mcmurdo E5; G5 User manual

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mcmurdomcmurdo
mcmurdo
E5/G5
E5/G5E5/G5
E5/G5 EPIRB
EPIRB EPIRB
EPIRB
Service Manual
Service ManualService Manual
Service Manual

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Smartfind EPIRB service manual Page 1
Table of Contents
1. Introduction ..........................................................................................................3
1.1. Scope..............................................................................................................3
1.2. Applicability .....................................................................................................3
1.3. Servicing equipment .......................................................................................4
1.4. Safety notices .................................................................................................5
1.5. alse alarms ...................................................................................................7
2. Assessment ..........................................................................................................9
2.1. Maintenance tasks..........................................................................................9
2.2. Routine testing ................................................................................................9
2.3. Assessment ..................................................................................................10
3. Maintenance procedures...................................................................................12
3.1. Inspection......................................................................................................12
3.2. unctional test...............................................................................................14
3.3. Message read ...............................................................................................17
3.4. Internal inspection.........................................................................................18
3.5. Disassembly..................................................................................................19
3.6. Re-assembly .................................................................................................22
3.7. Leak testing...................................................................................................25
3.8. Battery change..............................................................................................26
3.9. Reset the Run Time counters on the PCB ...................................................28
3.10. HRU replacement......................................................................................29
3.11. Programming.............................................................................................30
. Fault finding........................................................................................................32
5. Repair procedures .............................................................................................35
6. Spares .................................................................................................................36
Appendix 1 : Specification .......................................................................................37
Appendix 2 : IMO recommendations.......................................................................37
Disclaimer
McMurdo is a brand name operated by Signature Industries Limited.
The information and illustrations contained in this publication are to the best of our knowledge correct
at the time of going to print. We reserve the right to change specifications, equipment, installation and
maintenance instructions without notice as part of our policy of continuous product development and
improvement. No part of this publication may be reproduced, stored in a retrieval system or
transmitted in any form, electronic or otherwise without permission in writing from McMurdo, Signature
Industries Limited. No liability can be accepted for any inaccuracies or omissions in the publication,
although every care has been taken to make it as complete and accurate as possible.

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1. INTRODUCTION
The Emergency Position Indicating Radio Beacon (EPIRB) is a device used to alert
search and rescue services in the event of an emergency. It activates via a sea water
switch whilst floating in the sea. The EPIRB contains the following functions:
406MHz transmitter A powerful 5 Watt transmission is encoded with either
a unique serial number or the vessel’s call sign / MMSI.
The signal is relayed via satellite to the rescue centre.
121.5MHz transmitter A low power transmission is amplitude modulated with
a swept audio tone and acts as a homing beacon. When the
rescue services get close this allows them to direction find on
the signal.
lashing light (strobe) A bright light flashes every 2.6 seconds as a visual aid
during the last stage of rescue.
Buzzer Audible alarm/indicator
GPS receiver (optional) The module receives and decodes the Global Positioning
System signals from a satellite network and computes the
position of the EPIRB.
The vessels flag state and the vessel identity or unit serial number is programmed into the
EPIRB as part of the 406MHz transmission, thus making the EPIRB unique. Transferring an
EPIRB to another vessel either involves re-programming, or re-registration.
The product is non-hazardous for transportation.
It is available with either a carry-safe manual bracket or auto release cover.
1.1. Scope
This manual provides the instructions to enable routine and emergency servicing of the
EPIRB equipment listed below. This manual represents the original equipment
manufacturer’s (OEM) service documentation applicable to these products.
Shore based maintenance procedures (in accordance with IMO Circ 1039) is covered in
82-1039 and annual inspection (in accordance with IMO Circ 1040) is covered in 82-
1040.
1.2. Applicability
This manual applies to the following 406MHz EPIRB equipment:
• McMurdo Smartfind Plus or G5 GPS
• McMurdo Smartfind or E5 Non-GPS
• Sailor SGE406-II GPS
• Sailor SE406-II Non-GPS
• Simrad EG50 GPS
• Simrad EP50 Non-GPS
Units without integral GPS have serial numbers beginning with 100.
Units with integral GPS have serial numbers beginning with 200.

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1.3. Servicing equipment
The following tools and equipment is required to carry out the servicing detailed in this
procedure.
Equipment:
Message reader
Screened box
Leak testing equipment (SBM testing only)
GPS repeater (SBM testing only)
Static-safe work area with operator wrist strap
Multimeter with voltage and resistance scales
Programming kit :
82-950A Light pen
82-951A EPROG5 (McMurdo variant)
Bar magnet or manual bracket with incorporated magnet
Shorting link for sea switches
Battery discharge load (made on-site as required)
Handtools:
Calibrated torque driver (0.6 Nm) with attachments:
7mm A/ socket (M4)
Small cross-headed screwdriver
Large cross-headed screwdriver
Antistatic precautions
The electronics section of the EPIRB is sensitive to electrostatic discharge (ESD) which
can cause immediate or hidden long term damage. It is important that the PCB is only
handled under suitable antistatic conditions.
Ideally, a fully grounded workstation, which has conductive surfaces to avoid the build up
of static charge, should be used.
As a minimum, the operator must be connected to a good earth point through a
resistance of 1Mohm. This is usually achieved by wearing a suitable wrist strap.

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1. . Safety notices
Please read the following information for your safety:
This product has been assessed as presenting negligible hazard in a sealed serviceable
state.
Safety analysis
The following table summarises the nature of the hazard which may be present when the
unit is opened or serviced; each hazard is discussed at greater length in the detailed
sections.
Hazard cause Hazard identification Precautions
Lithium battery Explosive risk, corrosive fumes,
fire, biological hazard
Handle appropriately, avoid
contact
Strobe Bright light Avoid staring at light
Radio frequency
radiation
Physiological hazard Avoid close or prolonged
exposure. Do not touch the
antenna during 406MHz
transmissions
IPA Irritation, highly flammable Avoid contact, ventilate well
Lithium batteries
Hazardous chemicals Wear gloves
The batteries used in these products contain Lithium (Li). Lithium is flammable, reacts
violently with water and constitutes a biological hazard. These batteries are hazardous if
short-circuited, punctured, incinerated or deformed.
Lithium batteries must not be short circuited.
Lithium batteries must be handled, transported and disposed of using appropriate safety
precautions. The use of rubber gloves as a routine precaution is recommended.
In the event of leakage of the battery electrolyte (which can be recognised by a pungent
odour), take care to avoid contact, particularly with open wounds; do not ingest the
material. Do not attempt to discharge a leaking battery – remove it using appropriate
handling materials and seal in a plastic bag, then dispose of it through an approved
environmental disposal agent, or in accordance with local regulations.

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Strobe radiation
The strobe lights fitted to EPIRBs produce intense flashes of light. No damage is likely to
be caused by intermittent exposure, but prolonged exposure should be avoided.
Radio frequency radiation
An EPIRB produces radio frequency radiation when it is activated. The
radiated level is below 13W with a duty cycle of 1%. Due to the low
duty cycle this is not considered to be a hazard; however, it is
advisable to avoid touching the antenna of a transmitting EPIRB.
General precautions for chemical agents (adhesives, greases, IPA)
Observe all safety precautions relevant to the country of operation. As a general rule,
protective overalls, gloves and goggles should be worn when handling these chemical
agents, but different countries may have additional requirements which must be
observed.
Ensure that all chemical agents are handled in accordance with the manufacturer's
instructions, and that suitable protective clothing is worn.
Make sure that the working area is well ventilated, and that chemical substances are not
left exposed. Observe good hygiene practices; do not eat, drink or smoke when handling
chemicals.
Read the manufacturer's instructions before using any chemical agent.
Wear goggles Wear overalls Wash hands Wear gloves
Radio frequency
radiation

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1.5. False alarms
Every care must be taken to avoid the generation of false alarms.
Modern EPIRBs are activated by sea switches. The mounting bracket (both Autocover
and Manual) incorporates a magnet to disable the sea switch. However, if the EPIRB is
wrongly fitted the magnet will fail to disable the sea switch, so water may activate the
EPIRB. To prevent this, simply ensure that the EPIRB is correctly fitted.
or test purposes the EPIRB may be operated in the following ways without generating
a false alarm:
1. Self test mode (but avoid repetitive self tests)
2. Live mode for less than 50 seconds (after 50s a live transmission is made)
3. Live mode in a screened enclosure
If for any reason the EPIRB is activated outside a screened enclosure (other than as a
self test) for more than 50 seconds, it must be assumed that a false alarm has been
generated. If this occurs:
1. Deactivate the EPIRB (see below).
2. The rescue services must be informed that there has been a false alarm. Use any
means available to contact the coastguard or the nearest Maritime Rescue
Coordination Centre (MRCC); state that there has probably been a false alarm,
identify the location of the EPIRB and if possible give the EPIRB ID.
De-activating a live EPIRB
Remove the EPIRB from any water and dry the outside. Wait about 8 seconds for the unit
to de-activate automatically.
If it fails to deactivate ensure that the activation switch is fully off (slide to right).
If the EPIRB continues to transmit, it may have a fault. To prevent further nuisance, it is
recommended that the unit is allowed to exhaust its battery whilst the alarm signals are
suppressed. The recommended procedure is:
1. Cut off the antenna.
2. Place EPIRB in a metal enclosure, or wrap in metal foil.
3. Leave for three days until the battery is exhausted.
If it is absolutely necessary to fully disable the EPIRB (by unplugging the battery) then
please see the relevant section of this manual.
NOTE: All EPIRBs (even ‘unprogrammed’ ones) will transmit.

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2. ASSESSMENT
2.1. Maintenance tasks
Service providers are reminded that it is their responsibility to ensure that the procedures
herein are followed, that only McMurdo approved parts are fitted and that good common
practice is observed.
alse alarms caused by inadvertent activation must be avoided. We recommend that
EPIRB testing is only done in self-test mode, where possible, to avoid false alarms.
The functions which can be performed by service providers are:
• Routine testing
• Reprogramming
• Message reading and verification
• Power verification
• Battery replacement
• Battery life/GPS test reset
• Leak testing
• HRU replacement
• ault diagnosis and repair
• GPS Test
2.2. Routine testing
An EPIRB should be tested monthly by its owner to ensure functionality. Regular testing
is essential. The EPIRB should be inspected for mechanical damage at the same time.
An EPIRB fitted to a GMDSS compliant vessel is recommended to undergo an inspection
at yearly intervals and shore based maintenance every 5 years (maximum). To carry out
shore based maintenance requires certification by the manufacturer of the EPIRB.
Whatever the reason for the return the EPIRB must be subjected to a full assessment
before any other action is taken. The agent has a responsibility to ensure the EPIRB is
completely serviceable and is fit for its purpose.
Included in the user handbook are full details on:
Installation
Emergency procedure
LED operation
Therefore these items are not repeated in this manual.

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2.3. Assessment
Every EPIRB returned for servicing, of whatever nature, must be fully assessed to
determine its operational status. The diagram shows the tasks which must be carried out
for each servicing situation.
If the EPIRB is opened for any reason, it is recommended a new sealing kit is fitted
.
Assessment form
The assessment form, shown on the next page, is an essential tool in performing
diagnosis. It may be used to support customer billing, and must accompany any warranty
return to the manufacturer.
The first section of the form records the customer, the EPIRB and the reason for return
(as 'Customer comments'). It is essential to record the identity details from the EPIRB
rear label, as these will be necessary for comparison with the transmitted data. The
expiry date must be noted; if less than 6 months life remains, a battery change should be
recommended to the customer.
Opening the EPIRB for internal inspection is only required if a problem is found.
RECEIPT
Assessment
Inspect
unctional test
Message read
unctional test
Message read
Program
Print forms & labels
Mark HRU date
it HRU
Mark dates
RETURN
HRU change Reprogram
Disassemble
Internal inspection
ault find
Repair
Disassemble
Internal inspection
it battery
Mark Dates
Reassemble
Leak test
Fault found
Battery
change
Reset EPIRB
Reassemble

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EPIRB ASSESSMENT Ref No Date
Customer Vessel
Type Man. Serial No - Battery
expiry date
lag Call sign/MMSI
ID Category Auto/Manual
MMSI 
Call sign 
Serial 
Customer comments
Warranty claim YES/NO
EXTERNAL
INSPECTION
Auto bracket EPIRB
Manual bracket
Magnet present 
Clip functional 
Magnet present 
Cover intact 
Lever arm operates 
HRU date________________
Tamper intact 
Plastic acceptable 
Antenna acceptable 
Lanyard OK 
Sea switch contacts 
Comments
FUNCTIONAL TEST
Sea Switch
ON within 3 seconds 
O with magnet in 8s 
Does not activate with magnet 
Self test
LED on 
Buzzer 
Strobe 3 flashes 
Live mode
LEDs/buzzer on 
Strobe consistent 
Switches off 
GPS Test
Pass 
Comments
MESSAGE READ
ID OK  Country 
MMSI/Call sign/Serial no
406 frequency OK  Man Serial No  EPIRB No Auto/Man
Comments
INTERNAL INSPECTION Required
 (optional)
Battery OK  Battery voltage______V ______V_______V
No water ingress  Plastic damage  PCB OK  No PCB corrosion 
Comments
Conclusions
Assessed by Signed Date INAL LEAK TEST RESET TIMERS
New Parts
Battery kit 
Sealing kit 
Antenna 
Lens dome 
Body 
PCB Assy 
Label kit 
/ label kit 
Pass/ ail

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3. MAINTENANCE PROCEDURES
3.1. Inspection
Manual bracket (carry safe)
If this has been returned, it should be checked as follows:
Magnet Confirm magnet is still potted into bracket and is not rusting
Release clip Check for correct and smooth operation.
R-clip should engage.
Carry safe carry safe section should disengage from main bracket.
Automatic bracket (Enclosure/Autocover)
If this has been returned, check it as follows:
Cover intact Ensure offset weight is secure.
Check cover retaining pin is present and attached to cover.
Confirm identity label on side agrees with rear of EPIRB.
Lever arm Check magnet present.
Release HRU (press down and slide upward)
Confirm lever arm moves freely and is secure.
HRU expiry date Side of HRU should be marked with expiry date.
Confirm date is acceptable.
If less than 3 months left, recommend a new HRU to customer
Confirm HRU expiry date is marked on cover side label.
Press lever arm down and refit the HRU. Ensure washer engages (section 3.10).

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EPIRB inspection
Drain holes Note that the EPIRB is designed to allow water to circulate around
the outer edge of the dome (inside the outer clear plastic edge but
outside the waterproof seal), consequently a volume of water in this
area is of no consequence. Drain holes allow this water to escape –
ensure that these are not blocked.
Tamper seal Check tamper cover/frangible tab is intact and holding switch to right.
If tab is damaged or is non-standard in any respect, battery state
must be considered suspect.
Contact customer to confirm any history of EPIRB activation.
Battery expiry If there is less than 6 months left to run, contact customer and
recommend battery replacement. If the unit is being serviced in line
with IMO Circ 1039 then you must ensure 5 years battery life.
Lanyard Lanyard should be neatly wound onto bobbin. Rewind if required.
End of lanyard shall be firmly attached to hole in rear of EPIRB.
Bobbin should clip into rear of EPIRB and remain in place.
Sea Switch Check that the sea contacts are clean and free from paint or grease.
Clean with a soft brush and IPA if necessary.
Plastic damage Check plastic body for signs of cracking or wear.
Check clear lens dome for cracking, especially around screws.
Water ingress Check if water or water vapour is visible inside the lens dome or on
the PCB.
Antenna damage Check the covering on the antenna. The antenna material is marine
grade stainless and so is resistant to corrosion however it is
recommended that the antenna is replaced is not fully covered.
Antenna should not show signs of being creased at any time.
Identity Ensure that the Identity information is clear – replace (using
programming facility) if necessary.
If the EPIRB or its mounting needs cleaning then this should be done using warm soapy
water and a damp (not wet) cloth. Do not use strong detergents or solvents.
Do not paint the EPIRB or its mounting
Do not clean with detergents or solvents
During vessel cleansing or painting remove the EPIRB and its mounting.

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3.2. Functional test
Self test
1. Press the TEST button until the red LED lights indicating that the self test is
running, then release the button.
2. The EPIRB will test its internal components and then make test transmissions
at 121.5 and 406 MHz whilst monitoring the transmitter output.
3. If all tests are successful, the buzzer will sound and the red LED and white
strobe LED will flash together a number of times.
4. If any test is unsuccessful, nothing will flash and the red LED will go out.
Operation of this test for the Smartfind Plus is identical, except that the green LED will
also flash.
The number of times the LEDs flash is an indication of the accumulated time the battery
has been in use – as long as the strobe flashes at least once then the unit has passed
self test.
Accumulated Battery Use
(hours)
Number of
flashes/beeps
0 to 4 3
4 to 6 2
More than 6 1
Expected battery use per year is 32 minutes (12 Self tests and 2 off GPS tests) – it is
recommended that any unit which has a reduced number of LED flashes should have the
battery replaced in order to ensure that the unit will operate for 48 hours in an
emergency.
Note:
The 121.5MHz transmission made during self test is unmodulated. Therefore it will
not be picked up by the ARG5 10 Mk1 message reader or by an air band radio
receiver. The self test inherently checks the 121.5 and 06 power as part of the
test. However if the 121.5MHz must be checked then a Spectrum Analyser or a
suitable EPIRB tester will be required to record the transmission.
Self test failure: See Section Fault finding
Sea switch
The sea switch contacts are gold plated and so care should be taken not to damage or
scratch them
1. Short-circuit the sea switch contacts
2. The red LED should light within 3 seconds and the strobe flash
3. Remove the short circuit
4. The red LED should go out within 8 seconds
5. Place unit into manual bracket or apply magnet to disable the sea switch.
6. Short-circuit the sea switch contacts again
7. The unit should not activate.
To avoid a live transmission the unit must not be allowed to activate for more than
50 seconds.
If the red LED starts to flash, you have made a live transmission.

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Live test
The live test detailed here is for use if a screened enclosure is not available.
It is advised that all live testing should be carried out in a screened enclosure.
1. Use a probe to push back the switch arm and then slide the switch to the ON
position.
2. Ensure that the red LED comes on.
3. Confirm the strobe flashes regularly every few seconds, the green (if fitted)
and red LEDs lights and the buzzer sounds.
4. Return the switch to the O position to switch the EPIRB off.
This must be done within 50 seconds to avoid a live transmission.
If the red LED starts to flash, you have made a live transmission.
Note that if a unit does not switch off – then it may be due to sticking reed switch.
If this is the case then a small tap onto a hard surface may release the contacts.
NOTE:
If a live transmission test is required you will need a screened box/room and
for GPS versions a GPS repeater. These tests are required for Shore Based
Maintenance testing in accordance with IMO Circ 1039. Please see 82-1039
for further details.

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GPS operation test (Smartfind Plus only)
To comply with COSPAS-SARSAT regulations, the Smartfind Plus EPIRB is also capable
of checking the correct operation of the GPS receiver. This test consumes significant
reserve capacity of the EPIRB battery, consequently it can only be performed a fixed
number of times. It is recommended that this test is performed only if the performance of
the GPS receiver is suspect.
NOTE: The green LED (indicating successful test) only lights at the end of the test while
the buzzer/strobe are flashing.
This test must be performed only in a location where the beacon may be expected to
acquire a GPS position.
1. Press the TEST button until the red LED lights, then release the button. Wait while
the Self Test routine runs, then immediately the strobe flashes press the TEST
button and hold it down for about 15 seconds until the red LED lights again. (If the
strobe does not flash, the Self Test failed. In such a case, this test cannot be
performed.)
2. Provided that the Self Test was successful, the Smartfind Plus will start the “Long
GPS Self Test” mode. The buzzer will sound twice, the red LED will stay lit and the
green LED will begin to flash. The TEST button may be released at this point.
3. This test takes 15 minutes to complete. During this time, do not shield the EPIRB
and do not stand over it.
4. If the GPS receiver acquires a position, the green LED will light continuously and
the buzzer will sound 10 times. If the receiver fails to acquire a position, the red
LED will light continuously and the buzzer will sound 10 times.
5. Whether the test passes or fails, the white strobe LEDs flash to indicate how many
Long GPS Self Test routines remain available.
NOTE: New beacons have 10 test cycles available. When the Smartfind Plus battery is
changed, it is the responsibility of the service agent to ensure that the GPS/Long Test
cycle counter is reset, as otherwise this test may not be available.
WARNING: While the EPIRB is running this test it cannot generate a distress alert. (Once
the test is complete the EPIRB returns to normal operation without any operator
intervention.)
If necessary, this test may be terminated (without performing the check) by holding down
the TEST button for approximately 5 seconds until the red LED goes out.

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3.3. Message read
To comply with SBM and annual maintenance the service provider must verify the EPIRB
message. This can be done with a "Message Reader". A typical instrument is the
ARG5410. This model will be used to describe the process. Operation of the Reader is
detailed in its handbook and will not be repeated here. The procedure is as follows:
1. On the Reader select RECV mode
2. Position the Reader approx. 1m (3 feet) from the EPIRB
3. On the EPIRB press the TEST button
4. After about 4 seconds the Reader should then beep and report DECODING
MESSAGE followed by S’TEST OK
5. The Reader will revert to its Menu. Select VIEW mode
6. Use ← → keys to view the decoded 406MHz message content
7. Confirm the frequency was within 406.020 – 406.030
This proves the 406MHz transmitter is radiating within the correct frequency band. If the
ARG5410 Reader is not used, then another facility for measuring the 406MHz frequency
must be provided (a spectrum analyser for example).
8. Confirm the 15 digit ID agrees with EPIRB rear identity label UIN
This proves the 406MHz transmitter is modulating correctly and the EPIRB is programmed
with the correct identity. If the ARG5410 is not used then another facility for message
decoding must be provided (other message readers).
9. Confirm the lag state and the Serial No / MMSI / Callsign agrees
Typical screen Q
11:25
Mesg#11 S’TEST OK
ID: 9D0D071D3B00013
06.0257 MHz PASS
Common problems
Audio tone Will not be heard with Smartfind product.
requency If outside limits, repeat self test a number of times.
(Provides a warm up time). Repeat test.
Bad frame This error message occurs if the Reader fails to synchronize.
This occurs approx. 10% of the time. Repeat test multiple
times. Move location of EPIRB/reader.
Also note that an exhausted reader battery causes bad
frames.
Normal mode
It is possible to message read in live mode provided the EPIRB is in a screened
enclosure. In this case the Reader reports NORMAL OK and the first 3 bytes of the full
hex message are E 2 … instead of the usual E D0… for self test mode.
GPS messages
The transmitted message will change once the GPS location has been confirmed. On
some older message readers this will result in a HEX ID which does not correspond to
the one given for the EPIRB under test.

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3. . Internal inspection
Internal inspection is important both for diagnosing faults and for detecting possible faults
early. Internal inspection is required under the following conditions:
• A fault has been observed and needs to be diagnosed
• If there is any indication of water inside the EPIRB
• Any salt deposit or corrosion is visible inside
• Signs of any cracking of the plastic parts
• Any time the EPIRB is opened for other reasons
Sections 3.5 and 3.6 detail how to disassemble the EPIRB and then re-assemble it.
These sections should be followed, but using the notes below as guidance on what to
look for during the disassembly process.
Prior to opening EPIRB
• Inspect lens and body for signs of levering with screwdrivers
• Inspect antenna for sharp bends, which indicate the EPIRB has been dropped.
With dome removed
• If there is a pungent smell, then suspect that one of the Lithium battery packs have
leaked. See section 1.4 for advice. Wear rubber gloves. Damaged lithium batteries
may be unstable and pose a serious safety hazard. Leakage usually damages
circuit boards, so it is often necessary to scrap the EPIRB without further
investigation.
• If the EPIRB has an electrical fault, make measurements on the battery.
• Check Sea switch contacts internally.
• Check circuit board for white salt deposits, dull grey corrosion or wetness.
If any corrosion is evident the PCB should be replaced.
• Check plastic parts, especially screw positions, for signs of cracking.
• Check condition of EMC coating inside body. Green patches mean water ingress.
With battery removed
• Check condition of weight. Green deposits mean water was present