navpilot 711-c with jefa dd1

[OliverFdeV]

Does anybody know it the combination of the navpilot 711-c with a Jefa DD1 direct drive would work?

On a dutch forum I found a mention of an earlier version navpilot working ok with the Jefa dd1.

On https://www.jefa.com/steering/products/ ... ct-dd1.htm it says that the combination of Jefa and furuno is not advisable due to lack of speed control and dynamic braking.

But the 711-c does have pulse width modulation and has the autotrim ability to keep the rudder in a certain position.

So does anyone have this combintion working?

Reason I ask is that the power consumption of the jefa dd1 seesm to be lots less than a hydraulic unit

 

[Johnny Electron]

Talking with our product development we don't believe that drive system will work properly with the NavPilot. For sailboats we have interfaced with many types like wittlock drives, clutch systems, Solenoid systems, linear actuators etc but this one is not one we have enough information on to be of assistance. Being the drive system company says it doesn't work, I would defer to them.

 

[OliverFdeV]

HI Johnny Electron,

Thanks for answering, interestingly I did just that: ask the makers of the jefa drive, here is the answer I just got:

Hi,
How the pilot steer the vessel is not important for our drive, as it is in fact a simple motor.

It is important that the clutch always have 12 volt when the pilot is engaged, and the pilot modulate the pover to the drive. ( increase and decrease the pover to the drive slowly)

Please contact Furono about this matter, and they give you the information that our drive works with their pilot.

Best regards.
Jefa

So it boils down to these two questions then:
1 - does the clutch always have 12 volt when the pilot is engaged?
2 - does the pilot modulate the power to the drive, i.e. increase and decrease the power to the drive slowly?

So if you could answer these 2 questions we have the answer.

Thanks!

 

[Taniwani]

I don't have the combination you are looking for, but I can tell you that the Jefa drives are not much different from the same Whitlock series. Main difference is that the Jefa drives consume less power for keeping the clutch engaged. All need 12V to be on as long as the pilot is engaged. Motor wise it is pretty similar. I think the advise on Jefa's website to not combine it with Furuno NavPilots appears unfunded, probably they never checked out that combination.

 

[OliverFdeV]

Thanks Taniwani, much appreciated.

So you are implying that the answer to the first question is yes, i.e. the navpilot 711c keeps the clutch engaged while the autopilot is powered on.

Because according to Jefa it boils down to these two questions:

1 - does the clutch always have 12 volt when the pilot is engaged?

If the answer to this question is yes, then the second question remains:

2 - does the pilot modulate the power to the drive, i.e. increase and decrease the power to the drive slowly?

Once I know the answer to both questions for sure I am good to go.

Thanks!

 

[Taniwani]

In short yes to both your questions.

Regarding 1: Power will be applied to the clutch as long as the autopilot is engaged. You may have a choice of 12V or 24V as the NavPilot can be used with both systems.

Regarding 2: All modern autopilots, including the NavPilots use PWM to control output power to the drive or pump motor varying power is needed and rarely go over 60% duty cycle. You can select if you drive motors or solenoid valves (actually I think the NavPilot figures out what you have connected) and for the later it is on/off only. The actual power output to motors depends on many factors, like rudder gain and feedback form the reference unit.

 

[OliverFdeV]

Taniwani, thank you very much.

This is what I needed to know.

Thanks again!

 

[Johnny Electron]

Let us know how it all turns out.