Scuba Force SF2 ECCR User manual

SF2 ECCR
OPERATION MANUAL

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SF2 ECCR OPERATION MANUAL
Table of Contents
Copyright / Warning 4
Safety 5
Preface 7
Chapter 1 –How the SF2 works 8
Chapter 2 –Soda Lime 11
2.1 Scrubber Duration Time 12
2.2 Storage 13
2.3 Influence of temperature on the Soda Lime output 13
2.4 Influence of exertion on scrubber duration time 13
2.5 SF2 scrubber duration time 13
Chapter 3 –Oxygen sensors 14
3.1 Functional principle and design of a sensor 15
3.2 Influence of pressure 16
3.3 Influence of moisture and water 16
3.4 Aging oxygen sensors 17
Chapter 4 –SF2 Components 18
4.1 Head 19
4.2 Midpart 19
4.3 Frame and accessoires 20
Chapter 5 –SF2 Assembly 21
5.1 Cylinder assembly 21
5.2 Bellow assembly 21
5.3 Scrubber and carbon fiber tube assembly 23
5.4 Battrey solenoid assembly 24
5.5 Sensor assembly 24
5.6 Loop assembly 26
Chapter 6 –Assembly accessories 29
6.1 Manual Add Kit & Off Board Gas 29
6.2 Assembly regulators, wing & harness 30
Chapter 7 - Calibration oxygen sensors 33
Chapter 8 –Predive Saftey Check 35
8.1 Check gas flow / gas direction 35
8.2 Positive- and negative test 36
8.3 Assembly Check 37
8.4 Predive Check 37
8.5 Prejump Check 38
Chapter 9 –After the dive 39
9.1 Disassembly of the SF2 39
9.2 Cleaning of the SF2 40
9.3 Disinfict 40
9.4 Transport and storage 41
Chapter 10 –Maintenance 41
Chapter 11 –Attachement 42
12.1 Checklist 42
12.2 Aditional Operation Manuals 43

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Congratulations on purchasing your SF2 ECCR rebreather. This unit has been
carefully manufactured to exact standards using high quality materials. When used
as directed, the SF2 ECCR will make diving more comfortable, enjoyable and
exciting.
The SF2 ECCR is intended for use by certified divers who are trained in the use of
rebreather systems or those divers who are under the direct supervision of a
qualified instructor.
Even if you are experienced in using rebreather systems, we strongly recommend
that you take the time to read these instructions. It contains many important safety
instructions and techniques that will help to extend the life of your rebreather.
On-line manual can be located on our website www.scubaforce.eu
For further questions, we can be contacted at:
SCUBA FORCE
Dive2gether.net Tauchsport GmbH
Reststrauch 197
41199 Mönchengladbach
Tel.: [phone]
Email: [email protected]
Der SF2 ECCR certified after EN 14143:20132-10 regulation (EU) 2016/425
Implementing test institute:
DEKRA
Testing and Certification GmbH
Adlerstrasse 29
45307 Essen
We would like to thank Dr. Frank Hartig, Dr. Andrea Köhler and Uwe Breidenstein for
providing texts, photos and graphics. And to all the photographers worldwide who
keep providing us with fantastic images, thank you.

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Copyright
All rights, intellectual property, and technical design reserved. No part of this
publication may be reproduced, distributed, or transmitted in any form or by any
means, including photocopying, recording, or other electronic or mechanical
methods, without the prior written permission of the publisher, SCUBA FORCE –
dive2gether.net Tauchsport GmbH.
Please read operating instructions carefully before using your rebreather.
Operating instructions are not a substitute for a general training manual for
rebreather units. You must be properly trained by an authorized SF2
instructor.
Warning, caution and notes
Pay particular attention to all information marked with warning, caution and note
according to the following symbols:
WARNING
A WARNING indicates a practice or situation which, if not avoided
could result in hazardous or unsafe practices that may result in severe
personal injury or death
CAUTION
CAUTION indicates a situation or usage
instruction that could damage
the product and result in injury to the user.
NOTE
NOTE emphasizes important points, notes,
and reminders.
WARNING
These operating procedures contain important
instructions for the correct use and care of your
new rebreather. It is therefore extremely
important that you take the time to read this
manual so that you can fully understand and
enjoy all of the features of your rebreather.
Improper use of your rebreather can result in
serious injury or death.
TECHNICAL HELP
If there is any ambiguity in this manual, or if you do not get sufficient answers from
your dive shop or diving instructor, please contact us

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Safety
Important Safety Instruction
This rebreather is intended for use by certified scuba divers who have completed a
rebreather course, or those who are being trained and supervised by a qualified
instructor.
WARNING
Follow all instructions and adhere to these safety measures.
Incorrect or improper handling of the rebreather can result
in serious injury or death.
WARNING
This manual is NOT a substitute for a rebreather training course
administrated by a qualified instructor. DO NOT USE a
rebreather until you have practiced and perfected practical skills,
including emergency skills, in a supervised environment and
under the supervision of an instructor who is certified by a
nationally recognized diving training organization and authorized
to train in SF2 rebreather use.
WARNING
Careless use of the SF2 can cause unconsciousness due to lack
of oxygen in any environment without prior warning signs.
Careless use of the SF2 at depths underwater greater than 6
MSW (meters of sea water) [20 FSW (feet of sea water)] can
cause unconsciousness without warning. Either of these
situations can cause serious injury or death. The SF2 is equipped
with a sophisticated electronic control system that enables a
properly trained user to avoid these situations. It is the sole
responsibility of the user to carefully monitor the displays on this
system while using the SF2 and to have a knowledge of response
measures in the event of a problem.

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Welcome to a new, quiet world of diving. With the acquisition of the SF2
ECCR you have taken another big step in your diving development.
New adventures are waiting for you. With a rebreather you can reach regions
that were previously unavailable to you.
The SF2 ECCR is one of the most popular and best-selling rebreather devices
worldwide. Straightforward design, high reliability, and simple pre dive
preparation and post dive follow-up are just a few of the points that have led
to the SF2 ECCR having a large fan base among sport, wreck and cave
divers. Whenever high reliability and special performance is required, the SF2
is used.
Soon you too will be one of the enthusiastic fans of rebreather diving in
general and the SF2 in particular.
But first you have to study and work. Your SF2 diving course will start
shortly and within a short period of time you will be confronted with many
new theoretical and practical knowledge and skills.
Rebreather diving is fun, but knowledge and skills are important to make it
safe. We believe the well-trained diver is one who is willing to commit to
continuous learning and safe training programs to perfect his/her skills.
Diving equipment, including a rebreather, are tools the diver must learn to
master - not the other way around.

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Chapter 1 - How the SF2 works
The SF2 belongs to the CCR rebreather category: Closed Circuit Rebreather This
describes a completely closed loop system in which only the metabolized oxygen
used (consumed) is added, this can be done manually (described as MCCR) or
electronically as with the SF2 ECCR.
The SF2 is an ECCR Electronic Closed Circuit Rebreather. The basic principle is
actually relatively simple and has been tried and tested for decades. The O2 content
in the breathing gas is measured via oxygen sensors - more on this later. If this
proportion falls below a pre-set value, oxygen flows into the system via an
electronically controlled solenoid valve (solenoid) until it again corresponds to the set
value.
What sounds simple in theory is influenced by various factors in practice, for
example increasing or decreasing pressure when descending or ascending.
In contrast to the open circuit system, the diver does not release any gas into the
environment when diving, so he breathes in a closed loop circuit which explains the
name. (If there is overpressure in the system, for example when surfacing, gas is
released into the environment even with a closed rebreather.)
Maintaining this circuit is important and must be checked before every dive. With the
SF2, the flutter valves, also called directional membranes, are located in the
mouthpiece. From the diver's point of view, i.e. with the device on his back, gas flows
from right to left.

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Our body consumes (metabolizes) the oxygen we breathe. This creates carbon
dioxide - CO2. We normally release this gas back into the environment when we
breathe. But since our breathing circuit is closed, the CO2 also remains in the
system. Hypercapnia, i.e. an increase in the level of carbon dioxide in the blood
(approx. 45 mmHg) can quickly lead to life-threatening situations, especially under
water. To prevent this from happening, the resulting CO2 is bound in a canister with
soda lime, which we will also go into briefly later.

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Since we can only
breathe in a circuit if
the gas has a flexible
volume in which to
collect it, in our body
that flexible volume is
the lungs. The SF2
has a "counterlung" in
the form of a bellows.
This type of
counterlung
configuration is unique
in the rebreather world
and has various
advantages: It is
compact, easy to
assemble, protected
by the lower carbon
tube. Last but not
least, an important
feature of the
counterlung is a huge
water trap at the
lowest point of where
the pressure relief
valve is located.
This describes the most important components of the SF2 and a rebreather in
general. The only thing missing is the gas addition supply. As mentioned at the
beginning, the consumed oxygen is added back to the system in pure form. The SF2
has an oxygen cylinder which, again from the perspective of the diver, wearing the
device located on the divers’ right side. Pure oxygen becomes "toxic" from a depth of
about twenty feet (six meters) and can no longer be breathed safely. So the oxygen
has to be diluted. In English this is called dilute and that is why the term diluent bottle
has established itself. Two gases are used as diluent in the SF2: On the one hand,
normal air and, on the other, trimix mixtures, i.e. a gas consisting of oxygen, nitrogen
and helium.
The diagram on the next page gives a good overview of the structure of the SF2

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SCHEMATIC REPRESENTATION SF2 ECCR