Summary of CM2
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User manual the cm2 sidescan sonar system (all configurations except those using maxpro software) issue 3.6 © c-max ltd 2008.
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Cm2 sidescan sonar user manual version 3.6 (2008) ii.
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Cm2 sidescan sonar user manual contents contents (also see bookmarks if viewing pdf version) 1. Summary of warnings ………… 1 2. System components ………… 2 towfish sonar transceiver (str) c-shell c-case 2 c-case se tow cables accessories specifications 3. Installing the system ………… 6 data acquisition sub...
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Cm2 sidescan sonar user manual contents 12. Repair and replacement ………… 23 replacing the towfish pcb replacing a transducer repairing the tow cable replacing the safety lanyard servicing the surface electronics servicing the str servicing the c-shell servicing the c-case 2 servicing the c-case se 13...
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Cm2 sidescan sonar user manual 1. Summary of warnings 1. Summary of warnings the warnings summarised here are intended to prevent injury to personnel and equipment in what can be a hazardous environment. Operators of this equipment are responsible for their own safety the supplier accepts no liabili...
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Cm2 sidescan sonar user manual 2. System components 2. System components towfish the towfish is the acoustic sensor head. It transmits a very high frequency acoustic pulse (“ping”) at regular intervals and receives the series of echoes that result from each ping. Towfish and tow cable terminator thr...
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Cm2 sidescan sonar user manual 2. System components c-shell the c-shell is an optional polypropylene clamshell enclosure for the str. The c-shell converts an str into a fully waterproof (ip67) unit, complete with waterproof connectors. The str can be quickly fitted or removed. C-shell, panel and con...
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Cm2 sidescan sonar user manual 2. System components c-case 2 c-case 2 is the first successor to the earlier version that ran maxpro (under dos). It is an all-in-one data acquisition unit with an integral pc, designed for use in the exposed environment of an open boat. It uses maxview or third-party ...
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Cm2 sidescan sonar user manual 2. System components c-case se the c-case se is also an all-weather data acquisition unit. It takes advantage of the availability of ruggedized laptop pc’s such as the panasonic toughbook series to eliminate the need for the under-panel integral cpu as fitted to the c-...
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Cm2 sidescan sonar user manual 3. Installing the system 3. Installing the system data acquisition subsystem the cm2 system uses a pc, running microsoft windows, to acquire and display the sonar records. The user normally supplies this pc. To install the acquisition software on this pc see the maxvie...
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Cm2 sidescan sonar user manual 3. Installing the system tow cable put adhesive tape markers on the tow cable, a few metres above the terminator, to warn when the towfish is close to the vessel. Installing a winch and pulley (if used) the tow cable should run directly from the top of the winch drum t...
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Cm2 sidescan sonar user manual 3. Installing the system attaching the safety lanyard and tow cable extension first remove the drop-nose pin from the rear of the keel, feed the loop of the safety lanyard into the end of the keel, and replace the pin to secure the loop. Drop the nose of the pin, to 90...
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Cm2 sidescan sonar user manual 3. Installing the system attaching the towing bail checking system operation with the whole system now connected as described earlier in this section, apply power to the str, c-shell or c-case. The red power indicator should light. If maxview has been installed, open i...
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Cm2 sidescan sonar user manual 3. Installing the system the connecting… message indicates that the towfish has started its initialisation and that the tow cable telemetry is being set up. This message should disappear when the telemetry link has been established and the towfish has started running. ...
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Cm2 sidescan sonar user manual 4. Planning the survey 4. Planning the survey survey plan every survey or search needs to be planned in advance. Survey planning and post-processing are topics that are wider than can be covered here. Most sonar acquisition software packages, including maxview, include...
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Cm2 sidescan sonar user manual 4. Planning the survey in order to identify a target, or to provide extra assurance of coverage, it may also be necessary to follow the along-current lines with a set of perpendicular, cross-current, lines. Sometimes the major consideration in planning lines is not the...
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Cm2 sidescan sonar user manual 5. Operating the towfish 5. Operating the towfish pre-launch check check that the towfish transducers are angled high or low, as required, as indicated by the yellow dots on the depression adjuster cam. Adjusting the transducer depression angle check that the tow cable...
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Cm2 sidescan sonar user manual 5. Operating the towfish using the wing depressor if the optional wing depressor is used, refer to section 18 for advice and important warnings. Launch launch the towfish astern with the vessel preferably at slow speed. Do not allow any slack in a winched tow cable dur...
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Cm2 sidescan sonar user manual 5. Operating the towfish as soon as the altimeter has locked to the bottom and the image is normal, wind the cable in or out, or adjust speed, until the towfish flies at an altitude equivalent to 5 -10% of the range limit. The towfish must be flown high enough to clear...
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Cm2 sidescan sonar user manual 6. Operating guidelines 6. Operating guidelines do not allow the towfish to hit the bottom – be very careful when turning fly the towfish on as straight a course as possible, to prevent distortion and smearing of the image fly the towfish lower (but safely clear of the...
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Cm2 sidescan sonar user manual 7. Notes for the helmsman 7. Notes for the helmsman navigation use the sonar's plotter window to show waypoints, the track and the swept ground. Steering the quality of the sonar images depends on the skill of the helmsman. This applies especially to the hf and ef oper...
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Cm2 sidescan sonar user manual 8. Towfish commands 8. Towfish commands towfish command set the cm2 towfish uses the same set of commands regardless of what acquisition software is being used. Towfish start, stop, range selection and bottom-tracking control must be supported by all acquisition softwa...
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Cm2 sidescan sonar user manual 9. Interpreting the sonar image 9. Interpreting the sonar image (this topic may be covered in additional detail in help text associated with maxview or with third-party acquisition software.) typical sonar image (780khz) water column and bottom image at the very centre...
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Cm2 sidescan sonar user manual 9. Interpreting the sonar image if an object casts a shadow on a flat bottom the height of the object is given by simple geometry, using the shadow length, the towfish altitude, and the true (slant) distance of the object from the centreline. Some acquisition software,...
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Cm2 sidescan sonar user manual 10. Routine maintenance 10. Routine maintenance routine maintenance maintenance is simple and is normally limited to the following tasks: - (a) immediately after use, thoroughly wash the towfish with fresh water if it has been exposed to seawater: also wash the tow cab...
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Cm2 sidescan sonar user manual 11. Storage and transit 11. Storage and transit keep the towfish transducers from becoming excessively hot by keeping them out of direct sunlight. The system should be stored and transported in purpose-designed containers. Internally padded shipping/storage cases can b...
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Cm2 sidescan sonar user manual 12. Repair and replacement 12. Repair and replacement replacing the towfish pcb the towfish internally contains only lead ballast and a single printed circuit board (pcb). This pcb can be replaced as a unit by the user. Note that this pcb is complex and is not user-ser...
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Cm2 sidescan sonar user manual 12. Repair and replacement whenever the rear bulkhead (or the nose) has been removed the end of the tube is vulnerable to damage. Even a short drop on to a hard surface may distort the bore. To remove the pcb, first disconnect all attached connectors. Then remove the m...
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Cm2 sidescan sonar user manual 12. Repair and replacement if a lanyard must be constructed locally in emergency, it should have an internal length, measured over 8mm pins, of 98.5cm. Servicing the surface electronics some items are sensitive to electrostatic damage and must be handled accordingly. B...
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Cm2 sidescan sonar user manual 13. Troubleshooting 13. Troubleshooting str or c-case will not power up check the supply voltage. Towfish will not start wait 30 seconds before trying again. Check all connectors. Use a dc voltmeter on pins 1 and 2 of the underwater tow cable connector (disconnected fr...
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Cm2 sidescan sonar user manual 13. Troubleshooting winch does not operate check the supply voltage and polarity. Check the operation of the remote control pendant using an ohmmeter between the common and in and out contacts. Other troubleshooting advice if further advice is required, consult your lo...
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Cm2 sidescan sonar user manual 14. Interfaces 14. Interfaces towfish/tow cable interface wet end interface mechanical: cm2 terminator, bail arm assembly and tow cable extension electrical: subconn micro 3 female (or equivalent) data = pins 2 and 3, polarity not significant; balancing signal (in tow ...
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Cm2 sidescan sonar user manual 14. Interfaces c-case se interface tow cable or winch deck cable mil-c-5015, size 14, threaded, 4-way bulkhead connector sockets a and b; polarity not significant power input input (see c-case se specifications for power requirements) mil-c-5015, size 14, threaded, 6-w...
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Cm2 sidescan sonar user manual 15. Specifications 15. Specifications towfish specifications operating depth 0-2500m acoustic frequencies 100khz -lf 325khz –hf (compatible with industry “500khz” specs) 780khz -ef ranges (port and starboard) 100m,150m, 200m,300m,400m,500m –lf; 25m, 50m, 75m,100m,150m ...
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Cm2 sidescan sonar user manual 15. Specifications c-shell specifications the c-shell provides a waterproof housing for an operating str, with waterproof external connectors. It also has an internal location for a dongle for the acquisition software. Interfaces tow cable, usb, dc power dimensions (mm...
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Cm2 sidescan sonar user manual 15. Specifications tow cable specifications tow cable, types available coaxial or twisted pair; circuit resistance 200ohm max. Tow cable diameter options 11.4, 8.2, 6.4 or 4.7mm, stainless steel armoured 8mm "soft", polyamide reinforced, pu sheathed custom cables also ...
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Cm2 sidescan sonar user manual 16. Cm2-win-300 winch 16. Cm2-win-300 winch introduction the purpose of the optional cm2-win-300 portable winch is to handle 4.7mm diameter, steel-armoured tow cable. This type of cable cannot be handled manually. The cm2-win-300 portable winch was introduced in 2006, ...
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Cm2 sidescan sonar user manual 16. Cm2-win-300 winch temperature alarm later units are fitted with an audible temperature alarm. The alarm is intended to protect the winch motor from excessive temperatures, particularly when recovering cable with the towfish fitted with the optional wing depressor. ...
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Cm2 sidescan sonar user manual 16. Cm2-win-300 winch recess; some force may be required. If the slip ring unit is accidentally pulled out of its recess during this process, secure it again afterwards with flexible silicone sealant. Remove the 4 m6 fasteners holding the bearing support assembly to th...
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Cm2 sidescan sonar user manual 16. Cm2-win-300 winch accessing the winch drive components the winch drive components include the integrated motor-gearbox unit, pair of switching relays, soft-start module and its power transistor, cooling fan, and motor temperature alarm. These are all accessible ben...
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Cm2 sidescan sonar user manual 17. Sk172 & sk172e winches 17. Sk172 and sk172e winches freeing the drum in an emergency on the optional sk172 and sk172e portable winches, an extended 5mm a/f key can be used to release the winch drum for hand rotation in an emergency, by unscrewing the two locking sc...
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Cm2 sidescan sonar user manual 17. Sk172 & sk172e winches replace the flange in the end of the drum, and fit the end bearing plate. Rotate the winch several times to position the cable firmly around the drum. Then seal the cable exit slot using silicone rubber compound. The control pendant connectio...
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Cm2 sidescan sonar user manual 18. Wing depressor 18. Wing depressor introduction the tow cable of a sidescan sonar is subjected to significant drag forces at normal survey speeds, causing the towfish to rise. Therefore more cable must be veered or the tow speed must be lowered in order to keep the ...
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Cm2 sidescan sonar user manual 18. Wing depressor launching the towfish and wing use the handle at the end of the wing when initially lowering the towfish. The wing handles can also be used when reaching for the towfish to recover it. Be aware that the wing can cause the towfish to glide forward on ...
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Cm2 sidescan sonar user manual 19. Pulleys and counting pulleys 19. Pulleys and counting pulleys pulley types there are two sizes of the pulley designed for use with cm2 tow cables. These are snatch-block types; the pulley does not need to be disassembled to fit or remove the cable. There are also t...
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Cm2 sidescan sonar user manual 19. Pulleys and counting pulleys pulley cable guides counting pulley the purpose of the counting pulley is to allow the tow cable scope (i.E. The length currently deployed) to be displayed to the sonar operator and be recorded within the sonar record. Note that the cab...
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Cm2 sidescan sonar user manual 20. Polemount bracket 20. Polemount bracket introduction some users prefer to use a rigid overside mount for the towfish in certain circumstances, instead of towing it. The advantage is that the towfish is not endangered when manoeuvring in restricted depths or near ob...
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Cm2 sidescan sonar user manual 21. Usbl transponder bracket introduction where accurate tracking of the position of the towfish is required, c-max recommends the use of an ultra- short-baseline (usbl) acoustic tracking system. Suitable usbl systems are available from several manufacturers, and shoul...
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Cm2 sidescan sonar user manual 22. Towfish sensors heading and depth sensors the towfish heading may be different from the direction of the towfish track if there is a cross-current. Heading information, if available, may be used to correct the apparent location of targets by compensating for the ya...
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Cm2 sidescan sonar user manual towfish depth sensor the optional depth sensor may be already installed in the towfish when delivered or may be retrofitted in the field. The sensor is moulded into the rear bulkhead, so retrofitting requires the bulkhead to be replaced. The bulkhead and towfish pcb sh...
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Cm2 sidescan sonar user manual 23. Rov and auv configurations 23. Rov and auv configurations rov configurations the cm2 system is suitable for use on remotely-operated vehicles (rovs). In place of the towfish in a towed system, the “sonar head” consists of the acoustic transducers and an rov bottle ...
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Cm2 sidescan sonar user manual 24. Warranty scope cm2 components manufactured by c-max are warranted for a period of 36 months from the date of dispatch. Winches from third-party suppliers, all cables and all other items are warranted by c-max for satisfactory operation for a period of 12 months fro...