Barrus Shire ignition switch

[Eeyore]

The forum software keeps combining my posts, not sure if a notification is sent each time, ho hum.

Terminal 75 is usually radio/cigar lighter

Terminal 83 is the common contact on normally closed or changeover switches.

Probably worth checking for voltage on all the wires when disconnected.

The reason for Barrus choosing such a switch may never be known, but I find myself drawn to the words "bargain bin" 😗

 

 

[Mike H]

Ok I have checked the difference between the switches and it is terminal 83.  With the BS switch there is continuity to 83 from 30 even with the ignition off.  With the Durite switch there is no continuity to any terminal with switch off.

 

Now I need to check where 83 is connected to. I think they are to the warning lights and rev counter.  I need to double check this when at the boat tomorrow.

 

I know 75 runs to the split charge so no nearer why it should overcharge with the Durite switch fitted.

[ditchcrawler]

20 minutes ago, Mike H said:

 

 

I know 75 runs to the split charge so no nearer why it should overcharge with the Durite switch fitted.

Do you have some fancy alternator controller like battery sensed that is not connecting properly ? 

[Tracy D'arth]

I have had this problem with a Barrus before. Not the switch but the supposedly 90A alternator (really a 80A Mitsubishi)  going berserk and pushing out 16.5V.  Took a bit of searching to find the equivalent.

I hope that yours is not the same problem.

[Tony Brooks]

4 hours ago, Mike H said:

Ok I have checked the difference between the switches and it is terminal 83.  With the BS switch there is continuity to 83 from 30 even with the ignition off.  With the Durite switch there is no continuity to any terminal with switch off.

 

Now I need to check where 83 is connected to. I think they are to the warning lights and rev counter.  I need to double check this when at the boat tomorrow.

 

I know 75 runs to the split charge so no nearer why it should overcharge with the Durite switch fitted.

 

I wonder if your alternator is a six diode machine, being Mitsubishi that is possible. Six diode machines often need a direct ignition geed, separate from the warning lamp for energisation, and I think (don't know for sure) that the direct ignition feed is also the sense wire. If that is not energised, then the regulator would see zero voltage and default to a maximum, hence the overcharging.

 

How are the alternator terminal designated?

 

I would need to investigate the boat to be sure.

Edited May 6, 2023 by Tony Brooks

[Mike H]

I understand the ideas regarding the alternator/ regulator/rectifier overcharging but the problem occured only  with an INCORRECT IGNITION SWITCH FITTED, the engine off, boat in marina on shore power and 200w of solar on the roof. This would seem to rule out a fauly alternator which would only overcharge when engine running? or am I missing something?

 

Basically I am trying to replace an intermitantly working BS ignition switch with a new one. It was the incorrect Durite switch which caused overcharge. So change back to the original wonky BS switch all is well again with battery voltages now back to normal.

 

So it is probable we do not have a fault other than trying to use the wrong switch (Durite) This leads back to previous posts in this thread with posts discussing why you can't use a non BS switch and we are back at square one !!

 

We have owned the boat for nearly two years with no overcharging or electrical issues. Out of interest I will add my boats wiring diagram later to see if that helps a better person than me, I am a reasonably competent amateur, to understand what the switches are doing.

Edited May 7, 2023 by Mike H

[David Mack]

18 minutes ago, Mike H said:

but the problem occured only  with an INCORRECT IGNITION SWITCH FITTED, 

Or with a suitable but non-original switch incorrectly fitted.

If using an alternative switch, one would hope that the functionality would have been checked and the connections made accordingly, rather than just blindly fitting the spade terminals in a way that looked the same as before.

[Tracy D'arth]

37 minutes ago, Mike H said:

I understand the ideas regarding the alternator/ regulator/rectifier overcharging but the problem occured only  with an INCORRECT IGNITION SWITCH FITTED, the engine off, boat in marina on shore power and 200w of solar on the roof. This would seem to rule out a fauly alternator which would only overcharge when engine running? or am I missing something?

 

Basically I am trying to replace an intermitantly working BS ignition switch with a new one. It was the incorrect Durite switch which caused overcharge. So change back to the original wonky BS switch all is well again with battery voltages now back to normal.

 

So it is probable we do not have a fault other than trying to use the wrong switch (Durite) This leads back to previous posts in this thread with posts discussing why you can't use a non BS switch and we are back at square one !!

 

We have owned the boat for nearly two years with no overcharging or electrical issues. Out of interest I will add my boats wiring diagram later to see if that helps a better person than me, I am a reasonably competent amateur, to understand what the switches are doing.

So the excessive voltage can only have been generated by your solar.

I fail to see how the switch could cause the solar controller to malfunction. 

[Tony Brooks]

5 minutes ago, Tracy D'arth said:

So the excessive voltage can only have been generated by your solar.

I fail to see how the switch could cause the solar controller to malfunction. 

 

It also makes no sense to me. There should be no connection between the solar charging system, any mains battery charger, and the ignition switch. After all, both probably spend more time doing their thing with the ignition turned off than on.

 

It is a mystery, I fear a lot of wire tracing and diagram drawing is the only way to solve this one.

 

I agree with David M, in that this may involve some weird wiring and connection onto the new switch not being made by function, but by "look".

[Mike H]

12 minutes ago, Tracy D'arth said:

So the excessive voltage can only have been generated by your solar.

I fail to see how the switch could cause the solar controller to malfunction. 

No, because it was on shore powef as well at the time.

[Tony Brooks]

3 minutes ago, Mike H said:

No, because it was on shore powef as well at the time.

 

I fail to see how the switch could cause the mains charger/charger inverter to produce over voltage.

[Mike H]

Ok right here we go.  I have attached below my wiring diagram if anyone is interested in looking what is connected.  The rest of the diagram to the right is 'house' wiring and is not relevant to the issue.

 

As far as I am concerned now all is fine and I have established that a Durite replacement ignition switch is not suitable for my boat, as to why I will let others discuss.

 

Edited May 7, 2023 by Mike H

[David Mack]

That shows a very simple ignition switch. Terminal 30 is connected to the engine battery positive (via the engine battery isolator and a 15A fuse). Terminal 50 is connected to the start solenoid, so should only be energised in the 'start' position. Terminal 75/15, energised in the 'start' and 'run' positions, is connected to the Sterling Alternator Controller, to the alternator warning light (and from there to the alternator) with a separate connection directly to the alternator's internal regulator. All of those connections could be replicated with any generic ignition switch.

I notice there don't seem to be any heater plug connections. Does this engine not have them?

Edited May 7, 2023 by David Mack

[Mike H]

No, it's a BS 1552 3cyl direct injection so no heater needed. Starts first time every time !!

[ditchcrawler]

3 hours ago, Mike H said:

I understand the ideas regarding the alternator/ regulator/rectifier overcharging but the problem occured only  with an INCORRECT IGNITION SWITCH FITTED, the engine off, boat in marina on shore power and 200w of solar on the roof. This would seem to rule out a fauly alternator which would only overcharge when engine running? or am I missing something? 

I am sorry but if you are using an external charging source that should be regulated at the correct voltage I cant see ho any switch anywhere on the boat could cause overcharging

[Mike H]

49 minutes ago, ditchcrawler said:

I am sorry but if you are using an external charging source that should be regulated at the correct voltage I cant see ho any switch anywhere on the boat could cause overcharging

 

Neither can I.  Shore power goes through 3 way selector switch through AC trip/isolate unit  and also check circuit with lights that AC is on and polarity ok then to Sterling 30 amp charger.  No error lights on the charger so that is functioning correctly

 

I also can't understand why BS ignition switch is internally wired live from T30 to T83 when my boat elec diag and the official BS diagram do not show any live connection

[Tony Brooks]

Thank you.

 

Before I go on, I must make it clear that I do not disbelieve you, but it makes no sense.

 

It looks to me as if the Gy cable on 75/15 will act as a sense cable, so if it is not connected, the alternator would probably run uncontrolled at a default maximum voltage.

 

As expected, there are no connections shown between the ignition switch and the solar controller or charger.

 

The Y cable on 75/15 might also be a voltage sense cable, but again, that will only affect the alternator

 

[Tracy D'arth]

23 minutes ago, Tony Brooks said:

Thank you.

 

Before I go on, I must make it clear that I do not disbelieve you, but it makes no sense.

 

It looks to me as if the Gy cable on 75/15 will act as a sense cable, so if it is not connected, the alternator would probably run uncontrolled at a default maximum voltage.

 

As expected, there are no connections shown between the ignition switch and the solar controller or charger.

 

The Y cable on 75/15 might also be a voltage sense cable, but again, that will only affect the alternator

 

None of this makes sense. The only reasons that the batteries can be overcharged are, 

 

1  Alternator control lost, but you say it does this without the engine running.

2  Solar controller faulty.

3  Battery charger faulty.

 

I can see no reason why the ignition switch should cause any of thes if the connections are correct.

Only the alternator will have a sense wire but you say this is not the cause.

 

So which is it?

[Mike H]

I am waiting for a brand new BS ignition switch in the hope this solves the problem.  If this does not do it I will wave the white flag and call in a marine sparky.

 

Anyone in the area of Great Haywood Junction that would be interested in a job DM me.

[David Mack]

You haven't been reading the responses to your thread! There is nothing about the ignition switch which can cause the battery to overcharge. So whatever the problem is, just changing the gnition switch isn't going to make any difference.

[Tony Brooks]

1 minute ago, David Mack said:

You haven't been reading the responses to your thread! There is nothing about the ignition switch which can cause the battery to overcharge. So whatever the problem is, just changing the gnition switch isn't going to make any difference.

 

But he says the switch he is using is broken, and the Barrus one he replaced it with also broke. I think it was a mechanical fault within the switch(es). The overcharging thing is probably not connected to the mechanical fault(s).

[Mike H]

42 minutes ago, Tony Brooks said:

 

But he says the switch he is using is broken, and the Barrus one he replaced it with also broke. I think it was a mechanical fault within the switch(es). The overcharging thing is probably not connected to the mechanical fault(s).

 

This is correct, a mechanical switch fault  could cause all manner of wrong internal connections. Running with original BS Switch at the moment which is very 'graunchy' when turning from 'off'to 'ignition' with very little spring pressure evident on the key turn

 

The overcharging only occured with the Durite switch fitted. Voltages now running at 13v with engine off and 14v with engine running so thats OK

 

As I said now just waiting for new BS switch

Edited May 8, 2023 by Mike H

[Tracy D'arth]

Pure guess but I suspect that there must be a wire that is not connected with the Durite switch fitted. I still cannot understand why this would result in overcharging and would love to know the answer as logic has failed to give me a solution.

 

There must be  a sensing wire to Battery+ not connected somewhere but why solar and battery charger are affected but not alternator is beyond me.

[Eeyore]

It has to be said that neither of the wiring diagrams appears to reflect the reality as shown in the photos as regards the ignition switch wiring; terminals or colour coding. The "detailed" drawing shows what is basically the simplest wiring for a standard switch (given the accessories fitted), and the Barrus drawing is in no way applicable to this setup, being a current production item with twin alternators and timer relay (and certainly not the same switch).

I've asked for a list/table of the wiring terminals/colour/destination, because without that its impossible to see what has been done to the wiring to create this "fault". 

I'm guessing the boat is at the marina?

[Tony Brooks]

7 minutes ago, Eeyore said:

It has to be said that neither of the wiring diagrams appears to reflect the reality as shown in the photos as regards the ignition switch wiring; terminals or colour coding. The "detailed" drawing shows what is basically the simplest wiring for a standard switch (given the accessories fitted), and the Barrus drawing is in no way applicable to this setup, being a current production item with twin alternators and timer relay (and certainly not the same switch).

I've asked for a list/table of the wiring terminals/colour/destination, because without that its impossible to see what has been done to the wiring to create this "fault". 

I'm guessing the boat is at the marina?

 

That is why I said that the wiring needs tracing and a diagram drawn, showing how the boat is now, rather than some generic diagram.

 

I note that the diagram supplied has a Sterling alternator controller plus a Smartbank system, it is complicated.