Features July 1, 2003 Issue

Integrated Instrument Systems

Installers we asked appreciate the simplicity and track record of the Raymarine ST60 series. In a fast-changing electronics world, that's a big advantage. However, most other instrument-makers also have strong products. The trick is to find skilled installation and support.

At some point, one or more of the instruments you installed 10 years ago, or that were on the used boat you purchased, will be on their last legs, and it will be time to shop for replacements. Or maybe it's just time to move beyond that stand-alone depthsounder and into the wonderful world of integrated electronics. OK, maybe it's not always wonderful, but it's a world. 


Either way, you'll probably find evaluating new gear a real eye-opener. In only one generation, sailing instruments, coupled with GPS position-finding, have evolved from Walker logs, sextants, compasses, and chronometers to complete push-button analysis of depth, wind, and current character, and what to do about it. It's the equivalent of going from tin cans tied to a string to the cellular telephone. Since our last instrument review (May 1999), companies have introduced instruments so sophisticated that most sailors don't learn all of their functions.

Add the significant price-drop of many components, and even the most budget-conscious sailor can contemplate owning sophisticated, precision instruments.

Beyond their ability to provide data that allows a sailor to avoid hard spots under the surface and plot courses based on speed measurements, new tools increase the ability to move efficiently from point A to point B. Along the way, they also can increase enjoyment of the sport by allowing skippers and navigators to acquire data allowing them to take advantage of the elements—wind speed, wind direction, and current, for instance. Big-boat racing sailors have long known this, but today more cruising sailors are interested in coupling wind information with boatspeed and GPS positioning in order to improve their boats' performance.

Integrated Information
The foundation of any system is still built upon speed and depth instruments, which may be purchased and installed individually. In general, however, it makes economic sense to purchase a 'starter kit' from a single manufacturer. That way, you're better assured that the hardware is compatible and the data will flow smoothly.

More than that, unless your boat is so small that you can't imagine ever expanding, your best bet is to plan for your ultimate needs at the outset and purchase a system that allows the addition of building blocks. "Never say never" is a good approach in the electronics world.

The common components of a basic integrated system are an anemometer and display for windspeed and wind angle, and a knotmeter/log. Most boats also carry a GPS receiver, whose data can usually be fed into the displays.

The run-of-the-mill wind instrument measures only apparent wind. Measuring true wind speed and angle from a moving platform is a bit trickier, and that's what requires the gathering of sensors and components: True wind data must be calculated from the relationship of the apparent windspeed and angle with boatspeed. With wind and speed instruments linked, VMG (velocity made good) can be determined. Note that this definition of VMG is related only to the boat's progress directly upwind or downwind; it's not the VMG referred to by position-finders like GPS, which mean velocity made good toward a waypoint, over the bottom.

With the addition of a fluxgate compass to feed the boat's magnetic heading into the mix, even more information can be gathered, like true wind direction.

Since a speedo measures the speed of water flowing under the hull, rather than the boat's speed over the ground (SOG), and a compass measures a boat's heading rather than its course over the ground (COG), neither accounts for local influences like current set and drift or leeway. Link up the GPS to adjust for that.

Integrating all of those functions produces a universal picture of your boat in the the elements, and allows you to test your mettle by comparing your sailing performance to your boat's potential. A fully integrated system absorbs all of the data produced by wind and speed instruments, fluxgate compass, and GPS, to produce a wealth of data that can be interrelated in all sorts of ways.

Using the Data
A traditional rule of thumb is that a displacement sailboat's theoretical hull speed is 1.34 times the square root of the waterline length. In practice, boats can go faster or slower than that through the water, because of local effects. We usually think of a broad reach as a boat's fastest point of sail, but it's important to remember that a boat has maximum theoretical speeds at all points of sail and in all windspeeds. These theoretical speeds are determined today by Velocity Prediction Programs (VPPs) and can be expressed in the form of polar diagrams, a.k.a. polar plots, a.k.a. "polars." The optimum speeds are found along plotted performance curves in relation to the axes of wind angle and windspeed.

You can integrate your polars with the data from your instrument system and GPS to produce a complete picture of your performance, relating your theoretical maximum speeds to your actual performance and producing "target" speeds, which are related to your VMG on a racecourse...Sound confusing? In simple terms, it's a continuous, immediate report card.

If you're interested in learning more about the science of sailing, including simple but rarely understood concepts like "velocity headers," and even more elegant concepts like "Wallys," read the Ockam U Seminar Manual, available for $25 (www.ockam.com). It's written by some of the smartest sailors in the game, and may well introduce you to the boffin and speed-demon within. It's a Best Buy for the cerebrum.

In any case, since the software engineers have saved us the labor of sitting down below, drawing lots of vector triangles, the most difficult task becomes learning to calibrate and operate the instruments.

How They Work
Before evaluating the specific functions of any instrument system, it's important to understand the operational differences. First-generation instruments were round, had analog displays, and were individually wired to power sources. These days, most instrument packages are driven by software that allows them to input and output data from external devices; GPS, autopilot, and radar, for instance. Readouts are analog, digital, or both. Two configurations are common: those run by a CPU, and those utilizing a distributed processing system commonly referred to as a daisy chain.

Manufacturers say the primary advantage of the CPU is that information is passed more quickly between instruments; the downside is that if the CPU fails, the entire system may fail. A distributed system connects a series of instruments that operate independently. In both cases, a multi display allows readings from several units to be displayed on one screen. It's akin to switching from one software program to another at the click of a mouse.

An important criterion is that a system is able to input and output language in an NMEA 0183 code. A standard developed by the National Marine Electronics Association, NMEA connections allow components purchased from different manufacturers to communicate; its absence may require the purchase of an interface tool when adding components. (See the PS Advisor for more on this.) Raymarine's SeaTalk, for example, allows all of that company's instruments and autopilots to communicate; however, they may not understand another manufacturer's codes. Though not a poison pill, it's an inconvenience and added expense.

Equipment should be evaluated on the basis of the current NMEA software; Simrad's IS systems are current through versions 1.0 - 3.0, for instance. NMEA 2000 is a proposed protocol that is now going through industry beta-testing. Some manufacturers are already building equipment based on the proposed specifications.

Finally, once needs have been identified, before purchasing any system, consider the physical space in which displays, repeaters, and junction boxes or a CPU will be located.

The Companies
As the marine electronics industry matures and its face changes, it's becoming more difficult to tell the players without a scorecard.

Since our 1999 review, KVH has discontinued production of its popular Quadro system to focus on the development of satellite receivers for military and recreational use.

Nexus Marine, distributor for the Nexus 3000, our Best Buy package, ceased operation. Nexus instruments are still manufactured in Sweden by Silva. The North American distributor for Silva is ComNav Marine Ltd., a privately held Canadian company that has been producing navigational equipment since 1983. Silva/Comnav is about to introduce the NX2, a CPU-driven system that's a step up from the Nexus 3000.

Raytheon Marine Company, a division of Raytheon, became Raymarine in January, 2001, following a management buyout in which six managers and a venture capitalist purchased the division from the parent for $108 million. The new company builds Pathfinder radar, Autohelm autopilots, Raychart navigation systems, and Raymarine instruments. Its headquarters is in the UK; sales and engineering operations are in Nashua, New Hampshire, and Fort Lauderdale.

Similarly, the Navico brand was purchased by Simrad, which markets Simrad IS12 and Simrad IS15 instrument systems.

Amidst the shuffling, Navman, founded in New Zealand in 1987 under the name Talon Industries, purchased the Navman trademark in 1994. In 1998 the company developed their own GPS receiver, and expanded into the marine market. The company formed Navman USA in 2001, and entered the US market with products that are being well accepted. Corporate headquarters is in Nashua, New Hampshire.

From a purchaser's standpoint, the situation could not be more positive. The industry has evolved to the point that most manufacturers are producing a vast array of comparable, reliable, compatible navigational equipment. Manufacturers are building to NMEA standards that allow the integration of instruments from various manufacturers. Tremendous competition is producing generally stable systems and falling prices.

Instrument Systems
At one end of the price and function spectrum, Raymarine's ST60 maintains the largest market share for several reasons: the company's products are now being installed as standard equipment at the factory by many manufacturers; the system is an excellent replacement for old equipment; and the equipment is engineered and priced for the mainstream market.

At the other end of the spectrum, Ockam's instruments and software range from a cafeteria of basic functions ($6,600) to systems so sophisticated ($20,000+) that they are found on the majority of America's Cup and maxi racers. Comparing the company's products to off-the-shelf systems would be akin to comparing an E- scow to Endeavour. Ockam is the Rolls Royce in its segment of the industry.

In the middle, B&G's H1000 system, Simrad's IS15 and IS12, Conmav's Nexus and NX2, Navman's 3100 series, Signet Marine's SmartPak system, and NKE's Topline Bus systems offer the gamut of functionality.

What They Do
Like plain vanilla, the Raymarine ST60 system offers everything from stand-alone display units to fully integrated systems with repeaters, remote controls, and flexible mounting options. Operation is by pushbutton controls. When coupled with a GPS, SOG may be displayed. True wind measurements require the addition of SeaTalk, a plug and play cable system that integrates other Raymarine navigational aids. The downside is that the addition of other manufacturers' products requires an NMEA adapter.

Purchase of a Tridata unit ($635) provides depth and speed readouts on a single, three-line display. A windspeed indicator ($1,020) adds an analog and digital readout of apparent and "relative" wind. Only the addition of SeaTalk and GPS produces true wind, so the system isn't as inexpensive as it first appears.

To attract the more sophisticated buyer, the company recently introduced ST290 instruments, a network-based system operated by a data-processing unit using the updated SeaTalk2, which Raymarine claims transfers data 20 times faster than the competition. The system integrates autopilot and heading with depth, speed, and wind measurements to provide information necessary for precise navigation and performance. Split screens display digital and graphical data, and cross-track measurement compares correct versus actual course sailed. Base price for speed and depth with graphic display is $2,390; add $590 for a wind instrument. The Raymarine dealers and installers we spoke to were receptive to the new system, but seemed to take a "wait and see" approach before commenting on it in depth.

Since the Nexus 3000 earned a Best Buy in 1999, dealers and installers continue to recommend the product. The most common comment is "a lot of features for the money." Equipped with a Multi Control that displays readouts from each of four transducers hooked to a server, and liquid- damped fluxgate sensor on the compass, the package is competitively priced at $1,450.

John Josephson of ComNav says the advantage of the 2003 NX2 series is the display of 40 functions on the Multi Control display, two NMEA ports, an updated central processor, and digits on the display. NX2 start packs range from $999 for basic speed and depth, to $2,199 for speed, depth, windspeed, and compass. A plus is that all of the Nexus systems include transducers in the base price.

An option is the NX2 Wind Data instrument ($499) which displays up to five fields simultaneously, including boatspeed, apparent and true wind speed, apparent and true wind angle, target boatspeed, VMG, bearing to waypoint, and when to tack or jibe. That's high-tech information and low-tech pricing.

B&G's (Brookes & Gatehouse's) basic line of integrated instruments, called B&G Network, is familiar to many sailors. This package is sold via the big chandleries and is a solid, proven system with easy-to-read-displays. It's probably the mainstream competition to Raymarine's ST60 system. B&G's Hercules 2000 and Hydra 2000 series are aimed more at racers, while their newest system, the H1000 (introduced in 2001) is a daisy chain development, designed to make it easy to add and configure components. The H1000 system can display all of the system's information, a by-product of interface boxes connected by a single-cable high-speed data link the company calls the Fastnet 2.

The basic S2 package ($1,050) includes the multi-display, speed and depth; S2N ($1,300) adds an NMEA universal interface; S3N ($2,299) adds windspeed, and S4N ($2,799) a compass.

To fully evaluate B&G's price, compared to competitors, it's essential to closely evaluate a list of the functions in each package. The S4N contains a list of 35, including tidal set and drift, water temperature, ETA, and header and lift trends.

Navman is still in the early stages of the development of a distribution system. Nonetheless, retailers and installers who are marketing the products consider it a winner.

The company's Yachting 3100 series consists of individual units that may stand alone, or be integrated by use of a NavBus, an NMEA-compatible system that allows connection to multi-displays operating off one set of transducers. Except for a "locked-angle" function that allows a helmsman to steer to a pre-selected wind angle, the system's laundry list of functions is similar to its middle-of-the-road competitors. A plus is variable damping in the speedo that improves the accuracy of readings, and a trim speed function that displays fluctuations above or below target speeds.

As one retailer told us, "prices are 20 percent below the competition."

Components are priced individually. The Multi unit retails for $399; speed, $269; depth, $269; and wind 3100, $429. At $1,366 the system is competitively priced.

Similarly, Simrad's IS15 system consists of digital heads that the company's Tom Burke says "are best considered tactical information centers, as they can display virtually any and all NMEA 0183 information supplied to them from other devices."

In many cases, adds Burke, "A stand-alone NMEA repeater system will utilize transducers already on the vessel."

When Simrad purchased Navico in 1998, Navico was marketing Corus, which utilized a proprietary bi-directional network language, and Simrad was in the process of introducing IS15. Eventually, Corus disappeared, and IS15 became the company's flagship instrument system. Dealer feedback indicates that, in the company's rush to enter the market, it introduced systems with software bugs so troublesome that dealers began selling other brands.

"In many cases, software repairs were available via download, but the company only told us about the fixes after we had complaints from customers," one dealer said.

As a consequence, another dealer said, "Simrad has struggled to reacquire market share in a competitive market, despite having resolved the software issues. They do have a good product."

The minimum cost of a full single-head IS15 system, with its own transducers, displaying windspeed, boatspeed, depth, water temperature, and containing one NMEA  input or output port, is $1,746. However, as Burke points out, a budget-conscious owner could build a less expensive system. "The IS12 system is composed of dedicated digital heads, so transducers may be plugged directly into them." A two-head system providing wind angle, boatspeed, depth, and water temperature costs $1,560.

NKE Marine Electronics were actually the first to create an integrated electronics system, called the Topline BUS. In the last 12 years they've been quietly upgrading that system following two changes of ownership of the French company in 1998 and 2001. Their long-time U.S. distributor, Euro Marine Trading, provides sales and service in the U.S. and Canada.

The system can be composed of as many displays as necessary (they have five types and sizes, plus complete analog displays), all receiving data direct from the five main speed, depth, wind, compass, and GPS sensors, as well as a wireless remote control with MOB function.

According to Tim Robinson of Euro Marine Trading, the main sensors in the NKE Topline system are "smart" sensors. "The data coming out of these is already BUS data, able to move through the system. So the principle is that there's no 'brain' or black central box to convert data—it's already converted at the sensors.

"The BUS cable is a single cable with three wires inside—voltage, data and ground—and moves throughout the boat and through junction boxes where splitting is needed. So when you get a display or sensor, there's only one wire coming out of it. You can pick whatever display you want to be the master, and make changes in the system through that one display."

MSRP for NKE's Digital Wind Package, which includes the package with knotmeter/log and depthsounder, is $1,895. The top-of-the-line Race Package is listed at $4,195.

Signet Marine's SmarkPak Systems also offer an integrated, expandable system centered on a Base Module the company refers to as the "Speed/Depth SensePak" (SL 175), which costs $985. Beyond basic functions, Signet, like several of the other instrument-makers, adds sea temperature to boatspeed and depth, as well as a clock and racing timer. These are all connected via a 10' bus cable to a rectangular display. The system can be expanded to three higher levels, first with a Wind SensePak, which gives apparent and true windspeed and angle, and VMG (add $1,095, for a total of $2,080), then to a Performance SensePak with fluxgate compass, then to a Navigation SensePak, which incorporates GPS and all its attendant functions.

Obviously, it's important to be able to read displays in varying levels of light and contrast, and while wearing sunglasses. All of the manufacturers have improved their products significantly since the introduction of the first LCDs, by producing larger, darker digits, higher resolution, and better backlighting. The improvements are similar to those in the computer and automobile manufacturing industries.

Practical Sailor was unable to line up displays from all manufacturers side by side for this market scan. However, based on the experience of sailing with various displays in recent years, and of scrutinizing them at boatshows, we would hazard the statement that there are few radical differences in the general viewability of the displays. There are, however, differences in the style of data presentation on the screens—black on green, black on red; all digital versus a combination of digital and analog; big digits in one line, smaller digits in two lines; levels of backlighting, and so on. Many of these features are user-adjustable; some are not. The only way to find out which combinations suit your eyes best is to go to a boatshow or a marine electronics display and familiarize yourself with the options.

Except to provide a frame of reference, prices in this article may be misleading because of the typical wide gulf between MSRPs and discounted prices. Even more important, to analyze price differentials most effectively, the total cost of a system must be based on the additional cost of accessories necessary to complete hookups, and the cost of installation if you're not doing it yourself.

Beyond the base units, you will find charges for additional displays; fluxgate compass, which may require a GPS; cables, based on diameter and length; transducers; NMEA ports; antennas; mounting brackets, and fasteners.

Since current instrument systems offered by mainstream manufacturers are performing most of the same functions, determining which system to purchase becomes a daunting task. Given the corporate spasms experienced by some of these companies in recent years, it seems to us that cruising sailors with casual racing aspirations would be wisest to stick for now with known quantities—Raymarine's ST60 and B&G's Network certainly have an established record, and it's a mark of success that production boatbuilders have so often specified them in their instrumentation package options. It has to do with cost to the builders, surely, but also with warranty work: The builders don't want to be fielding complaints in this area.

On the other hand, as we've learned from the installers, the hardware and software of the long-established lines from all these makers are pretty well nailed down these days. The big trick is to think through how much information you really need, and where to put it, especially if you're considering expanding in the future.

Another serious concern is customer service and tech support, at both the installer and customer level. While Raymarine's ST60 is a trusted system, the customer might not receive the same intimate level of support from Raymarine, day to day, as would be likely from Euro Marine Trading, the sales and service agents for NKE in North America.

As for total expense, the boatowner assumes a big risk when buying an integrated system through a chain discounter, concentrating solely on the price tag. An electronics technician who represents several manufacturers will almost invariably provide more useful information than a sales associate working for one of the major discounters, as we've seen many times over the years. None of the sales associates we talked to when researching this article was able to provide more information than is contained in a printed catalogue or available on the web, except for his or her store's selling prices. In one instance, because his catalogue did not contain information on Raymarine's new ST290, an store salesman told us, "The product has been discontinued." He then backtracked, provided Raymarine's 800 number, and said he'd place the order if we could find the product.

In comparison, an experienced retail specialist or installer will spend more time attempting to match an instrument system to your needs and budget.

Another risk when buying from a non-specialized retailer is the likelihood of purchasing the wrong accessories for main units. "It's not unusual for an owner to deliver a box to us that doesn't have the right parts," one installer told us. Though the major loss in that situation is time and postage, errors like that are a big aggravation.

It's true that a 6-10% savings in the purchase price of a system can amount to real money, as long as all goes smoothly afterwards. However, the savings may disappear if the units don't work properly. A professional installer will check the equipment when it arrives, and deal with shipping or warranty problems. When products are not purchased from installers, they typically charge for time and material for an installation. So, though a defective instrument may be replaced or repaired at no cost, the risk is paying twice for the installation.

An installer will take charge of the setup and calibration of the system. In most cases, instruction manuals are suitable for the task; however, as one installer said, "Most are tossed in the chart table and never read." And as one discounter told us, "We sell equipment—we don't give lessons."

Finally, in this corner of the marine gear world, it rarely pays to be an early adopter (read: guinea pig). A frequent comment among installers is that "the companies don't spend enough time beta-testing the units before bringing them to the market." So if you like being in the avant garde, at least avoid the temptation to lead the charge.

Properly installed and calibrated, any of the systems mentioned here will provide all the information most skippers will need. Some people will want more data simply because it can be produced, but really, there's little sense in buying more than you need to heed, especially if you're not racing or even in a hurry. And rest assured, there will probably always be a "new new thing" in this gear category. See PS Advisor for word of Furuno's NavNet and the Raymarine hsb2 network.


Also With This Article
Click here to view "Greater Than the Sums of Their Parts."
Click here to view "Instrument Systems: Installer Comments."

B&G, 727/540-0229, www.bandg.com
ComNav Marine (Nexus), 800/428-0212, www.comnavmarine.com
Navman USA, 866/628-6261, www.navmanusa.com
NKE, 800/222-7712, www.euromarinetrading.com
Ockam Instruments, 203/877-7453, www.ockam.com
Raymarine, 800/539 5539, www.raymarine.com
Signet Marine, 310/320-4349, www.signetmarine.com
Simrad, 954/922-7700, www.simradusa.com

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