Rocker Switches

[petem]

Fellow T34 owners will be familiar with the engine master switches that are placed below the helm seat bolster. They are connected to two relays and illuminate when the up switch is depressed. Well, that's what they are supposed to do but only one of mine illuminates.

Anyhow, the previous owner (-1) recently reminded me that the switches are very poorly placed as they are unguarded and can be accidentally switched off (they are immediately behind the skipper thigh). The symptom of this is that the impacted engine will start to hunt and the cause of this will not be apparent to the skipper. (I wonder if this might have been what caused the issue that one of my partners experienced in the summer that we attributed to fuel or slipping alternator belt.)

In light of the above (and because I like everything to be working on my boat) I have been investigating a fix.

I believe the switches are Carling V Series. You can find details here...

http://www.carlingtech.com/sites/default/files/documents/V-Series-IV-V-VII_datasheet.pdf

(JFM and other geeks will observe that they are Contura II actuators, unlike the dash that has Contura III actuators .)

V Series switches come in many different flavours and I believe a switch like this that drives a relay will be a (On)Off(On). The ( ) brackets mean momentary.

In addition, the switch needs to be illuminated (red). There are two different types of illumination; one type where the switch also illuminates the light, the other type where the switch is independently lit. I believe these switches have the latter. I think this is the exact model http://www.cactusnav.com/carling-series-contura-switch-only-back-light-p-15891.html.

So I'm wondering might be stopping my switch from illuminating. I suspect it could be one of the following...

1) Somebody has replaced the switch with the wrong type (unlit)
2) A loose connection at the switch end
3) A bulb failure
4) A loose connection at the relay end (I'm not sure where the relays are located)

So my question is, assuming the switch is independently illuminated, where does it get it's power from? Is it wired to the relay or the engine circuit (that is given power from the relay)?

This got me further thinking (dangerous I know). The two bilge pumps can be switched on by activating the float switches or the manual switches on the helm (both of which are illuminated). So I now wonder if the lights on the helm switches activate by the switch or whether they will illuminate independently (i.e. by activation of the float switch). Anyone know? If I had the wiring diagrams or access to the boat I'd be able to find out.

Pete

 

[Portofino]

I d start with getting them the right way round first .
Apologies if the pic is transposed

 

[petem]

I d start with getting them the right way round first .
Apologies if the pic is transposed

The camera is looking back at the switches so they are the correct way around.

 

[Portofino]

The camera is looking back at the switches so they are the correct way around.

Sorry P for appearing a bit thick on this but what do you mean ,i can,t see it “ cameras looking back —- “

Run it by me again ps

Does it have to be OEM ?
Thinking in bright daylight Med sun , Raybans on are you going to see any illumination?
So give up and fit something like this that hopefully won,t get taped / knocked off
illuminated safety switch in a suitable colour
http://www.gravitech.us/ilsaswwicogr.html

 

[petem]

The switch panel faces forward so the Portside switch is on the left and the S'board switch is on the right. The correct way around! LED's are bright enough (when they work).

I like everything to be OEM if possible but might consider something like this if I could find a water resistant switch. I am having a search to see if Carling or anyone else do a switch guard.

 

[Portofino]

Gotcha - thx
Thing is as said if you can,t see the illumination, what’s the point of it ?
Low voltage ( relay stuff ) could you move them out of harms way so to speak and site them in eyeline from the helm ?
And add a guard - cos it’s kinda important they are not accidental turned off .

 

[petem]

You CAN see the illumination but the light on one isn't working. As I said, will investigate a guard and / or remind my partners of the symptoms.

 

[Freeloader]

If you have one of the earlier switches, it will be illuminated by a small incandescent bulb. If so, replace it with one of the newer switch bases fitted with LEDs - ideally the 'superbright' LEDs, as the standard ones are a bit dim in daylight.

If you are unsure what is what, download the Carling PDF that explains what all the part number codes mean - if you can't find it, PM me and I will e-mail you a copy.

 

[petem]

If you have one of the earlier switches, it will be illuminated by a small incandescent bulb. If so, replace it with one of the newer switch bases fitted with LEDs - ideally the 'superbright' LEDs, as the standard ones are a bit dim in daylight.

If you are unsure what is what, download the Carling PDF that explains what all the part number codes mean - if you can't find it, PM me and I will e-mail you a copy.

Hi Freeloader, thanks, I've spent quite a while looking at the PDF and I think I have figured it out I think. I'll definitely have a look at the superbright ones as you suggest.

For the time being I'm more interested in what is causing the lamp not to illuminate. Providing it's at the switch end it will be easy to diagnose (just by test swopping the wires to the working switch) or with a multimeter.

 

[aquatom]

It’s quite common for water to get behind those switches on the Targa 34 and corrode the connections. The relays are located outboard if the port engine in two plastic boxes. Between them you will find the battery link solonoid. The switches for the bilge pumps do illuminate when the float is triggered.

 

[petem]

It’s quite common for water to get behind those switches on the Targa 34 and corrode the connections. The relays are located outboard if the port engine in two plastic boxes. Between them you will find the battery link solonoid.

The switches for the bilge pumps do illuminate when the float is triggered.

Cool, thanks Tom. If I remember correctly, the locker under the helm seat does suffer from corrosion due to the cockpit fridge compressor being in there. Definitely sounds the most likely culprit. I assume that the switch bodies just unclip from the little panel?

That would be these boxes! ...

I assume that the power for the lamp on the engine master switches could come from any part of the engine 12v circuit?

 

[jimmy_the_builder]

Carling do a version of the switch cap that includes a thumb lock, so you can't accidentally depress the rocker without sliding the thumb lock first. I had one on my P42, in truth it was a total pita but for your application it might be the right answer.

 

[stelican]

Carling do a version of the switch cap that includes a thumb lock, so you can't accidentally depress the rocker without sliding the thumb lock first. I had one on my P42, in truth it was a total pita but for your application it might be the right answer.

Yes seen these in use best and tidiest option for that application

 

[aquatom]

The feed for the LED comes from the switches side of the relay in the boxes in the engine room.
There should be a fuse for this supply to the LED but Fairline don’t fit one.

 

[petem]

Yes seen these in use best and tidiest option for that application

Jimmy / Stelican, I assume this is what you're referring to...

https://www.mudstuff.co.uk/carling-mom-off-mom-sp-with-safety-lock.html

Does look like it would solve the design issue noted above. Will give it some thought and speak to my partners (I still need to sort out the lamp issue).

Pete

 

[petem]

The feed for the LED comes from the switches side of the relay in the boxes in the engine room.
There should be a fuse for this supply to the LED but Fairline don’t fit one.

Brill, thanks Tom!

 

[Blue Sunray]

Jimmy / Stelican, I assume this is what you're referring to...

https://www.mudstuff.co.uk/carling-mom-off-mom-sp-with-safety-lock.html

Does look like it would solve the design issue noted above. Will give it some thought and speak to my partners (I still need to sort out the lamp issue).

Pete

The is a mom-off-mom so I don't think that it would be suitable here. Last year I was looking for an on-off with a safety which Carling do list, but I could not find in the UK at the time.

 

[petem]

The is a mom-off-mom so I don't think that it would be suitable here. Last year I was looking for an on-off with a safety which Carling do list, but I could not find in the UK at the time.

Remember mine switches an on/off relay so I believe mom-off-mom is correct (happy to stand corrected).

 

[petem]

It’s quite common for water to get behind those switches on the Targa 34 and corrode the connections. The relays are located outboard if the port engine in two plastic boxes. Between them you will find the battery link solonoid. The switches for the bilge pumps do illuminate when the float is triggered.

Tom, I measured the voltage for the feed to the lamp on the s'board switch and it's permanently ~13v (i.e. when the batteries are switched on or off). So I think I have two issues, something amiss at the relay end plus a defective lamp. Any idea what the issue could be at the relay? Unfortunately, being the s'board switch, the white box is aft most and therefore it's another lying on the engines job to get access.

I will replace both switches with the locking ones recommended above but obliviously need to sort out why the light is permanently on.

 

[petem]

Alternatively, does anyone know what relays Fairline used for the battery master switches?