Multifunction displays and cameras... does display turn on voltage to the cam, or ?

[Dune]

Situation is 2011 vintage Raymarine E120 W display. Have two analog video cams, Speco CNC-627M. When I go to video mode on the Raymarine one can choose 4 different cameras. I have 2 cameras, one in engine room, one aimed aft outside aft deck.

The one in engine room shows up fine on the display as camera 3. The other one...no signal. Yesterday found out "no signal" is because prior to my ownership of the boat someone pulled the cable out of the camera far enough that not only did it disconnect the wires from the connector internally, but as it pulled thru it caused the end terminals all 3 wires to end up touching each other !

So after separating the wires, I check voltage and get nothing...presume the touching caused a short somewhere.

The point of all this rambling is it would help to know how exactly these things are supposed to work to know where to look for a blown fuse or whatever. So the question is-

When you are in video mode on the Raymarine E120 and press, say, camera two....does the Raymarine turn on 12 volts to camera two....or do the cameras always have 12 volts "on" and the Raymarine only allows the signal wire activated for camera two ?

 

[Codger2]

When you are in video mode on the Raymarine E120 and press, say, camera two....does the Raymarine turn on 12 volts to camera two....or do the cameras always have 12 volts "on" and the Raymarine only allows the signal wire activated for camera two ?

My electronic guru says that the cameras always have power to them. I can't, however, confirm that! I also have two cameras, one that looks down on the cockpit and stern (handy for backing) & one in the ER. The cockpit camera is the most useful (IMO) as the ER camera doesn't give me much field of view.

 

[Dune]

My electronic guru says that the cameras always have power to them. I can't, however, confirm that!

It would make the most sense to me that the Raymarine display would not turn on the 12 volts but rather simply switches to the desired signal wire. But then again it seems a bit odd there would always be 12V on at the cameras even when not in use....so not sure what to think there.

However it is arranged, thank goodness the power wire short circuit in the aft camera didn't effect the entire video system.

 

[psneeld]

It would make the most sense to me that the Raymarine display would not turn on the 12 volts but rather simply switches to the desired signal wire. But then again it seems a bit odd there would always be 12V on at the cameras even when not in use....so not sure what to think there.

However it is arranged, thank goodness the power wire short circuit in the aft camera didn't effect the entire video system.

Why? I would think it typical that cameras are hotwired so you could view just by switching the video feed from them...as in surveillance cameras.

No need to wire some sort of switch at a remote camera location...especially if wireless.

 

[Dune]

Why? I would think it typical that cameras are hotwired so you could view just by switching the video feed from them...as in surveillance cameras.

No need to wire some sort of switch at a remote camera location...especially if wireless.

Typical for security systems indeed but seems a little over the top to have a camera with voltage on 24/7 when one might be away from the boat. Still, apparently the cameras are designed with that in mind so I guess it's ok. Regardless I found the problem on Saturday... 12V input was disconnected deep in the bowels (space between flybridge floor and salon ceiling) of the boat.... a simple plug that required pulling 25 feet of wire to find....no clue how that happened.