Sourcing A Small 2 Pole surface mounted switch

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C08

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I want to be able to short out the output from my wind gennie to stop it electrically and leave just solar charging for my batteries, through the controller. So I just want to break the 2 output leads and either connect them to the controller or short the output to stop it generating as advised by Marlec. So I am just looking for a small surface mounted 2 pole switch (a similar size to a small in-line electrical lead switch up to 3"x1.5" as this would fit nicely in a sub panel). Amazingly I cannot seem to fiind what I am looking for, plenty of panel switches of all shapes and sizes but little surface mounted. Even Acorn Engineering who a very good for obscure stuff, no joy. I have looked in Caravan Equipment Suppliers without success.
Any bright ideas?
 
What current rating do you need on this switch?

A panel-mount switch, either toggle or rocker, inserted in the lid of a small project box, would seem to fit what you’re after.

Pete
 
Project box is a good suggestion thanks. The wind gen is rated at 160W but I have never seen more than about 8amps from it so 10A switch rating should suffice. At least I am learning about switch protocols! It seems I need DPDT and ON - ON.
 
C08 said:
It seems I need DPDT and ON - ON.
Click to expand...

I suspect you don’t really need a double-pole switch - you could connect both the normal load and the resistor (or whatever your “brake” consists of, I don’t really know about turbines) to one side of the turbine, and then switch the other side between the two.

Pete
 
I want to do this too. The lady at Marlec was quite insistent that the required switch had to be "Make before Break", although to my inexpert eye the drawing that Marlec supplied didn't show this.
I have finished up with a system where to shut off the wind turbine, but keep using the PV panel, I have to shut off the switch on the HRDi Regulator, then switch off with the DPDT switch, then switch the regulator back on again for the PV panel. I don't know yet if it'll work, but I don't see why not.
 
I used eBay for one for an anchor chain counter project. Type ‘toggle DPDT’: that’s Double Pole, Double Throw’
 
NormanS said:
I want to do this too. The lady at Marlec was quite insistent that the required switch had to be "Make before Break", although to my inexpert eye the drawing that Marlec supplied didn't show this.
I have finished up with a system where to shut off the wind turbine, but keep using the PV panel, I have to shut off the switch on the HRDi Regulator, then switch off with the DPDT switch, then switch the regulator back on again for the PV panel. I don't know yet if it'll work, but I don't see why not.
Click to expand...

The Marlec customer advice people are excellent but I was not advised by them a couple of days ago that the 2 pole switch had to be make before break. Do you know why that is?
 
C08 said:
The Marlec customer advice people are excellent but I was not advised by them a couple of days ago that the 2 pole switch had to be make before break. Do you know why that is?
Click to expand...

Presumably it is the same as the motor alternator - it can burn out if there is no load. A conventional switch will have a microsecond when neither circuit is engaged as you switch over.

Methinks a bit OTT - but experts will probably tell you different
 
I have had a bit of a run of bad luck with my wind generators. My 913 flew apart in a gale in the summer before last. It's a mizzen mast mounting, so not as readily accessible as one mounted on a pole. Suddenly the whole mizzen mast began to vibrate, indeed it felt as if the whole boat was shaking. Presumably the turbine had lost a blade. I can only guess, because before I could do anything, there was a terrific bang, and the whole rotating element disintegrated and flew into the sea.

It wasn't until the next day that we discovered that some heavy metallic part had actually struck a part of the elliptical section stainless steel aft bulwark rail, severely distorting it. Still, it could have been worse, if this part had struck the deck, or my head, it would probably have gone right through it. I think it was part of a disc of permanent magnet, as there was a broken bit of it remaining.

I was in two minds about replacing the wind Genny, but she who wants the fridge on 24/7 was very persuasive. By this time Marlec had ceased making the 913, and was marketing the 914i in its place. I was assured by Marlec that all its physical dimensions were identical, and that a 914i would fit in place.

Only when sitting in my bosun's chair up the mast, did I discover that the mounting spindle was very slightly too big to fit into the mast fitting. Back down with both me and it to grind a bit off it. Back up with it, and all well, cables joined, and then found that the tail fin is about 50mm longer than the old one, and so it was fouling the mast. Back down again, and sawed a bit off the tail fin. To be honest by this time, I was finding it difficult to stay cheery.

To cut a long story short, since then I have had a burned out HRDi regulator, which I thought was "just one of these things", and simply replaced. But more suspiciously, twice since then the turbine has developed excessive noise, and twice it has been sent back to Marlec, who have twice repaired it FOC. I assumed it was a problem with bearings, but Marlec said no, it wasn't bearings, but have declined to say what the problem had been.

The HRDi regulator can cope with the wind turbine and also up to 160w PV panel. I have a 100w panel, and would like to be able, at times, to shut down the turbine but keep the panel operational, for instance if the boat is left on her mooring for some time. I enquired about doing this and was given a wiring diagram by Marlec to show how to achieve this. Basically it is just a short between the +ve and -ve from the turbine.

Further correspondence with Marlec, with Sarah Tomes, Technical and Sales, in which she stated that it is vital that the switch installed to switch off the turbine, while maintaining the use of the panel, must be "make before break". (She actually said brake, but I got the message). It was a mate of mine who actually made up the switch for me, and I do not actually know if mine is make before break, so my solution (agreed with Sarah Tomes) is to switch off everything with the switch on the regulator, then switch off my DPDT switch, then switch the regulator back on to get the use of the PV panel.

Marlec took rather a long time to return the unit to me this last time, so I missed the opportunity that I had to get it back up, so I cannot say with any certainty that everything works as it should.

Apologies for such a long post.
 
Thanks for the explanation Norman it is very helpful to me to have this info. Sorry to hear of your tribulations with your 913 and two controllers. My 913 has run continueously since 2007 controlled by the older HRDX controller, also handling 80W of Solar Panel charge. I like your routine of shutting down the controller, switching off the wind gen and then turning back on the solar only. Good sailing (and charging ) to you!
 
NormanS said:
To cut a long story short, since then I have had a burned out HRDi regulator, which I thought was "just one of these things", and simply replaced. But more suspiciously, twice since then the turbine has developed excessive noise, and twice it has been sent back to Marlec, who have twice repaired it FOC. I assumed it was a problem with bearings, but Marlec said no, it wasn't bearings, but have declined to say what the problem had been.
.
Click to expand...
Following a problem with their bearings a friend of mine spent some time researching the subject & actually contacted SKF's tech dept. The bearings Marlec use do not have the correct shielding & when my friend tried to explain this to their management they seemed totally incapable of comprehending the fact. He knew he was right because he had confirmed all this with SKF. It is to do with the way the shield fits into the bearing to make it watertight.It has been explained to me but i do not recall the precise details.
His unit has been back a couple of times due to bearing failure which I believe that they deny each time.
 
Daydream believer said:
Following a problem with their bearings a friend of mine spent some time researching the subject & actually contacted SKF's tech dept. The bearings Marlec use do not have the correct shielding & when my friend tried to explain this to their management they seemed totally incapable of comprehending the fact. He knew he was right because he had confirmed all this with SKF. It is to do with the way the shield fits into the bearing to make it watertight.It has been explained to me but i do not recall the precise details.
His unit has been back a couple of times due to bearing failure which I believe that they deny each time.
Click to expand...

That's interesting. I know they had bearing problems in the past, and assumed that my "noise" was bearing related. They denied this, but went very coy when I asked what the problem had been. The man with whom I had previously dealt was very good, but he has apparently moved on......

With ours being mounted up on the mizzen, and us sleeping in the aft cabin directly underneath, any noise from the Genny comes straight down to us.
 
I have been trying to remember my friend's description of the sheilds & having slept on it I think it was something like this:-
Imagine one side of the bearing. Normally there is one shield rather like a plastic washer
On the special bearings there is 2 shields. One connected to the outer metal part & one connected to the inner part. These overlap where they meet in the center of the circumference. Where they overlap they are folded over each other to form a sort of hook as if 2 hands were holding each other.
The same is on the other side of the bearing so the bearing effectively has 4 pieces to make up the 2 shields
He did explain how the 2 bits rotate against each other but began to loose me at that point. I does seem that SKF say that these should be specified for the Marlec installation. They are designed for waterproofing in environments such as the salt water one on a boat
 
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