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hds7 ?
Posted: Fri Apr 06, 2012 12:53 pm
by kane-o
ken or marc, whats the difference between the 3 wire cord for my 28hd and the 2 wire cord for the hds 7 ? i hooked up the new hds7 w/ insight on the console where the 28 was. and just used all the existing power cord, sonar cord, and the nema cord and everything seems to be fine ! i get gps, and sonar, and my structure scan seems fine as well... do i really need to change the power cord from the 3 wire to the 2 wire ? and if so does the 2 wire get an inline fuse connected to it ?? thanks again for all the help guys !!
Re: hds7 ?
Posted: Fri Apr 06, 2012 3:36 pm
by Ken Sauret
The LCX units powered the NMEA network through the unit itself. This is why there was a three wire cable. The fat cable was power to the unit itself and the small cable labeled NMEA was the power to the NMEA network. Lowrance found that guys would connect the NMEA cables on the unit at the console and the unit at the bow. This "double powering" of the NMEA network would cause problems sometimes blowing out the GPS antenna.
The HDS power cable is a two wire cable because the NMEA network can no longer get power through the unit itself. Now the NMEA needs to be powered via a power node which is a tee in the NMEA network with a hot and a ground wire coming out of the top. When these are connected to a hot and ground then the external GPS antenna or other NMEA network devices will have power to operate.
I would take a few minutes and change out the three wire cable to the new two wire cable. If you don't want to do this at least go underneath and disconnect the NMEA cable in the three wire harness! Older wire cables will fatigue over time and you have a new power cable in your hands. Follow the old power cable to the power and ground sources and connect the new power cable. This may avoid power problems in the future.
All red/hot wires need to have their own individual fuses.
Re: hds7 ?
Posted: Sat Apr 07, 2012 6:48 am
by kane-o
ken, if i use the new 2 wire power cord, can i eliminate the nema all together and just use the internal gps antenna's ? thus getting rid of the 3 "t " connectors and the 2 nema cords from the bow and transom. using the lss-1 to link them together with 2 erthernet cords ? i will be keeping the 3000 gps puck just because i dont want a hole in my top cap... will this work ??

thanks ....
Re: hds7 ?
Posted: Sat Apr 07, 2012 4:38 pm
by NoCAL
If you are keeping the LGC-3000 you have to keep the NMEA network. I ended up getting rid of mine and filling the holes with Marine Tex. You can't hardly even tell it was there. So I basically have the network but I don't use it for anything. If I ever get an LGC-4000 the network is in place and ready to hook into.
NoCAL
Re: hds7 ?
Posted: Mon Apr 09, 2012 12:12 pm
by Ken Sauret
NoCal is right. If you use the internal GPS antennas on the HDS units, you perceivably don't need the NMEA network but I would leave it in place for later use if you upgrade to an LGC 4000.
The LSS-1 box will network the Structure Scan sonar image between both units but it won't allow you to share a broadband sonar transducer. I haven't disconnected my NMEA to see if both units will share waypoints via the LSS-1 box. Just experiment to find out if both will share waypoints after you disconnect the NMEA network.