Mystery Relay

[nigel1]

Engine VP TMD22, on a Beneteau 473


In trying to sort out alternator issue, I investigated a relay which is cable tied near to the starter motor, and I have a no idea what its is for, or even if it does anything.

Its not shown on the Volvo Penta electrical drawings, so it could have been fitted by Beneteau (it’s a French relay)

Relay is made by G. Cartier, 12V 25A, with type number 03.601.

Four spade terminals, 1,2, 3 and 5

Terminal 1 – Red wire connected to D+ on alternator

Terminal 2- Back Wire connected to B- on alternator. Terminal 2 is also bridged to Terminal 5

Terminal 3 – Black wire which disappears down towards the bilge.

Following this black wire it then runs parallel to a red wire, which has been cut, so it looks like at some point, this red wire might have been connected to the relay. The red and black wires have been taped together, but at the moment, I cannot trace the full length so no idea where it goes to.

Anyone have an idea what it might have been used for.

The way the relay is wired at the moment, it would appear to have no purpose.

 

[Refueler]

Was there any additional unit on the boat before such as a portable fridge / coolbox or other item needing power ? I have similar on one of my boats - when engine starts and alternator kicks in ... the relay closes and powers my Coolbox. Engine stops - relay opens and power cuts off to the box.
fitted to protect batterys from being drained when engine not running.

Just an idea ...

 

[Alex_Blackwood]

Engine VP TMD22, on a Beneteau 473


In trying to sort out alternator issue, I investigated a relay which is cable tied near to the starter motor, and I have a no idea what its is for, or even if it does anything.

Its not shown on the Volvo Penta electrical drawings, so it could have been fitted by Beneteau (it’s a French relay)

Relay is made by G. Cartier, 12V 25A, with type number 03.601.

Four spade terminals, 1,2, 3 and 5

Terminal 1 – Red wire connected to D+ on alternator

Terminal 2- Back Wire connected to B- on alternator. Terminal 2 is also bridged to Terminal 5

Terminal 3 – Black wire which disappears down towards the bilge.

Following this black wire it then runs parallel to a red wire, which has been cut, so it looks like at some point, this red wire might have been connected to the relay. The red and black wires have been taped together, but at the moment, I cannot trace the full length so no idea where it goes to.

Anyone have an idea what it might have been used for.

The way the relay is wired at the moment, it would appear to have no purpose.

looks like it was meant to "Make" when engine running and de-energise when engine stopped. Other than that. Who knows? If terminal 2 and 5 bridged then suspect it was switching -ve and what ever it was switching was getting +ve feed from somewhere else?
Of course I could be completely wrong

 

[AngusMcDoon]

Some boats are wired so that a bow thruster or windlass can only be operated when the engine is running. This relay might energise the relay that powers either of these 2 items. This is a much more common scenario than a fridge being depowered when the engine is not running.

 

[PaulRainbow]

looks like it was meant to "Make" when engine running and de-energise when engine stopped.

Yes, that's what it's doing

Other than that. Who knows? If terminal 2 and 5 bridged then suspect it was switching -ve and what ever it was switching was getting +ve feed from somewhere else?
Of course I could be completely wrong

 

[PaulRainbow]

Some boats are wired so that a bow thruster or windlass can only be operated when the engine is running. This relay might energise the relay that powers either of these 2 items. This is a much more common scenario than a fridge being depowered when the engine is not running.

That was my first thought to, Beneteau/Jeaneau did indeed fit a relay on later boats. But, the ones i have seen look like this :

 

[ithet]

This query regularly turns up for Beneteaus. It is a relay for only operating the windlass with motor running and they are often disconnected on owner boats (like mine) rather than charter boats. Confusion arises as they are fitted in the low power circuit to the contractor box and separate to main power relay/breaker for the windlass.

 

[ithet]

This query regularly turns up for Beneteaus. It is a relay for only operating the windlass with motor running and they are often disconnected on owner boats (like mine) rather than charter boats. Confusion arises as they are fitted in the low power circuit to the contractor box and separate to main power relay/breaker for the windlass.

And on my particular yacht the original wiring harness has both a positive and negative adjacent to the disconnected relay which I presume was to allow for either to be switched depending on the actual windlass that was factory fitted.

 

[Alex_Blackwood]

Yes, that's what it's doing

Without a wire on terminal 5 it can't do anything. I'd be inclined to take the relay and wiring out.

When energised relay contact makes it links 3-5 and 5 briged to 2(-ve) so switching negative, no?

 

[PaulRainbow]

When energised relay contact makes it links 3-5 and 5 briged to 2(-ve) so switching negative, no?

Sorry, missed that 2 and 5 are linked, so yes, it's switching negative.

Post #5 edited accordingly.

 

[Alex_Blackwood]

Sorry, missed that 2 and 5 are linked, so yes, it's switching negative.

Post #5 edited accordingly.

We have all done it Paul, some of us more times than we would like to admit
Could trhere be a +ve live lurking somewhere? I would be inclined to do a bit of serious tracing, just in case, you never know

 

[Refueler]

Some boats are wired so that a bow thruster or windlass can only be operated when the engine is running. This relay might energise the relay that powers either of these 2 items. This is a much more common scenario than a fridge being depowered when the engine is not running.

Do not ignore that the rel;ay is 25A max .... so I do not think it was for serious high power gear ....

Given that my Coolbox drags about 8A average and 10A initial ... then having a relay is a sensible idea ....

 

[nigel1]

Thanks for the replies.
I had worked out that the relay was configured to complete a circuit on the negative side>
Crossed my mind regarding the windlass, I think it was pretty much standard that Beneteau wired the windlass circuit so that it could only be operated with the egine running, and equally aware that many owners bypassed it.
I initially discounted this based on the low amperage rating of the relay, but if as ithet said, it makes sense if this was on the lower power side of of the windlass solenoid.

Cheers
Nigel

 

[Plum]

Thanks for the replies.
I had worked out that the relay was configured to complete a circuit on the negative side>
Crossed my mind regarding the windlass, I think it was pretty much standard that Beneteau wired the windlass circuit so that it could only be operated with the egine running, and equally aware that many owners bypassed it.
I initially discounted this based on the low amperage rating of the relay, but if as ithet said, it makes sense if this was on the lower power side of of the windlass solenoid.

Cheers
Nigel

As others have said, the relay was fitted by Beneteau to ensure the engine is running before the windlass can opperate. Same as on my Beneteau but long since disconnected.

 

[nigel1]

As others have said, the relay was fitted by Beneteau to ensure the engine is running before the windlass can opperate. Same as on my Beneteau but long since disconnected.

Thanks, that picture clears up the mystery.
I'll remove it to avoid any future confusion.

Thanks
Nigel

 

[PaulRainbow]

Do not ignore that the rel;ay is 25A max .... so I do not think it was for serious high power gear ....

Given that my Coolbox drags about 8A average and 10A initial ... then having a relay is a sensible idea ....

When relays are fitted to stop you using the bow thruster or windlass the usual method is for the rely to power the switching circuit, not the main loads.

 

[AngusMcDoon]

Do not ignore that the rel;ay is 25A max .... so I do not think it was for serious high power gear ....

I didn't.

 

[Refueler]

When relays are fitted to stop you using the bow thruster or windlass the usual method is for the rely to power the switching circuit, not the main loads.

I realised that after posting - but the comment still stands though generally.