Which to buy 711c or 300?

Helmsman

Member
New install on a 31,000 lb Helmsman 38E Trawler with a single engine, and two helms. The boat is full NMEA 2000. Would like to use the SafeHelm2. I haven't been able to successfully distinguish the difference between the two AP's. Any suggestion as to which is the "best" for that type of boat?
 
The NAVPilot 300 series is designed mostly for center consoles and outboard engines. The 300 pilot is more restricted on the current it can give to a pump. Larger pump systems, solenoid systems, clutch drives, or wind mode requirements you must move to the 700 series. Your boat sounds like the NAVpilot 711c to me. What is the pump system you are driving?
 
Johnny Electron":8ammfdo6 said:
The NAVPilot 300 series is designed mostly for center consoles and outboard engines. The 300 pilot is more restricted on the current it can give to a pump. Larger pump systems, solenoid systems, clutch drives, or wind mode requirements you must move to the 700 series. Your boat sounds like the NAVpilot 711c to me. What is the pump system you are driving?

It has a Seastar Inboard BA175-7TM Hydraulic Marine Steering Cylinder which is 13.7 cu inches. The pump will be a PUMPHRP17-12.
 
PUMPHRP17-12 is a tough drive for the NAVpilot 300 and with a larger boat I would recommend the NAVPilot 711C for your boat. While you might be able to have the 300 work, you need to purchase a heading source and RRU to make it work when the Navpilot 711C comes with the needed RRU and PG700.
 
Johnny Electron":3usgs45x said:
PUMPHRP17-12 is a tough drive for the NAVpilot 300 and with a larger boat I would recommend the NAVPilot 711C for your boat. While you might be able to have the 300 work, you need to purchase a heading source and RRU to make it work when the Navpilot 711C comes with the needed RRU and PG700.

Ok. That is what I will go with. I plan to use an SCX20 in place of the heading sensor.
 
You might talk to the dealer and see if they will discount the purchase and remove the PG700 that is included, because you won't need that having the SC20.

If not; then you might go ahead and get the NP300 with the FAP6112 RRU and the SC20. I would also cut install cost by going with PUMPOCT16-12 to drive your cyl. This will drop your pump current requirements to a more comfortable level while cutting the pump cost in about half. The gain will be having the remote that comes with the NP300 and lower overall costs for the planned install.
 
Thanks Johnny. I want to be able to use Safe Helm. Can I do that with all of the suggested alternatives in your posts above?
 
Yes, but you need the SAFEHELM2 sensor installed to have that feature so you would want to add that sensor to your shopping list.
 
Johnny,

Here is a little more information.

The steering pumps (2 helms) are Teleflex Seastar model TFX HH5262-3 with a Seastar Inboard BA175-7TM Hydraulic Marine Steering Cylinder (which is listed as 13.7 cu inches). I an interested in the SAFEHELM2. The boat is a Helmsman Trawler 38e. The weight is 31,000 lbs.

I am sorry I am getting you this info in bits and pieces, and would appreciate you affirming which AP Control unit, processing unit, RRU, and pump would be the best fit with this additional information. I really appreciate you taking the time to help me sort this out and will order it upon your reply. Thank you.
 
If you want the wireless control the Navpilot 300 would work fine including SAFE HELM features as long as you get an RRU, SAFE HELM2, PUMP and Heading sensor. The 700 has no wireless option. The Navpilot 300 is all NMEA 2000 while the 700 is designed to support larger pumps, 0183 NMEA in addition to the 2000 and many other types of steering systems. I have no concerns about you running either model pilot but if going with the 300, I would opt for the octopus for two reasons. 1) cost 2) amperage efficiency.
 
Johnny,

I have purchased the 300 with the Octopus 16-12 pump. What size breaker should I use for the AP system? Also, do I need a fuse between the AP processor and the 16-12? If so, what size for that? I couldn’t find anything on the recommended breaker size in the manuals. If it is in there and I am just missing it, point in the right direction and I will look it up. Thank you.
 
You won't need to fuse the pump because pump power comes from the pilot and the pilot will be already protected. I would recommend you breaker the pilot for 15 Amps just to cover any turn on current.
 
Thanks Johnny, the maximum current draw of the Oct 16-12 is 17 amps per the manufacturer. Is the 15 amp fuse still adequate in light of that comment from them? I guess what I am asking is whether there would ever be a time that the current draw from the pump would exceed 15 amps and go to the 17 amp max draw?

Is there anything that states the max amp draw the processor will “allow” the pump? My understanding is normal operation is 5 to 7 amps. The max is what I need to size the breaker for.
 
The nominal current is 5 amps and I think going through the pilot it won't ever get to 17 amps even on surge, even if they list it as such. My document didn't list the peak of that pump but even if 17 is accurate, the pilot processor is going to modulate the power to the pump and I don't think you would ever see a 15 amp breaker pop using that pump. You can go to 17 if you want. We used to fuse the Navpilot 500 units on 30amp breakers due to turn on current but the 700 and 300 have large inductor coils to slow down the initial surges.
 
Johnny Electron":2rxnqoll said:
The nominal current is 5 amps and I think going through the pilot it won't ever get to 17 amps even on surge, even if they list it as such. My document didn't list the peak of that pump but even if 17 is accurate, the pilot processor is going to modulate the power to the pump and I don't think you would ever see a 15 amp breaker pop using that pump. You can go to 17 if you want. We used to fuse the Navpilot 500 units on 30amp breakers due to turn on current but the 700 and 300 have large inductor coils to slow down the initial surges.

Thank you Johnny. I will fuse at 15 amps and size the wire for 17 just in case. Have a great weekend!
 
Wire size is a diffrent thing entirely because you don't want fires or heat. Required gauge will depend greatly length of wire not just the possible draw of the unit.
 
Johnny Electron":1zlcs6v0 said:
Wire size is a diffrent thing entirely because you don't want fires or heat. Required gauge will depend greatly length of wire not just the possible draw of the unit.

Johnny,

From the breaker panel (using the suggested 15 amp breaker) to the processor the distance is roughly 10 feet (20 feet round trip). From the processor to the pump is 12 feet (24 feet round trip). The total distance for the circuit is therefore 44 feet round trip. The Blue Seas circuit wizard calls for 6 awg cable at 15amps. The determining factor is the total length of the run and keeping the voltage drop to less than 3%.

However, the Navpilot 300 install manual (Section 2.1.1) calls for 10AWG up to 15 meters (49 feet). The instructions do not differentiate for different size pumps. The only conclusion that can be drawn from that is that the processor would never allow more than 7 amps to the motor since the Blue Seas chart dictates that at 8 amps the AWG should change to 8AWG.

I am now thinking that moving to 8 AWG would provide the necessary margin of safety for the 15m specified in the manual.

Is there someone at Furuno that can confirm that the Navpilot 300 with an Octopump 16-12 protected with the suggested 15 amp fuse and a 15 meter round trip run would be acceptable with either 8AWG, or (per the installation manual guidelines) 10AWG? Or, perhaps that with a 15 amp fuse, the AWG6 should be used and perhaps the manual changed to reflect that?

Thanks for any advice that can be offered!
 
The cable feeding the processor should be 12 AWG minimum (or larger) in the case of running 12v. The pump wiring would require the same AWG based on what your cable lengths are. If you have 12 AWG or better; it sounds like you are good to go.
 
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