Lowrance wiring question

[bigeyes75]

I currently have an LCX27 and an LMS522 with a LGC3000 antenna on my boat. I have a transducer in the back and one on the trolling motor.

It appears that there is two NEMA red/black connections under the drivers side.

My question is this: I am purchasing a Lowrance HDS10 and an HDS7 both gen 1.

Will I be able to just replace the head units and everything will work or do I need to add NEMA connections or anything else?

I have no clue if I need to purchase additional items. I read something about having to add a Power node to get both HDS units to work.

Any help would be greatly appreciated.

[CaptainMusky]

Hey Bigeyes. You should be able to use the power cord to the new units without issue. My guess is the NMEA 2000 cables were installed to use the LGC3000 puck among all of the units. The HDS units have a great internal GPS so you have no need to even use the NMEA connections if you just used the internal GPS of each unit. If you have the structurescan LSS-1 or 2, then you would need to connect these units to the LSS module. It didn't sound like you had that so you could forget that piece. However, I would recommend getting the Lowrance Ethernet cable to connect between the two HDS units. This way you can share sonar and waypoints between them. Waypoints instantly will show up on both units. You save a waypoint on one BAM, its on the second unit and you don't even have to do anything. Very nice.

I think you should be fine to use the power and sonar cables that are already there for you. I had cables run for a 332 Lowrance, then upgraded to an HDS and the same cables worked fine for me.

[bigeyes75]

Thanks Captain Musky. You answered my question. I do not have the LSS 1 or 2. I knew about the Ethernet cable and was planning on buying it. You are correct. The previous units were linked to the 3000 with the NEMA. So, it sounds like I should be fine.

Thanks again. I am picking up my unit tonight and will test it out.

[bigeyes75]

Well I got the 10 in and it does not work with my external GPS puck. I have the 3000 puck on there.

Not sure if the gen 1 HDS10 is compatible or if I need to add a power nod or more NEMA connections.

The internal GPS and sonar are working. I plug in the Small black cord and it screws up my unit.

Any suggestions or help would be greatly appreciated.

[CaptainMusky]

The NMEA network requires a power node. You can either power it by tapping into the power plug that goes to the GPS unit or have its own separate power connection. Make sure the terminating connectors are installed as well. This was working before correct? Seems a bit odd to cause issues with the new unit as long as nothing else changed.

[bigeyes75]

It was working with my LCX27 and LMs522.

I called Lowrance and they said that the 3000 external antenna is compatible.

So either something is screwed up with my NEMA 2000 backbone or my antenna is bad.

[CaptainMusky]

You know how to change the GPS source correct? Once you hook up the NMEA cable and want to use the 3000 Puck, you need to change that in settings. I mentioned it "screws up your unit". what exactly does it do? Lock up?

Make sure the power node for the NMEA is hooked up.

[bigeyes75]

The unit freezes up. Also, the unit went to a white screen with black lines all over it.

I have tried to change from internal GPS to External GPS. How the heck do you do that? I cannot find it on my unit

[CaptainMusky]

I found this online. It might be a good idea to go to Lowrance's HSOforum and download the user manual if you do not have one. There is lots of helpful information in there...

Press the "Menu" button 2 times 4. Arrow down to "Network" and press the right arrow 5. Arrow down to "Data Sources" and press Enter 6. From the "Data Source Selection" Screen, highlight "GPS" and press the right arrow 7. Arrow down to "All Data (Global)" and press the right arrow 8. It should show a Blue Circle around "Auto" 9. Highlight the option you wish to use and press "Enter". Press the "Exit" button when finished. The 3 most common options are listed below: ? Auto - Automaticly switches between the external and internal GPS antennas based on which one has the best signal ? HDS-10 IGPS - Use this option if you want to only use the Internal GPS on the unit(this could be any HDS Unit, I am using an HDS 10 for my example) ? LGC-4000 - Use this option if you want to use only the External GPS Antenna

[CaptainMusky]

Aside from the issues you are having, I personally wouldn't even use that LGC3000. That is old and not even as accurate as the internal GPS is in your new HDS units.

I realize this may pose a rigging situation where you have an HDS mounted at a console and the puck is near the transducer, but the LGC 3000 has a high Feet of Error so there is little benefit in mounting them close to one another.

[bigeyes75]

Makes sense. The internal seems to work better anyways. Thanks for the info guys.