Electronics wiring question

[kirk a]

On my 330, there is a suite of Raymarine instruments. One of the components was a DSM 300 which has been replaced with a CP 370 for driving the transducer. The wiring for the prior system had all the other components wired to the fuse panel, except for the DSM 300, which was wired to the end auxiliary rocker switch. In course of adding a second display, I noticed there was no room in the existing fuse panel for both displays.

My suspicion is the lack of room was the reason the DSM was wired to the auxiliary switch. I'm adding a second fuse panel - is there any reason not to move the hot lead for the new CP 370 to the new fuse panel, from the auxiliary switch?

 

[DennisG01]

No, that would be fine. But you could just add an inline fuse and skip adding the new fusel panel.

 

[wspitler]

Some are of the opinion that transmitting sonar when out of the water can damage the transducer. Placing the DSM300 on a separate switch would allow sonar to be easily turned off, saving battery power and keeping the transducer cool out of the water. There could also be load sharing issues with the entire power bus. Make certain the buss wires and fuses are properly sized.

 

[kirk a]

Thanks - that makes perfect sense, and I'll keep it rigged that way.

 

[DennisG01]

That's a good point about being out of water, Bill. I've always heard that, too. Although I don't know how long it would take to heat up. I've had it on for about 5 minutes many times - and on many different boats - and never had an issue. I suspect it would take quite a while to heat up - but I have zero knowledge on how long is too long. Obviously, if one anticipates using things out of the water, then it's certainly safer to have a separate power switch. Every boat I have ever seen that has a stand-a-lone depthfinder always has it's own switch. But I believe my DSM300 only turns on if it I turn the chartplotter on?

 

[Halfhitch]

If you are viewing your plotter/sounder for a good while, just a couple of clicks in the menu and you can turn off the sounder.

 

[SkunkBoat]

Some are of the opinion that transmitting sonar when out of the water can damage the transducer. Placing the DSM300 on a separate switch would allow sonar to be easily turned off, saving battery power and keeping the transducer cool out of the water. There could also be load sharing issues with the entire power bus. Make certain the buss wires and fuses are properly sized.

I was going to say that! Even though it is a 330 with bottom paint, not a trailer boat.

But actually, I wish the Garmin MFDs would have an easy to find transmit sonar on/off. Its always multiple layers deep in the menu. Hell, it should default off and at startup ask "Transmit Sonar?" The radar has a Xmit on/off icon right on the screen. When I'm on blocks in the off-season, I want to use the Garmin MFDs and not transmit sonar in air. I have a 1kw and a 2kw transducer. Yes you shorten their life if they are not cooled.

 

[kirk a]

Dennis - you may be right that the DSM only comes on once the MFD tells it to. However, the DSM has it's own power cable so whether or not the MFD is on, the DSM is getting power. I like the idea of being able to shut it off should the need arise. But I will admit to scratching my head when I first got the boat and was getting error messages on the MFD related to not finding the fishfinder.

 

[DennisG01]

Dennis - you may be right that the DSM only comes on once the MFD tells it to. However, the DSM has it's own power cable so whether or not the MFD is on, the DSM is getting power. I like the idea of being able to shut it off should the need arise. But I will admit to scratching my head when I first got the boat and was getting error messages on the MFD related to not finding the fishfinder.

That right there is all that matters.