) Gauge Specifications.......................................................................4
1.4 Communications Specifications....................................................................................................4
1.5 Enclosure Specifications...............................................................................................................5
2. WARRANTY & SERVICE POLICY .....................................................................................................6
2.1 Limited Warranty ..............................................................................................................................6
2.2 Service Policy...................................................................................................................................6
3. OPTIONS AND ACCESSORIES.........................................................................................................7
3.1 Model /28A –Wireless Tender Option..........................................................................................7
3.2 Amron Heavy-Duty Headset - Model 2401-28..............................................................................7
3.3 Amron Standard Headset - Model 2460-28 ..................................................................................7
3.4 Amron Push-to-Talk Microphone - Model 2405-28.......................................................................7
3.5 Amron Remote Walk-and-Talk Module 2822-28...........................................................................7
3.6 Amron Remote Push-to-Talk Module - Model 2821-28 ................................................................7
3.7 Amron Wireless Tender Headset –Model 2829-11......................................................................7
3.8 DIN Adapter 300 Bar - Amron Part Number HAS-300D...............................................................7
4. SAFETY AND REGULATIONS ..........................................................................................................8
4.1 Diving Safety and Regulations......................................................................................................8
4.2 Personnel Requirements...............................................................................................................9
4.3 Air Supply Requirements ..............................................................................................................9
4.4 Calibration, Service and Inspection ............................................................................................10
5. CONTROLS & CONNECTIONS ...................................................................................................... 11
5.1 Air Control ...................................................................................................................................11
5.2 Depth Monitoring.........................................................................................................................13
5.3 Air Control Front Panel - Communications, Model 8211 ............................................................14
5.4 Communications .........................................................................................................................15
5.5 Communicator Front Panel, Model 2825A-8211.........................................................................19
6. PRE-DIVE PROCEDURES ..............................................................................................................20
6.1 Pre-Dive Set-Up..........................................................................................................................20
6.2 Pre-Dive Check Out ....................................................................................................................20
6.3 Pre-Dive Pneumo Test................................................................................................................21
6.4 Pre-Dive Testing Communications..............................................................................................22
6.5 Connecting Diver Umbilical.........................................................................................................22
6.6 Low Pressure Supply ..................................................................................................................22

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7. OPERATING PROCEDURES ..........................................................................................................23
7.1 Low Pressure Breathing Air (Primary Supply) ............................................................................23
7.2 High Pressure Breathing Air (Primary Supply)............................................................................23
7.3 Pre-Operation Checklist..............................................................................................................24
7.4 Pneumo Readings.......................................................................................................................25
7.5 Diver Communications................................................................................................................26
7.6 2-Wire Operation (Refer to Figure 3) ..........................................................................................26
7.7 Diagram, Set-Up Instructions (Figure 3) .....................................................................................28
7.8 FULL DUPLEX (4-Wire) Operation (Refer to Figure 4) ..............................................................29
7.9 Diagram, FULL DUPLEX 4-Wire connection Model 2825-8225 (Figure 4) ................................30
7.10 FULL DUPLEX What, Why and How?........................................................................................31
7.11 To Operate and/or Check Out FULL DUPLEX ...........................................................................35
8. THEORY OF OPERATION .............................................................................................................36
8.1 Mechanical..................................................................................................................................36
9. MAINTENANCE .......................................................................................................................... 39
9.1 Review of Scheduled Maintenance.............................................................................................39
9.2 Air Control Scheduled Maintenance ...........................................................................................39
Complete the above tests plus the following...........................................................................................40
10. TROUBLESHOOTING AND REPAIR ...............................................................................................41
10.1 General Information ....................................................................................................................41
10.2 Air Control ...................................................................................................................................41
10.3 Depth Monitoring.........................................................................................................................44
10.4 Diver Communications................................................................................................................44
11.REFERENCE MATERIAL................................................................................................................49
11.1 Diving Log, U.S Navy (Chart)......................................................................................................49
11.2 Repetitive Dive Worksheet..........................................................................................................50
11.3 No Decompression Limits...........................................................................................................51
11.4 Gauge Pressure for Depth of Seawater & Fresh Water .............................................................52
11.5 Equivalent Depths of Seawater & Fresh Water ..........................................................................53
12. DRAWINGS ................................................................................................................................54
12.1 Parts Locator, Model 8211-400 (Front).......................................................................................55
12.2 Parts Locator, Model 8211-400 (Back) .......................................................................................56
12.3 Parts Locator, Model 2825A-8211-28FDW (Diver Communications).........................................57
12.4 Parts Locator, Model 873-400 (Regulator)..................................................................................58

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13. PARTS LISTS ...............................................................................................................................59
13.1 Air Control System, Model 8211 .................................................................................................60
13.2 8211-400 Air Control Panel Assembly........................................................................................61
13.3 8211-400 Air Control Panel Assembly (con’t) .............................................................................62
13.4 Regulator, Pressure Reducing....................................................................................................63
13.5 2825A-8225-400M Front Panel Assembly..................................................................................64
13.6 Recommended Spare Parts........................................................................................................65
14. REPAIR & CALIBRATION LOGS..................................................................................................... 66
14.1 Repair and Maintenance Log for Model 8211.............................................................................66
14.2 Gauge Calibration Log Model PER-201FTM88A01....................................................................67

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1. INTRODUCTION AND SPECIFICATIONS
1.1 Introduction
The Model 8211 is a portable self-contained, shallow water, two diver high and low pressure
air control, communication and pneumo system. The package is a durable co-polymer
composite shell providing a convenient, compact, rugged and professional unit.
Air Control
The air control section consists of two high pressure inputs, a single low pressure input, and a
single diver air output connection.
Standard 3000 PSI MAX Input - Model 8211 comes standard with 2 each CGA850 yokes
attached to 6-foot long HP hoses. The CGA850 yoke limits the maximum input pressure
to 3000 PSI
Optional 4500 PSI MAX Input - Installing the 300 Bar DIN Adapters, Amron Part No. HAS-
300D, will increase the 8211 maximum input pressure limit to 4500 PSI. Simply remove
CGA850 yoke nut and yoke from the bleeder body, screw on the 300 Bar DIN adapters,
and tighten with a wrench. Each input has a shut-off valve and 0-5000 psi gauge.
The high pressure inputs include two scuba bottle yokes with 6 foot hose whips. Each input
has a shut off valve and 0-6000 psi gauge, input pressure range is 500 to 4500 PSI.
Check valves provide protection against back flow of air from a full bottle to an empty, when
switching HP bottles. High pressure air is reduced to desired low pressure via an adjustable
regulator. The input to the regulator is protected against contamination by a 50 micron filter.
Regulator output pressure is adjustable over the range of 0 to 285 psi; a 2 1/2" 0-600 psi
gauge monitors the output pressure. The unit has an over pressurization relief valve, factory
set to 285 psi.
The low pressure input is #6 JIC (3/8), and has a check valve to permit simple switch over
from low pressure air to high pressure air.
Divers air hose connections are O2 fittings, control is via 1/4 turn ball valves permitting
unrestricted flow.
The diver’s pneumo connections are O2 type fittings; pneumo valves are regulating type.
Pneumo gauges are 4.5" high, precision 0.25% of full-scale accuracy, dual scale 0-250
FSW/0-76 MSW with one foot increments.
Depth Monitoring (Pneumo)
The diver’s pneumo connections are O2 fittings, pneumo valves are regulating type. Pneumo
gauges are 4.5" high precision 0.25% of full scale accuracy, dual scale 0-250 FSW/0-76 MSW
with 1 foot increments.

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Communications
The diver communication system is based on the field proven AMRON Model 2825A. The unit
is powered from internal, rechargeable gel-cell batteries; battery charger is provided.
Operating time from fully charged battery is approximately 60 hours. Unit can also be
operated from an external 12 V DC source, via charger jacks on the front panel. The
communicator has a unique battery condition indicator. Steady GREEN light indicates battery
voltage level is good. Blinking GREEN light indicates battery voltage is approaching a low
level (approx. 2-4 hours of operation remain). Steady RED light indicates battery voltage is
below the level necessary to guarantee proper operation. WARNING: When Battery Condition
indicator is steady RED light, communication will stop. The battery condition indicator also
functions in the same manner when operating from an external power source.
Possibly the most useful feature of the AMCOMMAND communicator is the ability to operate
the unit remotely. This feature allows the use of a hand-held, push-to-talk microphone
(included), or a walk and talk type module (optional). This allows the tender (operator) to move
about and still maintain contact with the divers.
The use of the noise canceling push-to-talk microphone automatically disconnects the speaker
when talking to the divers, cutting out the majority of the background noise which greatly
improves the intelligibility of communications.
The communicator provides 20 Watts voice power. This power level provides the volume
necessary to communicate clearly even under difficult conditions. Standard controls include:
power on/off, tender volume, diver volume, speaker on/off, 5-way binding post diver input,
push-to-talk switch, headset/microphone jack, and remote push-to-talk jacks.

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1.2 Air Control Specifications
1.2.1 High Pressure Input
Input Pressure Range.........500-3000 PSI with standard CGA850 Yoke Connections
***500-4500 PSI with optional 300 Bar DIN Adapters
Inlet Valve (Source Select) .........................................................................................2
Gauge - 0-6000 PSI.........................................................................Accuracy +/- 1.5%
Check Valve, prevents reverse inlet flow....................................................................2
Input Filter, In Line Pre Regulator................................................................. 50 Micron
***Available with optional 300 Bar DIN Adapters, Amron Part No. SAA5300
1.2.2 High Pressure Regulator
Outlet Pressure Range .................................................................................0-400 PSI
High Flow.........................................................................................................Cv = 0.8
Max Pressure................................................................................................. 6000 PSI
1.2.3 Low Pressure Input, with Check Valve
Max Pressure................................................................................................... 285 PSI
Diver Outlet Connection, (O2 Fitting)..........................................................................2
Diver Outlet Valve.......................................................................................................2
Air Pressure Gauge, 0-400 PSI .................................Accuracy +/- 1.5% of Full Scale
Over Pressure Relief Valve Set Pressure........................................................ 285 PSI
1.2.4 Panel
Material .................................................................................................Stainless Steel
Powder Coating ................................................Black Textured Semi-Gloss Polyester
Silkscreen Graphics ........................................................................Red, White & Blue

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1.3 Depth Monitoring (Pneumo) Gauge Specifications
Mirrored Scale, 4.5 Inch..............................................................................................2
Range ...................................................................Dual Scale 0-250 FSW/0-76 MSW
Divisions..............................................................................................................1 Foot
Accuracy ........................................................................................0.25% of Full Scale
1.3.1 Pneumo Valve
Regulating Valve, KEL-F Seat....................................................................................2
1.3.2 Outlet Connection
O2 Fitting Chrome Plated Brass.................................................................................2
1.4 Communications Specifications
1.4.1 AMCOM II, Model 2825A-8211 Compact 2-Diver SCU Communicator
Operating Voltage................................................................................12 VDC Nominal
(9 VDC Minimum -18 VDC Maximum)
Power.........................................................................................Rechargeable Battery
Or External Power.........................................................................................12-18 VDC
Operating Time................................................................................Nominal 60 Hours
Charger.............................................................................. 110/220 Volt AC, 50/60 Hz
Frequency Response............................................................................. 300-10000 Hz
Audio Power......................................................................................................20 Watt
Panel Material....................................................................................... Stainless Steel
Powder Coating .................................................Black Texture, Semi-Gloss Polyester
Silkscreen Graphics.............................................................................................White

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1.5 Enclosure Specifications
1.5.1 Case Material
Co-polymer composite material including carrying handle & latches with stainless
steel hardware
1.5.2 Yoke Storage
HP hoses and yokes remain attached to unit and are stored on inside of lid.
1.5.3 Case
Lid closed................................................................. 24-1/2" W x 19-1/2" D x 8-1/2" H
Lid Open ...................................................................... 24-1/2" W x 21-1/2" D x 26" H
Weight: .......................................................................................Approximately 60 lbs.
Color: .............................................................................................International yellow

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2. WARRANTY & SERVICE POLICY
2.1 Limited Warranty
Amron warrants that its manufactured products are free from defects in material and
workmanship under normal use and service, as described in all literature covering the
products for a period of 90 days from date of shipment. Amron’s obligations under this
warranty are limited to the repair of, or replacement of materials at Amron’s discretion. This
warranty shall not cover defects which are the result of misuse, negligence, accident, repair,
or alterations.
2.2 Service Policy
For technical assistance or to request a repair, please call [phone], Monday –Friday, 8
a.m. to 5 p.m. PT. Have the model number and serial number handy and be prepared to offer
as much information as possible about the problem.
Please do not return any product without obtaining a return authorization number. Detailed
instructions will be provided at the time of request.

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3. OPTIONS AND ACCESSORIES
3.1 Model /28A –Wireless Tender Option
The communicator is equipped with a wireless module and includes a Model 2829-11
Wireless Tender Headset. The wireless headset allows the tender freedom to move around.
It requires the divers are wired in 4-Wire mode.
3.2 Amron Heavy-Duty Headset - Model 2401-28
The Model 2401-28 is a heavy-duty headset with boom microphone. It comes equipped with
color-coded, dual banana plugs that mate directly to AMCOM diver communicators. It includes
a 6 ft. straight cord (1.8 meters).
3.3 Amron Standard Headset - Model 2460-28
The Model 2460-28 is a light and comfortable headset designed for extended wear at an
economical price. It comes equipped with color-coded, dual banana plugs that mate directly to
AMCOM diver communicators as well as a six-foot (1.8 meter) straight cord.
3.4 Amron Push-to-Talk Microphone - Model 2405-28
The Model 2405-28 is a hand-held, noise canceling, push-to-talk microphone that provides
excellent sound quality to the diver. It comes equipped with a spiral cord that can be extended
up to 6 feet (1.8 meters)
3.5 Amron Remote Walk-and-Talk Module 2822-28
Designed for Full Duplex (4-Wire) applications, the Model 2822-28 provides the tender with
mobility around the dive site while maintaining communications with the diver. It comes
equipped with a small clip-on belt module that contains the connectors for the headset, and 25
feet (7.6 meters) of lightweight flexible cable. Custom cable lengths are available
3.6 Amron Remote Push-to-Talk Module - Model 2821-28
Designed for 2-Wire applications, the Model 2821-28 provides the tender with mobility around
the dive site while maintaining communications with the diver. It comes equipped with a small
clip-on belt module that contains a Push-to-Talk pushbutton, connector for the headset, and
25 feet (7.6 meters) of lightweight flexible cable. Custom cable lengths are available.
3.7 Amron Wireless Tender Headset –Model 2829-11
A heavy-duty headset combined with a wireless belt module that is compatible with the /28A
option. One headset comes with communicators ordered with the /28A options but additional
headset can be ordered to allow other crew member to monitor communications.
3.8 DIN Adapter 300 Bar - Amron Part Number HAS-300D
Converts a standard Amron CGA850 yoke (3000 PSI) to 300 Bar DIN (4500 PSI) use.

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4. SAFETY AND REGULATIONS
Safe diving does not happen by accident. There are few occupations in the world which require such
a broad range of knowledge and training as diving. There are many diverse factors which can affect
diving safety, i.e. planning, weather, equipment, location, water conditions, as well as the type of work
being done. The single most important factor in eliminating accidents is planning and attention to
detail. Diving knowledge, training and experience are fundamental elements needed to execute a
safe dive.
The following reference materials are recommended as sources of information for running a safe
diving operation:
1. U.S. Department of Labor, OSHA Regulations 1910.401 Sub-part T–Commercial Diving
Operations.
2. U.S. Navy Diving Manual.
3. Divers Handbook of Underwater Calculations.
4.1 Diving Safety and Regulations
4.1.1 Diving Regulations
Several codes and regulations cover diving operations and procedures. In the
United States most commercial diving operations are covered by OSHA
(Occupational Safety and Health Administration) regulations, or individual state
regulations, which are adopted from the federal regulations, and made a part of the
civil code.
While government agencies are exempt from OSHA regulations, they generally fall
under other regulations, which are similar or stricter than OSHA. If they are
completely exempt, they must still abide by the procedures for operating a safe dive.
While no agency (within the U.S., for commercial diving operations) tests or
approves equipment for use, they do establish minimum standards which should be
followed. The suitability of a given piece of equipment for a particular task is left to
the supervisor of the dive. The following information is extracted from the OSHA
regulations for commercial diving operations.
NOTE: The information is not presented as a direct or complete quotation, but rather
as our interpretation of the regulations. Each diving supervisor should obtain a copy
of these regulations for their own use.
WARNING: DO NOT USE THE 8211 FOR THE FOLLOWING:
Mixed gas diving operations with an oxygen level greater than 26%.
Oxygen or oxygen enriched breathing mixtures above 26%.
The Model 8211 is not designed or intended for these applications.

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4.2 Personnel Requirements
1. Each dive team member shall have the experience or training necessary to
perform assigned tasks in a safe and healthful manner. The person operating the Model
8211 must be trained in the proper operating procedures and emergency operating
procedures.
2. It is the responsibility of the designated person in charge of the diving operation
to be on site at all times. He is responsible for all aspects of the diving operation
affecting the health and safety of dive team members.
3. The dive shall be terminated when:
A diver requests termination.
A diver fails to respond to instructions.
Diver communications are lost and cannot be re-established quickly.
A diver begins to use diver carried back-up breathing air or location reserve breathing air.
Operational conditions deteriorate to a point where safe diving cannot be guaranteed.
4.3 Air Supply Requirements
WARNING!
Regardless of the type of air supply being used for surface supplied diving; the diver must
always have a back-up supply of air. Generally this is in the form of a bailout bottle. The back-
up air supply must be adequate to return the diver to the surface; if the dive requires in-water
decompression, this must be accounted for also.
1. The diver's air supply may originate from a low-pressure air compressor, high-
pressure air cylinders, or a combination of both. Regardless of the source, the air must
meet certain established standards of purity and must be supplied in an adequate
volume for breathing.
2. The air supply requirements depend upon the specific factors of each dive such
as depth, duration, level of exertion, and type of diving system (helmet/hat) being used.
It is the dive supervisor's responsibility to ensure that an adequate supply of air is
available and on site for the planned dive. This includes sufficient back up air to safely
return the diver to the surface in the event the primary supply of air is lost.
3. Low-pressure compressors used for breathing air should be specifically designed
for diving. Compressors used to supply air to the divers shall be equipped with a volume
tank which has a check valve on the inlet side, a pressure gauge, relief valve, drain
valve, and a proper filtration system. The output of the air compressor system shall be
tested for air purity every 6 months by means of an air sample.
4. Air compressor intakes shall be located away from and up wind of areas
containing exhaust or other contaminants.

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5. NOTE: OSHA regulations require a decompression chamber capable of
recompressing the diver at the surface to a minimum of 165 FSW (6 ATA) shall be
available at the dive location for a surface supplied air diving to depths deeper than 100
FSW.
4.4 Calibration, Service and Inspection
1. Each depth gauge shall be dead weight tested or calibrated against a master
reference gauge every 6 months or if there is a discrepancy greater than two percent
(2%) between any two equivalent gauges.
2. Each equipment modification, repair, test, calibration, or maintenance service
shall be recorded by means of a tagging or logging system, and include the date and
nature of work performed, and the name of the person performing the work. For your
convenience a repair service log is provided at the end of this manual.
3. Equipment Inspection; Prior to each dive, the equipment shall be inspected and
checked to ensure that it is in proper working order.

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5. CONTROLS & CONNECTIONS
Before using the Model 8211, familiarize yourself with its operating controls and connections. For
simplicity, the controls and connections are divided into three categories. The categories are Air
Control, Pneumo, and Communications.
5.1 Air Control
The Air Control section consists of a high-pressure section and a low-pressure section. The
system is designed to supply breathing air to a diver through an umbilical. This is known as
surface supplied diving. The air the divers are breathing is supplied from the surface.
5.1.1 Standard 3000 PSI MAX Input
All models come standard with 2 each Amron CGA850 yokes attached to 6-foot long
HP hoses. The CGA850 yoke limits the maximum input pressure to 3000 PSI.
5.1.2 Optional 4500 PSI MAX Input
Installing the 300 Bar DIN Adapters: Amron Part No. HAS-300D will increase the
8211 to a maximum input pressure limit to 4500 PSI. Simply remove Amron
CGA850 yoke nut and yoke from bleeder body, screw on 300 Bar DIN adapter and
tighten with a wrench
5.1.3 High-Pressure
The 8211 accepts breathing air from SCUBA bottles or any other suitable source, i.e.
high-pressure flasks. The pressure is reduced to a level suitable to the needs of the
diver via a pressure-reducing regulator. The pressure required by the diver is
determined by the type of helmet/hat being used and the depth the diver is working
at. The general rule of thumb is bottom pressure plus over-bottom pressure required
for a given type of diving helmet / hat. Consult your diving helmet / hat
manufacture/manual for the requirement of the helmet / hat you are using.
The High-Pressure section has two inputs, complete with high-pressure hose whips,
CGA850 SCUBA bottles yokes, and pressure reducing regulator.
1. Source select inlet valve handles are color coded Red and Blue to
correspond to the hose whips which are also color-coded Red and Blue. This
helps the operator identify which valve controls which tank. For maximum
airflow, turn handle counter clockwise four (4) full turns. To shut-off valve, turn
handle clockwise until it stops.
2. Inlet gauge reads actual input pressure of air source. Gauge pressure
range is 0-6000 psi; accuracy is 1-1/2% of full scale.

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3. Check valves (HP section) prevent input air from one source flowing into
a second lower pressure source when both source valves are open. This
simplifies the switch over from one SCUBA bottle to another. NOTE: If both
source valves are left open with full bottles the bottles will be drawn from
equally.
4. The Amron CGA850 input yokes are standard with bleed valves and
color-coded 6-ft. high-pressure hose whips. The CGA850 input yokes are
limited to maximum pressures of 3000 PSI and fit standard SCUBA bottle
valves.
5. A pre-regulator filter prevents debris from contaminating the regulator.
Filter element is 50 micron.
6. High pressure regulator reduce pressure of incoming air from high-
pressure bottles to a level required by diver’s helmet / hat. To increase the
diver’s air pressure, turn knob clockwise to desired setting. To decrease the
diver’s air pressure, turn knob counter clock-wise. NOTE: Regulator is a non-
venting type; in order to reduce the set pressure, air must be flowing through
the regulator.
5.1.4 Low-Pressure
The Low-Pressure section consists of an LP input, low pressure output of regulator,
LP gauge, and diver connections. A small portion of the LP air is also used when
diver depth measurements are made.
The LP input accepts breathing air from a low-pressure source such as a low
pressure diving air compressor. Note: The low-pressure section does not regulate
the air pressure to the diver. The compressor must be set to provide the proper
pressure to the diver.
Breathing air from the low-pressure side of the regulator or the low-pressure input is
routed to the diver’s breathing air connections. A portion of the low-pressure air is
used by the pneumo section for diver depth measurements.
1. Low-pressure input, #6 JIC type fitting. (O2type fitting available).
2. Low-pressure check valve prevents the back flow of air from the HP
regulator output into the LP air source. This also permits simple switch over
from LP to HP air
3. 1/4 Turn ball valve controls flow of air to diver. Ball valve permits
unrestricted flow.
4. Divers air supply gauge reads air pressure to divers, 0-400 PSI.
5. Diver’s air supply outlet connection, O2 (oxygen) type fitting. (37° JIC
optional).

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6. Pressure relief valve, factory set for 285 PSI, vents excess pressure to
atmosphere. Vent is located between diver output connections.
5.2 Depth Monitoring
The Pneumo Fathometer section is used to measure the diver’s depth. Pneumo readings are
made by pressurizing the diver’s pneumo hose. Air is forced through the pneumo hose until all
water is displaced. The air is then shut off and the pressure is read on a high accuracy gauge
calibrated in FSW (feet of seawater). The system components are:
1. Diver pneumo valve (yellow handle) controls the air supply to the pneumo
Fathometer system.
2. Pneumo gauge, dual scale 0-250 FSW/0-76 MSW, mirrored scale, 4.5 inch, high
precision, 0.25% of full scale accuracy.
3. Diver pneumo outlet connections are O2(oxygen) type fittings. (37° JIC fitting
optional).

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5.3 Air Control Front Panel - Communications, Model 8211

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5.4 Communications
The communication system provides two-way communications with the divers. A high power
speaker provides ample volume in noisy environments. Before using the diver communicator,
the operator should be familiar with all the controls and connections. While reading this
manual, you will find capitalized words such as PANEL SPEAKER. These words are to remind
the reader that additional information can be found in this section of the manual.
5.4.1 Tender Controls
POWER SWITCH - The power on/off control.
PUSH-TO-TALK ALL BUTTON - This button allows the tender to talk to all the diver
when operating in the 2-Wire mode. It is not necessary to use this control in the Full
Duplex (4-Wire) mode. When using Full Duplex mode, this control allows the tender
to interrupt the diver by forcing the diver into listen only mode.
EARPHONE VOLUME - This control sets the volume for the tender's earphone
and/or PANEL SPEAKER. Rotate this knob clockwise to increase the volume from
all the divers.
MICROPHONE VOLUME - This control sets the level for the tender's microphone
and/or PANEL MICROPHONE. Rotate this knob clockwise to increase the tender’s
volume to all the divers.
PANEL SPEAKER - A waterproof, acoustic speaker that allows the tender to
monitor communication to the diver and act as a microphone by using the PUSH-
TO-TALK BUTTON. The volume level is controlled by the EARPHONE VOLUME
control and it can be turned off using the SPEAKER SWITCH.
SPEAKER SWITCH - This switch allows the tender to turn off the speaker. If the
tender is using a headset, it may be necessary to turn off the speaker in order to
prevent acoustic feedback.
5.4.2 Tender Connections
TENDER HEADSET - This is the dual banana jack (color-coded black) that
functions as both an output (earphone) and input (microphone) for the tender as
controlled by the PUSH-TO-TALK BUTTON and PUSH-TO-TALK JACK. Using this
connection, the tender can be wired in either 2-Wire or Full Duplex (4-Wire) mode
regardless of the mode used for the diver.
To connect the tender in the Full Duplex (4-Wire) mode, connect the earphone
(black) banana plug of the headset to this jack and the microphone (red) to the
TENDER MICROPHONE jack (red) as shown in the wiring diagram in section 3.6.
In this mode, the tender does not have to use the PUSH-TO-TALK BUTTON to
communicate with a diver who is also connected in the Full Duplex (4-Wire) mode.
This configuration can be used even if the diver is connected in 2-Wire mode. In that
situation, the tender is required to use the PUSH-TO-TALK BUTTON or PUSH-TO-
TALK JACK.