Sherwood Scuba MAGNUM SRB5300 User manual

MAGNUM® SRB5300
OWNER’S MANUAL
Where Depth of Experience Produces the Height of Innovation.
www.SherwoodScuba.com

The owner’s manual uses signal words recommended by the American
National Standards Institute (see ANSI Z535.4) to designate levels of hazard
seriousness. These signal words and their designations are as follows:
DANGER: Indicates an imminently hazardous situation which, if not
avoided, will result in death or serious injury. This signal word is to
be limited to the most extreme situations.
WARNING: Indicates a potenially hazardous situation which, if not
avoided, could result in death or serious injury.
CAUTION: Indicates a potenially hazardous situation which, if not
avoided, may result in minor or moderate injury. It may also be used
to alert against unsafe practices.

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TABLE OF CONTENTS
1.0 Introduction - Simply Reliable ..................................4
2.0 Safety Information ................................................5
2.1 Important Warnings ...............................................................5
2.2 Important Cautions ................................................................6
3.0 Routine Maintenance & Handling Tips ........................6
3.1 Pre-Dive Checks .....................................................................7
3.2 Post-Dive Care .......................................................................8
4.0 Sherwood Scuba Limited Warranty Information .............9
4.1 Two Year Limited Warranty ....................................................9
4.2 Disclaimer & Limitation of Remedy .....................................11
4.3 Things You Should Know About Your
Two Year Limited Warranty ..................................................12
5.0 Features .......................................................... 12
5.1 First Stage ............................................................................12
5.2 Second Stage .......................................................................13
6.0 Specifications ................................................... 14

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1.0 INTRODUCTION - SIMPLY RELIABLE.
Congratulations! You are now the owner of a new Sherwood Scuba
regulator. You’re about to experience the Sherwood difference
in diving equipment...regulators that are simply reliable. At
Sherwood, we focus on the type of diving you do, then design
products that address your specific needs. The simple, purposeful
designs of all Sherwood regulators provide you with reliable,
trouble-free performance dive after dive.
Since 1923, Sherwood has been providing people in the medical,
industrial and recreational fields with the finest in precision
regulators and valves. We’re experts at creating innovative gas
control products that keep pace with today’s changing needs.
Our state-of-the-art technology ensures that each product we
manufacture performs precisely as designed. All Sherwood
regulators conform both to ISO 9001 and EN250 standards
Sherwood Scuba and our worldwide network of authorized
dealers are always ready to serve you. For more information on
our products, and for the dealer nearest you, write to Sherwood
Scuba, LLC, 4 Chrysler, Irvine, CA 92618. Thank you for choosing
Sherwood!
PLEASE NOTE: This Owner’s Manual contains important safety
and maintenance information. Please make sure you read and
understand this entire manual before using your Sherwood Scuba
regulator. If you have any questions about the use and care of your
regulator, contact your authorized Sherwood Scuba dealer.

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2.0 SAFETY INFORMATION
Please read carefully!
2.1 IMPORTANT WARNINGS
WARNING
1. Sherwood Self-Contained Underwater Breathing Apparatus
(SCUBA) equipment is to be used only by individuals trained
and certified by a nationally recognized scuba training
agency. Diving without the necessary training in safe diving
procedues, or without observing the practices outlined
by your training agency for your level of certification, is
extremely hazardous and could result in serious personal
injury or death. This owner’s manual is in no way a
substitute for the instruction received from a certified scuba
training agency.
2. Sherwood regulators must be serviced only by dealers or
persons trained and authorized to service Sherwood Scuba
equipment. At no time should any unauthorized person
attempt to repair the regulator or adjust any nuts, bolts or
screws other than those used to mount the regulator to, or
dismount it from the tank valve. Scuba equipment that is not
properly serviced could malfunction during use, putting the
diver at risk of serious personal injury or death.
3. Note to European Customers: This regulator has passed
EN250 Section 5.13.3 for regulators used below 10 degrees
C (operating at 4 degrees C). Breathing air used in Sherwood
Scuba regulators should meet European EN132 standards.

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2.2 IMPORTANT CAUTIONS
CAUTION
1. To prevent personal injury and damage, install the low
pressure hose only into the low pressure outlet of the first
stage regulator.
2. Do not attach the low pressure hose to the high pressure
outlet for the submersible tank pressure gauge.
3. The high pressure outlet is normally marked “HP” (on
current Sherwood Scuba regulators, the high pressure
outlets are distinctly larger than the low pressure outlets
and are clearly marked “HP”). If the regulator outlet is not
marked, install a submersible pressure gauge in the outlet
and test the pressure with a full tank of air. The low pressure
outlet should not show more than 200 psig (14 Bar).
4. The O-ring hose fittings will seal with hand-tight pressure.
However, they should be snugged up gently with a small
wrench to a maximum of 40 in. lbs. (4.5 joules). Excessive
tightening will not help the seal and may damage the
parts (see DEMA Guidelines No. 101, Low Pressure Hose
Installation Caution Statement: ANSI American National
Standard for Underwater Safety, paragraph 9.3.1).
3.0 ROUTINE MAINTENANCE & HANDLING TIPS
How you take care of your Sherwood regulator before, after and
between dives will greatly affect the regulator’s functioning and
durability. Following are a few tips that will help you get the best
performance and wear from your new regulator.

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3.1 PRE-DIVE CHECKS
WARNING
It is safe diving practice to inspect your regulator before
each use. Check for signs of damage, loose parts, or
possible malfunction. If you detect a problem, have the
regulator properly serviced by an authorized Sherwood
Scuba dealer before you use it agian. Using a regulator that
shows signs of damage or substandard performance puts
the diver at risk of serious personal injury or death.
1. Before mounting any Scuba regulator onto a valve, you must
open the valve briefly to blow out any water trapped in the
outlet area of the valve. Failing to perform this simple step will
often result in water and contaminants being blown into the
delicate interior of the regulator, which in turn will cause future
mechanical problems in the regulator.
2. Before mounting your Sherwood regulator on your tank valve,
check the hoses and hose connections for looseness, cuts,
abrasions or other signs of damage. Slide the hose protectors
back to inspect the areas of the hose normally covered.
3. Just before turning on the air tank valve, check to make sure that
the yoke nut or DIN connection is tight and that the regulator
body is aligned properly, with no kinks in the hoses.
4. Turn the tank valve on slowly and listen for leaks.

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CAUTION
Lifting the tank by the regulator or hoses may loosen a
previously tight connection, which could cause unexpected
air loss and put the diver at risk during a subsequent dive.
5. Surface test the regulator by breathing lightly through the
mouthpiece. Purging the regulator above the water’s surface
is NOT an appropriate method for testing the function of the
regulator.
3.2 POST-DIVE CARE
1. After the dive, blow all water out of the dust cap with clean dry air
and place the cap securely on the regulator inlet. On multiple tank
dives, keep salt water out of the regulator inlet when changing
the tanks. Neglect of these simple procedures is a major cause of
corrosion and wear in scuba regulators. Sherwoood’s exclusive
Dry Air Bleed System keeps all other water-borne contamination
out of the first stage body.
NOTE
A tiny stream of bubbles escaping from a small black valve
on the first stage indicates that the Dry Air Bleed System
is working. The amount of air used is negligible (13-25
cc/min.). Check the system periodically, particularly after
servicing, to ensure that there is some air escaping from
the black one-way bleed valve. If no air is escaping from
the valve when air pressure is applied to the first stage,
you should have the regulator inspected by your authorized
Sherwood Scuba dealer.

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2. With the dust cap securely in place, rince the first and second
stage in clean fresh water. DO NOT purge the regulator before
or during rinsing since this may introduce water into the second
stage and the low pressure hose. Shake or blow all excess water
from the second stage and allow the entire regulator to air dry
before storing.
3. Store the regulator in a clean bag or storage box, away from
sunlight, excessive heat and humidity.
4.0 SHERWOOD SCUBA
LIMITED WARRANTY INFORMATION
4.1 TWO YEAR LIMITED WARRANTY
1. Sherwood warrants that Sherwood Scuba regulators purchased
from authorized Sherwood Scuba dealers shall be free from
defects in materials and workmanship for twenty-four (24)
months from that date of original purchase. Under this limited
warranty, Sherwood will either repair or replace, at its sole
NOTE
A tiny stream of bubbles escaping from a small black valve
on the first stage indicates that the Dry Air Bleed System
is working. The amount of air used is negligible (13-25
cc/min.). Check the system periodically, particularly after
servicing, to ensure that there is some air escaping from
the black one-way bleed valve. If no air is escaping from
the valve when air pressure is applied to the first stage,
you should have the regulator inspected by your authorized
Sherwood Scuba dealer.

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option, any original equipment or parts that fail to perform as
intended. When this limited warranty is in force, it covers the cost
of necessary replacement parts, including hoses, mouthpieces,
exhaust valves, and diaphragms. Labor charges are not included
and must be paid by you.
2. You must save the original purchase receipt. It is proof of when
the regulator was purchsed. The date also lets you know when
your annual service should be performed.
3. This limited warranty applies only to the original purchaser, and
then only to certified divers. Sherwood makes no warranty or
representation regarding the performance of any products used
in conjunction with Sherwood’s products.
4. This limited warranty applies only to regulators sold through
authorized Sherwood Scuba dealers. Authorized Sherwood
Scuba dealers do not sell Sherwood Scuba regulators through
mail order.
5. This limited warranty shall be void if the regulator has been
misused, abused, altered, changed, or modified.
6. This warranty gives you specific legal rights, and you may also
have other rights which may vary from state to state.
7. If you have any questions concerning the Two (2) Year Limited
Warranty, please address them to:
Sherwood Scuba, LLC
4 Chrysler
Irvine, CA 92618

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4.2 DISCLAIMER AND LIMITATION OF REMEDY
(Some states do not allow limitations on how long an implied
warranty lasts or do not allow exclusion of incidental or
consequential damages, so the following limitations or exclusions
may not apply to you.)
Sherwood expressly limits any and all warranties, expressed or
implied, to the two year term of the limited warranty as set forth
above. All remedies are waived unless claim is made within the
applicable twenty-four (24) month period.
Your remedies are limited to those contained herein and are in
lieu of all other remedies, whether based on breach of warranty
or contract, negligence, strict product liability or other tort.
Sherwood specifically disclaims liability for any consequential,
special or indirect damages arising out of the use of your
regulator.
CAUTION
Scuba products are subject to conditions of extreme wear
and corrosion. Inspection and maintenance are required
to ensure continued performance. Sherwood recommends
that you have your regulator inspected once a year on the
anniversary date of its purchase at any authorized Sherwood
Scuba dealer worldwide. Sherwood Scuba equipment
should be used by certified scuba divers only.

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4.3 THINGS YOU SHOULD KNOW ABOUT
YOUR TWO YEAR LIMITED WARRANTY
1. To keep the owner two year warranty in effect, you must have
your regulator inspected and serviced annually, within 30 days
before or after the anniversary of the purchase date. Failure
to do so will invalidate your warranty. This servicing must be
performed by an authorized Sherwood Scuba dealer.
2. Keep your original proof of purchase receipt. This is required to
show that you are the original owner of the regulator. You must
bring it with you when you bring your regulator in for servicing.
3. The two plastic rings attached to the regulator hose protector
represent the two annual servicings covered by your warranty.
After the second annual servicing, the warranty rings will be
gone and the warranty will no longer be in effect. SHERWOOD
EMPHATICALLY RECOMMENDS THAT YOU CONTINUE TO
BRING IN YOUR REGULATOR FOR SERVICING ON AN ANNUAL
BASIS.
5.0 MAGNUM SRB5300
FEATURES
5.1 FIRST STAGE
1. Like all current Sherwood Scuba regulators, the Magnum is
equipped with Sherwood’s patented Dry Air Bleed System. This
unique feature accomplishes the very important task of keeping
the interior of the first stage, including the main spring chamber,

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clean and dry. The Dry Air Bleed System helps give the first stage
durability, stable output pressure. and outstanding resistance to
cold water freezing effects.
2. Optimized internal porting maximizes flow rate capability
to supply an appropriate air supply for high work efforts
encountered during some dives.
5.2 SECOND STAGE
1. The compact design of the Magnum minimizes the size and
hydrodynamic drag of the second stage.
2. As with the first stage, the second stage’s simplicity, ruggedness
and ease of maintenance make it a popular regulator wherever
constant hard use is a factor.

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6.0 SPECIFICATIONS
REGULATOR MODEL .................................. Magnum SRB5300
AIR FLOW ................................................... 33 cu. ft./min. (935 liters/min)
@ 1 atmosphere
INHALATION RESISTANCE .......................... 1.0” WC (2.5 cm WC)
@ 1 atmosphere
EXHALATION RESISTANCE ......................... .7” WC max. (1.8 cm WC)
@ 1 atmosphere
FIRST STAGE REGULATOR
TYPE ........................................................... Downstream Flow-by piston with moving
orifice balancing and Dry Air Bleed
(Positive Air Purge)
U.S. Patent 4,226,257
(other patents pending)
WEIGHT ...................................................... 1 lb. 11 oz. (.77 kg)
INTERSTAGE PRESSURE ............................ 135-150 psi (9-10 Bar)
MAXIMUM INLET PRESSURE ..................... 232 Bar for SRB5300CE Model
POSITIVE AIR PURGE FLOW RATE ............. 13-25 cc/minute
# LOW PRESSURE PORTS ......................... 4 (3/8”-24 UNF)
# HIGH PRESSURE PORTS ......................... 2 (7/16”-20 UNF)
MATERIALS ................................................ Body ------------------ CDA-360 Brass
Yoke ------------------ CDA-377 Brass
O-rings --------------- Buna-N
Bleed Valve ---------- Ethylene Propylene
Piston Seat ----------- Teflon®
Lubricant ------------- Christo-Lube®
SECOND STAGE REGULATOR
TYPE ........................................................... Downstream, diaphragm,
variable fulcrum
U.S. Patent 3,991,785
WEIGHT ...................................................... 5.1 oz. (.15 kg) (without hose)
HOSE LENGTH ............................................ 31 in. (.79 m.)
MATERIALS ................................................ Cover ----------------- Thermoplastic vinyl
Case ------------------ Triax®
Poppet Seat ---------- Low temperature
NBR polymer
O-rings -------------- Buna-N
Diaphragm ----------- Tufel® (clear blue)
Exhaust Valve ------- Thermoplastic
Elastomer (blue)
Mouth Piece --------- Liquid silicone rubber
Maximum certified depth is 50m.

Printed on recycled paper
Printed in USA
EC Type examination (Article 10) by:
SGS Yarsley International Certification Services Limited
GAW House
Alperton Lane
Wembley
Middlesex HAO 1 WU
Notified Body No. 0120
Meets EN250 Standards
Sherwood Scuba, the S-Ball and Magnum
are trademarks of Sherwood Scuba,LLC. All other names are trademarks of their
respective owners. © Copyright 2003 Sherwood Scuba®, LLC.
All products are subject to change without notice
Sherwood Scuba valves and regulators are registered
under the following patent numbers:
4,356,820; 4,152,848; 4,226,257; D311,788; D314,904.
M-SC10B99
Part Number M-5300
Where Depth of Experience Produces the Height of Innovation.
4 Chrysler, Irvine, CA 92618
www.SherwoodScuba.com