Smooth Operation Page 2
By Capt. Ken Kreisler — January 2002
In the world of electronic signals, all this happens so quickly that, for example, if you’re going in reverse and need to bump the boat forward, your command is obeyed almost instantaneously. Lag time is virtually nonexistent after initial startup. And because there’s no cable to push or pull, the action is smooth and effortless.
There are two ways this works. First, with nonelectronic engines, the control system is interfaced with the mechanical governors and shift mechanisms via servomotors. These motors in turn operate the engine functions. With the newer, fully electronic engines, there is no need for servomotors, as everything is fly by wire.
But how foolproof are these new gizmos? "If there’s a loss of power to the system, it will not continue to operate and will basically stand fast," Turner says. This means the unit will drive back to neutral idle to avoid damaging the engine or transmission. "There has to be a valid range of voltage to keep the system from defaulting," he adds. "We have our own parameters for this, and so do the other manufacturers."
Turner explains that the microprocessor has the capability to run a series of diagnostics on itself to see how it’s doing, once again at lightning speed. It even has something he describes as a watchdog timer. "What this does is alert the microprocessor that something is going awry and sends the system into default, and the fault indications can be through beeps or a series of blinking lights," he says. Depending on the severity of the problem, the microprocessor can automatically turn down the rpm to, let’s say, 1000 until the problem is fixed. Or if need be, it can send the engine right to neutral idle.
How do you get around this problem of power loss and default modes? Basically, you don’t. On the one hand you’re at the mercy of technology, but on the up side, given the sophistication of the systems and their components, the odds are in your favor.
This article originally appeared in the June 2003 issue of Power & Motoryacht magazine.