Cockpit Pilot SPX-5 and Hydraulic Pump Possible ?

[olaf hart]

I'm OK with no clutch output from the SX-5, I isolated the clutch wiring in the linear drive and plan to put the switch on the steering pedestal. With a rudder position indicator I could set the autopilot and switch the drive in and out when I want it.

Like the MOSFET Idea, I built a relay setup a while ago, but it used four relays IIRC. Does anyone have a link to a suitable circuit diagram, or should I just duplicate the relay setup using Mosfets?
Do they have any specific requirements such as 5v switching, or will the SX-5 output drive the switched direct?

[Cap Erict3]

Originally Posted by evm1024

Well let's just dig this thread ouut....



The SPX-5 uses the same mosfets that the spx-10 does. This implies that the H-bridge on the spx-5 has the same potential drive capabilities as the spx-10. Differences are the installed fuse, the PCB trace size and heatsink size.

Another difference is that the spx-10 has a solenoid output that enables the pump oil circuit.

Looking at the schematics of the spx-5 and spx-10 I see that they have the same pinouts in the CPU with the exception that the spc-5 pulls up the outputs for the solenoid drive and solenoid over current (and other unused functions I'm sure).

The question is: Does the spx-5 software send a solenoid signal when in auto? When I get time I'll have to measure this.

I am curious to find out if one could drive a pump. Even if you had to manually activate the solenoid.

Any others have insight to this?

Regards

I have sailed about 700 miles since converting to the hydraulic pump. No problems as yet.

With the relays installed, the minor corrections that the computer is sending do not happen until the output reaches coil closing minimum so it likely over steers a bit.

Would you provide a link to the SPX-5 schematics you refer to?

[Cap Erict3]

Adjusted pump output down about a month ago. Today checked motor current and found 4-6 amps.

Bypassed relays and connected directly to SPX-5. Output transistors are plenty big. My primary concern is heat dissipation.

Dockside tests worked ok. I'll have to an area big enough to maneuver before recalibration of course computer.

[roland stockham]

As mentioned earlier I have opted for this H bridge Robot MarketPlace - Simple-H HV H-Bridge. after the replies I go here.

Thought it might help some of you to say why. Main thing is that the pump I have CAN draw 18a. I very rarely WILL, but it can. That is likely if running hard downwind in a following sea. If the boat starts to surf she tends to curve slowly into a broach and I have seen 15kn on the clock (this was in 15-20ft waves with 30kn over the deck and two much sail up!!). She came back on course but it took two hands on the wheel and a good pull. The auto pilot is going to stall out under these conditions and draw it's max current. With it hooked up to the XP5 direct it will burn out the outputs. I am setting up the boat for the Panama Hawaii leg, 6000+ miles of trade wind sailing so this is likely. Coastal sailing it may not matter.
The other reason is that using the comercial H bridge it is set up as an amplifier not just an On-Off switch. Out put is PWM controlled to mirror input so I am hoping it will give a smoother drive.
Will let you all now the result but not till July!

[evm1024]

One 'easy' option is to double up one the fets used in the spx-5 h-bridge. The schematic is around. One could pull the onboard fets and pull the control lines out of the box to an outboard h-bridge with a nice heatsink.

The spx 30 schematic is around too. That h-bridge could be built the same way.....

Regards!

[ghaffy]

Reinforcing the power of the course computer by any means sounds to be a pretty reasonable idea, especially when one is expecting remarkebly higher loads, I guess.
Just to add a little bit to the history of our conversion: we did some 2,000 nm since I exchanged the helmdrive by the hyraulic pump (2 ys. ago, without any further modifications), some of the miles under comparatively heavy conditions. No problems so far.

But our "baby trawler" is small (25 ft), motor powered (no sails), and navigating through relatively fair seas (Adriatic). Anyhow, meanwhile we have "forgotten" that the setup once was different, which seems to be a comforting experience.

[evm1024]

That's very nice to know. I'd forgotten (and did not look on page 1) that I had written something in this thread.

Regards

[wgoodbye]

Hi Roland

I'm looking at a similar project to convert my X5 wheel pilot on a Seaward 32RK to control an under-deck hydraulic actuator. The HV bridge you mentioned on robot marketplace looks simple and economical. Thanks for that. Do you happen to have a wiring diagram on how all of this would connect together from the AP to the actuator?

Thanks in advance

Chris

Originally Posted by roland stockham

As mentioned earlier I have opted for this H bridge Robot MarketPlace - Simple-H HV H-Bridge. after the replies I go here.

Thought it might help some of you to say why. Main thing is that the pump I have CAN draw 18a. I very rarely WILL, but it can. That is likely if running hard downwind in a following sea. If the boat starts to surf she tends to curve slowly into a broach and I have seen 15kn on the clock (this was in 15-20ft waves with 30kn over the deck and two much sail up!!). She came back on course but it took two hands on the wheel and a good pull. The auto pilot is going to stall out under these conditions and draw it's max current. With it hooked up to the XP5 direct it will burn out the outputs. I am setting up the boat for the Panama Hawaii leg, 6000+ miles of trade wind sailing so this is likely. Coastal sailing it may not matter.
The other reason is that using the comercial H bridge it is set up as an amplifier not just an On-Off switch. Out put is PWM controlled to mirror input so I am hoping it will give a smoother drive.
Will let you all now the result but not till July!

[roland stockham]

I am hoping that, because this is an amplifier not just a relay, I can simply hook up the A/P output to the H bridge inputs. The H bridge should then mirror anything it receives but with higher potential amps behind it. Not sure if the output from the X-5 is clever or just on/off so this might not be needed but also gives a better upgrade path if I change pilot controllers in the future. The output power seems to be the bit that puts the price up on all of them. I will be fitting it in June and will post results but there was feedback on the robot site from someone who has do exactly the same and reported good results. Going to fit the H bridge in a water tight box but not sure where yet. Can be anywhere between the controller and the pump but should aim to keep the power line as short as possible all the way from the breaker to the pump, 20a can cause significant voltage drops

[Cap Erict3]

Originally Posted by roland stockham

I am hoping that, because this is an amplifier not just a relay, I can simply hook up the A/P output to the H bridge inputs. The H bridge should then mirror anything it receives but with higher potential amps behind it. Not sure if the output from the X-5 is clever or just on/off so this might not be needed but also gives a better upgrade path if I change pilot controllers in the future. The output power seems to be the bit that puts the price up on all of them. I will be fitting it in June and will post results but there was feedback on the robot site from someone who has do exactly the same and reported good results. Going to fit the H bridge in a water tight box but not sure where yet. Can be anywhere between the controller and the pump but should aim to keep the power line as short as possible all the way from the breaker to the pump, 20a can cause significant voltage drops

How did ur project work out?


------------------------------
Looking for another pretty place to work on the boat.

[bossuet77]

hello
how do you connect 1/4 pump port with 3/8 hose ?
thank you if you can answer.
est regards
claude

[Bill O]

Originally Posted by bossuet77

hello
how do you connect 1/4 pump port with 3/8 hose ?
thank you if you can answer.
est regards
claude

Use a reducer. Ck thread type, most likely pipe thread. Do you have a hydraulic hose/fitting store near you? They will have better fittings than a general hardware store or something like this if your hose end is fixed.

[bossuet77]

thank you very much
I will take your advice and bring the pump and fittings to a farm equipment dealer near me.
best regards

[Bill O]

What pump do you have? Have you looked online for a diagram that may tell you the tread size for the port?

Anyway, try to get the fitting w/a swivel (vs. a straight plumbing type reducer), it will make much easier to properly tighten the fittings.
Also purchase a liquid sealant for oil/diesel fittings (Loctite, Permatex, etc.) to use instead of teflon tape.

[bossuet77]

i am considering purchasing a hy-prodrive pump for an autopilot. (https://www.hypro.co.uk/products/hyd...versing-pumps/).
they provide adapters but i feel like they are adapters directly on the hose (https://www.hypro.co.uk/products/hyd...eversing-pumps / port-adaptors /).
At the level of the main pump, the connection is male G 3/8. (https://adriamarine.net/fr/timonerie...verticale.html)