Double clutch issue

[dmilton]

OHi,

I have an motorboat at 37ft and about 12 t,

The steering is hydraulic but the old autopilot was linear drive (autohelm 5000). 

Issue is that I have to activate the clutch on both the autohelm and the hydraulic pump when when activating the pilot / motor controller. 

So if linear drive tries to push/pull the rudder and the hydraulic pump is not deactivated the autohelm will automatically “de-clutch” so the rod will run freely. 

Is there a way to configure the time from activating the clutch to the time the controller tries to push/pull the linear drive. ?

Another thing I noticed the hydraulic clutch draws about 6amps while activated, isn’t that a bit high ?

Best regards
Dennis.

[seandepagnier]

Another case of something strange required.

yes, 6 amps is very high for the clutch. The latest hardware/software supports clutch pwm so after 300 milliseconds, the clutch output power can be greatly reduced (adjusted from 0-100%) to save power since it usually takes a lot less current to hold the clutch once it is engaged.

Are you saying you have a hydraulic pump for manual control (wheel?) and linear drive for pilot? How does the automatic de-clutch happen?

There is no way to configure the time currently, but it would not be impossible to add with a small software change. Often when activating the pilot no correction is immediately made. The clutch output applies power when engaged. Do you want to do the opposite for the hydraulic? It seems you may need a relay since the clutch output is really only made for 2-3 amps.

More details needed, I do not really understand your setup.

[dmilton]

Another case of something strange required.

yes, 6 amps is very high for the clutch.   The latest hardware/software supports clutch pwm so after 300 milliseconds, the clutch output power can be greatly reduced (adjusted from 0-100%) to save power since it usually takes a lot less current to hold the clutch once it is engaged.

Are you saying you have a hydraulic pump for manual control (wheel?) and linear drive for pilot?   How does the automatic de-clutch happen?

There is no way to configure the time currently, but it would not be impossible to add with a small software change.  Often when activating the pilot no correction is immediately made.   The clutch output applies power when engaged.  Do you want to do the opposite for the hydraulic?   It seems you may need a relay since the clutch output is really only  made for 2-3 amps.

More details needed, I do not really understand your setup.

my current setup is that, I have connected "both" clutch to the clutch output of the controller... my hydraulic is "manual" or "analog", if that make sense the only "power" i have connected to it, is to the clutch of the pump,
For the tiller to turn the rudder - it need to clutch the pump so it can run freely.

Do this make sense

[seandepagnier]

so applying power to the clutch of the pump bypasses it? So it takes power, and then allows the linear actuator to override?

I am unsure about the time delay needed. Do you mean it will trigger over current event because the hydraulic clutch takes time?

Well.. This is an interesting arrangement you have. A lot of hydraulic systems have bypass valves to allow an electric pump to move the rudder without back driving the wheel, but they are using hydraulic for the autopilot as well.

Still other arrangements use an electric motor to drive the steering wheel which then uses hydraulic to drive the rudder.

Other systems have a manual bypass valve on the hydraulic.

I have not heard of a system such as yours, but I am learning.

Would it be possible to manually bypass the hydraulic with a switch before engaging the pilot?

Could you use a time-delay circuit from the clutch output to the linear drive so it does not engage right away?

I am not suggesting either of these are best, but trying to fully understand what you are working with. Yes, pypilot could be modified to delay corrections after engaging.

[esm]

so applying power to the clutch of the pump bypasses it?   So it takes power, and then allows the linear actuator to override?

I am unsure about the time delay needed.  Do you mean it will trigger over current event because the hydraulic clutch takes time?

Well.. This is an interesting arrangement you have.   A lot of hydraulic systems have bypass valves to allow an electric pump to move the rudder without back driving the wheel, but they are using hydraulic for the autopilot as well.

Still other arrangements use an electric motor to drive the steering wheel which then uses hydraulic to drive the rudder.

Other systems have a manual bypass valve on the hydraulic.

I have not heard of a system such as yours, but I am learning.

Would it be possible to manually bypass the hydraulic with a switch before engaging the pilot?

Could you use a time-delay circuit from the clutch output to the linear drive so it does not engage right away?

I am not suggesting either of these are best, but trying to fully understand what you are working with.   Yes, pypilot could be modified to delay corrections after engaging.

Hi Sean, I am interested in this as well.  My boat currently has cable at the helm and hydraulic at the pilothouse.  The setup had a manual high-pressure ball valve under the sole in the aft cabin that you would have to switch on and off, with a wheel drive autopilot.  I went back in and tried a 12v ball valve and hard-wired switches in the cockpit and helm in the pilothouse, but have since moved on to a spool-valve.  I bought the hydraulic (high-voltage) controller and plumbed in an electric pump, and the setup worked nicely with the ball valve, with no current draw once actuated, but would leak due to the pressure.  The new spool valve is rated to 3000psi so you don't have the pressure problems but it does pull 2A of current, this problem can be fixed with the clutch and PWM settings.  My ask is there a way to engage the clutch, and control the spool valve, before you turn on the power to the pump engaging the autopilot in the software, to treat this like a bypass valve, without having other manual switches?  The reasoning for this is to be able to override the hydraulic steering if necessary to steer from the inside, to utilize the wheel pilot as a backup if should the hydraulic pump fail, and also to eliminate the need for adding an additional PWM from the switches to the valve.

[seandepagnier]

The autopilot always engages the clutch before manual movement command or when engaged. When in standby the clutch is released after any manual command. The pump is normally powered from the motor drive wires which reverse with direction and only powered during movement.

So to override this, it really depends on your setup, but you would either have to disengage the autopilot, or you could add an emergency switch to override the clutch and break this circuit. I am not really sure I understand exactly what is needed or if it is not already possible.