Autopilot disconnect switch

[NorthernMac]

Hey guys,

I'm going to be adding a cockpit autopilot disconnect switch.

System is
Open CPN/pi 4+/HAT2 on a German made break out board to NEMA and 12vdc

Autopilot controller is a new pipilot

Autopilot is a raymarine type 1



With a switch like this



https://m.dhgate.com/discount/waterp...h-on-sale.html

So the idea is if things went pear shaped, I could hit the button and 100% deactivate the AP

Would I just interrupt the negative of the clutch wire?


Thanks

[Wotname]

I can't see the switch from the link.

I would check the current draw of the clutch and the specs of the switch to see if the switch can carry the current.

Then I would confirm if the switch has a momentary action or not. Whatever the action is, you can try it first by manually doing the same action with the clutch wiring.

[slug]

Originally Posted by NorthernMac

Hey guys,

I'm going to be adding a cockpit autopilot disconnect switch.

System is
Open CPN/pi 4+/HAT2 on a German made break out board to NEMA and 12vdc

Autopilot controller is a new pipilot

Autopilot is a raymarine type 1



With a switch like this



https://m.dhgate.com/discount/waterp...h-on-sale.html

So the idea is if things went pear shaped, I could hit the button and 100% deactivate the AP

Would I just interrupt the negative of the clutch wire?


Thanks

Don’t know your autopilot


On my pilot the kill switch .... named STANDBY....
Breaks the clutch and motor power supply via a MOSFET relay

If your only broke clutch , the motor would continue to Run until it smoked out

Be alert

[NorthernMac]

Originally Posted by slug

Don’t know your autopilot


On my pilot the kill switch .... named STANDBY....
Breaks the clutch and motor power supply via a MOSFET relay

If your only broke clutch , the motor would continue to Run until it smoked out

Be alert

So what would be the best way to execute this?

Ideally I'd like it to be pumpkin spice basic, less relays and whatnot the better

[Wotname]

Originally Posted by NorthernMac

So what would be the best way to execute this?

Ideally I'd like it to be pumpkin spice basic, less relays and whatnot the better

Any switch (or switches) at the helm isn't going to tough enough to handle the normal motor current unless the are big multipole switches. The wiring run would likely to excessive as well. Which is why we use relays etc.

Doesn't the AP already have a disconnect function???????

[NorthernMac]

Originally Posted by Wotname

Any switch (or switches) at the helm isn't going to tough enough to handle the normal motor current unless the are big multipole switches. The wiring run would likely to excessive as well. Which is why we use relays etc.

Doesn't the AP already have a disconnect function???????

It does, but software based, I need a hardware disconnect redundancy

[jamhass]

Our Ray course computer (CC) has a disable/standby circuit. (Sorry, sold the boat, have to look hard to find exact info).

I installed a safety switch to disable the CC when the Ram was physically disconnected from the tiller (long story).

If I used the disable/standby circuit of the Ray CC, energizing this switch caused the CC to reboot, taking a long time to come back online.

At least for my purpose (disable the Ram rather than the CC) I relayed the power supply to the Ram, and left the CC running.

Much better overall.

[Wotname]

Originally Posted by NorthernMac

It does, but software based, I need a hardware disconnect redundancy

OK, I get that

I had a look at the installation manual and although it doesn't give a much fine detail, it states the AP drive unit uses 36 watts at 12V. I am guessing most of this is by the motor rather than the clutch.

It should be straightforward to interrupt one leg of the clutch circuit and one leg of the motor circuit with 2 pole switch. I would chose a 2 pole switch that is good for at least 5 amps but more if possible (say >8 amps). One pole of the switch should interrupt the clutch circuit and the other pole should interrupt the motor circuit. It does't matter which side of each circuit you interrupt.

The install manual gives you the necessary wire sizes depending on length of run.

You would find a suitable Eaton switch here https://www.eaton.com/Eaton/Products...gles/index.htm

You could fit a missile switch cover guard if you felt it was necessary https://www.sparkfun.com/products/9278

I have on idea what the autopilot controller will do when it realises the drive unit is not responding to it's commands but that isn't part of your question. The drive will be safe though!

[NorthernMac]

Originally Posted by Wotname

OK, I get that

I had a look at the installation manual and although it doesn't give a much fine detail, it states the AP drive unit uses 36 watts at 12V. I am guessing most of this is by the motor rather than the clutch.

It should be straightforward to interrupt one leg of the clutch circuit and one leg of the motor circuit with 2 pole switch. I would chose a 2 pole switch that is good for at least 5 amps but more if possible (say >8 amps). One pole of the switch should interrupt the clutch circuit and the other pole should interrupt the motor circuit. It does't matter which side of each circuit you interrupt.

The install manual gives you the necessary wire sizes depending on length of run.

You would find a suitable Eaton switch here https://www.eaton.com/Eaton/Products...gles/index.htm

You could fit a missile switch cover guard if you felt it was necessary https://www.sparkfun.com/products/9278

I have on idea what the autopilot controller will do when it realises the drive unit is not responding to it's commands but that isn't part of your question. The drive will be safe though!

What do you think the pypilot AP controller will do?

[Wotname]

Originally Posted by NorthernMac

What do you think the pypilot AP controller will do?

Opps... There was a typo in my previous reply. It should have read "I have no idea what the autopilot controller will do when it realises the drive unit is not responding to it's commands...".

It might do nothing or it might alarm or it might shut down but probably whatever happens, it won't break it.