NAC-3 AP with linear feedback sensor?

[chowdan]

Hey all,

I am installing a navico NAC-3 autopilot and will use my Palegic system as a back up(to control emergency tiller arm and eventually hydrovane rudder).

I went ahead and purchased(reluctantly) the simrad RF25 rudder sensor because Simrad people told me the LF3000 was NOT compatible with the NAC3. When they said that I decided I'd purchase the RF25 which should be arriving this weekend and I figured i'd attempt to do a virtual rudder sensor to configure everything and make sure the system turns the wheel both directions.

Well I am getting "drive inhibit" when attempting to have the system turn to port, starboard turns totally fine. Discussing with B&G today said "you can totally use the LF3000 with the NAC3, all we care about is frequency, you just hook it up and it should work fine".

I told them the NAC-3 requires 2 wires, the LF3000 that i have is a 3 wire unit. His response was "just wire it up and it should work".....Anyone use this/have opinions on how to wire it? I believe wiring requires 5v if i'm not mistaken?

[s/v Jedi]

You checked the manual, right? shield to ground, two conductors to terminals

[chowdan]

Originally Posted by s/v Jedi

You checked the manual, right? shield to ground, two conductors to terminals

Yeah, shield to ground but the system I have is a 3 wire system. Third wire isn't a shield, unless they are now making shields look just like another wire?

I find it hard to believe that their NAC 2 system would actually work with my rudder sensor, but the NAC3 would require a totally different style rudder sensor.

Bright side i guess with the new rudder sensor thats on its way is that it's a NMEA2k one, but damn is it ridiculously expensive on top of the expensive piece i already have.

[s/v Jedi]

Originally Posted by chowdan

Yeah, shield to ground but the system I have is a 3 wire system. Third wire isn't a shield, unless they are now making shields look just like another wire?

I find it hard to believe that their NAC 2 system would actually work with my rudder sensor, but the NAC3 would require a totally different style rudder sensor.

Bright side i guess with the new rudder sensor thats on its way is that it's a NMEA2k one, but damn is it ridiculously expensive on top of the expensive piece i already have.

It works. I like the nmea2000 better because you get rudder position on the network independent from the AP

[chowdan]

Originally Posted by s/v Jedi

It works. I like the nmea2000 better because you get rudder position on the network independent from the AP

Yeah, i am more just frustrated that I have to spend another $400 for a rudder sensor when i already have one....I've already eaten the cost and the NAC3 i purchased was VERY cheap vs retail pricing($600), so i guess its not the end of the world.

Having rudder position on the network will be nice for someone like my wife who struggles with figuring out where the rudder is.

[s/v Jedi]

Originally Posted by chowdan

Yeah, i am more just frustrated that I have to spend another $400 for a rudder sensor when i already have one....I've already eaten the cost and the NAC3 i purchased was VERY cheap vs retail pricing($600), so i guess its not the end of the world.

Having rudder position on the network will be nice for someone like my wife who struggles with figuring out where the rudder is.

Oh wait… LF3000…. I have the RF300 which is completely different. I now agree that I don’t think your rudder feedback sensor works.

I sold my RF300 and bought the RF25 to get it as a nmea sensor. It’s great, you won’t be disappointed with it.

[PippaB]

NAC2 used a resistive rudder feedback signal, NAC3 uses frequency. LF3000 should work, with an LFI3000 Mk2 interface card. That powers and picks up the differential signal from the LF3000 and turns it into frequency.