Electrickery stuff - what is this?

[WotEver]

Could it be a smoke alarm battery getting tired

I was wondering exactly the same thing.

[Robbo]

I was wondering exactly the same thing.

Reminds me of this story... http://www.dailymail.co.uk/news/article-2216177/Couple-driven-mad-incessant-beeping-pay-builders-tear-wall-discover-smoke-alarm-chest-drawers.html

[Wanderer Vagabond]

Could it be a smoke alarm battery getting tired

 

 

I was wondering exactly the same thing.

Nope, I can eliminate that as we've only got 2 CO2 alarms and no smoke alarm.

 

We did nearly have the Fire Brigade put our front door in though when I forgot to take out the batteries from the home smoke alarms when we came onto the boat, it was driving the neighbour crazy but she did tell the fire brigade that she knew we weren't in the property so they just left me a note through the door.

[ditchcrawler]

A crucial piece of info I forgot to mention is that when I had a new alternator fitted the marine electrician disconnected the Adverc as he claimed it would invalidate the warranty on the alternator( ) so if it is related to the Adverc it shouldn't be doing anything.

 

 

What voltage does your battery charge at without it?

[Wanderer Vagabond]

What voltage does your battery charge at without it?

Depends on the state of charge of the batteries, when down to about 88% it charges at something like 14.3v (I think) but obviously drops as the battery charges to 12 or 13 point something when nearly fully charged

[WotEver]

Depends on the state of charge of the batteries, when down to about 88% it charges at something like 14.3v (I think) but obviously drops as the battery charges to 12 or 13 point something when nearly fully charged

Summat wrong with them numbers.

[Wanderer Vagabond]

Summat wrong with them numbers.

Possibly since I only really note the SOC reading. Given the time of night I don't think I'll fire up the engine to see what it's charging at

[Wanderer Vagabond]

Ain't boats wonderful! After no 'pip' sounds since just before I posted this original query it decides to make a few 'pip' sounds today in the best place you can find for trying to locate it, in the middle of Braunston Tunnel . Having now emerged the sound has again stopped!

[magnetman]

I have heard of damp causing Carbon MONoxide alarms to go off. Maybe going through the tunnel increased the relative humidity in the boat?

 

Eta they usually chirp when battery is running out and I realise this may have been covered earlier in the thread anyway.

Edited May 2, 2016 by magnetman

[Tony Brooks]

Possibly since I only really note the SOC reading. Given the time of night I don't think I'll fire up the engine to see what it's charging at

 

I have had a quick scan through to see if you say what instrument is giving you a SOC reading and can not see it identified. If it is not a Smartguage could the problem be an alarm on an inverter responding to low battery voltage - i.e. the SOC gauge is lying.

 

Just a thought.

[WotEver]

 

I have had a quick scan through to see if you say what instrument is giving you a SOC reading and can not see it identified. If it is not a Smartguage could the problem be an alarm on an inverter responding to low battery voltage - i.e. the SOC gauge is lying.

 

Just a thought.

If it's an Ah counter then it's a rock solid certainty that it's lying.

[Tony Brooks]

If it's an Ah counter then it's a rock solid certainty that it's lying.

 

You could say that, I couldn't possibly

[WotEver]

[Wanderer Vagabond]

The meter that I'm getting the SOC reading from is the Victron BMV 600 battery meter which I'm aware isn't accurate however I'm assuming that when the charging rate drops below about 7- 8amps then the batteries are pretty much charged, whatever SOC may say. The inverter is a Victron combi 12v 1600w which has warning lights for inverter on(permanently lit unless on shorline)/overload/low battery/temperature. None of these lights are coming on when I get this irritating 'pip' sound. Soon after I got the boat (3 years ago) the batteries failed and the low battery light came on so it does work. At the moment I'm running for about 4 hours most days so would expect the batteries to be reasonably well charged.

 

It may be possible that the sound is coming from the inverter but if so I don't know what it is trying to tell me and since it only makes the sound intermittently, pinning down where it is coming from has been a problem.. I've got this feeling that it is going to be one of those things that I just plug on with until it breaks completely then I'll at least know what it is. The only thing I can add is that it only ever happens with the engine running and there are no smoke/CO detectors at that end of the boat.

[Sea Dog]

I'm assuming that when the charging rate drops below about 7- 8amps then the batteries are pretty much charged, whatever SOC may say.

Oooh, no, not really. With 440Ah of domestic batteries (by now maybe half that cos they're 7 years old and about to be changed) I'm looking at a tail current of between 1-2 Amps on my BMV. Keep going til you get a constant tail current figure and I expect you'll be closer to that than 7-8 Amps. The more you charge to below 100% the further out the SOC reading will get, so I always go by tail current to know when I'm charged. SOC is a very rough guide even when you know it's reset after a full charge. You might find Amp Hours used a handier indication, but to what you've used since stopping rather than what you've put back.

[WotEver]

Best rule of thumb when measuring tail current is to stop charging when the current doesn't drop over a period of an hour. So if it's 7A now and say 6.2A an hour later, keep going. If it's 3.8A now and 3.8A an hour later, stop charging.

[WotEver]

The meter that I'm getting the SOC reading from is the Victron BMV 600 battery meter which I'm aware isn't accurate...

Do how were you quoting "at 80% SoC"? If it's from the BMV then it could be anything.

[Wanderer Vagabond]

I seem to be getting bogged down in charging rates for the batteries when it doesn't really solve the problem of where the noise is coming from. If I had low charge on the batteries I would expect the warning lamp on the inverter to come on, as it did the last time the batteries failed, but there is no warning lamp coming on anywhere to go with the intermittent noise, that is where my problem really lies. If it is some sort of audible warning device that is activating it is a bit pointless if there is no visual evidence to show what may be failing. I think that the only way to solve this is to plug on and wait for something to fail so that I can at least find out what it is.

 

I am now reasonably confident that the photo that I produced at the start of the thread probably isn't responsible for the noise since I cannot see any reason for the Esperbacher to make any sort of noise if it isn't on and others have correctly identified the photo as the Esperbacher control box. The inverter is some 4 feet away from the photo location on the other side of the boat so any warning noises coming from there shouldn't sound as though they are behind the instrument panel. I think I'm just going to have to wait and see

[Sea Dog]

I seem to be getting bogged down in charging rates for the batteries..... If I had low charge on the batteries I would expect the warning lamp on the inverter to come on, as it did the last time the batteries failed,

Well, yeah, but that's because if you're using the SOC from a BMV to decide when to stop charging, you're slowly heading back there! So do still consider your charging regime. Sorry I can't offer any help on your noise though.

[Tony Brooks]

Based on this thread and if I had to make a wild guess I would suspect its the low charge/high temp/low oil pressure warning buzzer (as was suggested on the first page). I would disconnect the temperature sender (if your engine uses a high temperature buzzer) and run for a dew days to see if the chirping has gone away. If not repeat with the oil pressure. If that stops it the most likely cause is a faulty sender unit.

 

However it could still be an intermittent short to metal on the cables running from warning lamps/diode block/buzzer to the senders.

 

I am not sure that a blown diode (short circuit) in the diode block would give this symptom, I think it more likely that the warning lamps would illuminate in pairs with a single fault.

 

If the noise is still present I fear it will be an alternator fault despite the fact that you say there is no glow on the warning lamp. I think that to go further with this we need ACCURATE first start up and revving voltage and current, revving just before last shutdown voltage and current plus the rated output of the alternator(s). Oh, it could also be a slipping and gripping alternator belt.

Edited May 4, 2016 by Tony Brooks

[Wanderer Vagabond]

Well, yeah, but that's because if you're using the SOC from a BMV to decide when to stop charging, you're slowly heading back there! So do still consider your charging regime. Sorry I can't offer any help on your noise though.

I'm not really using the SOC to decide when to stop charging, it has usually gone to 100% over an hour before I stop I just use that fact that over the past 3 years 4 hours running during the day has been more than adequate to keep the batteries charged.

 

 

Based on this thread and if I had to make a wild guess I would suspect its the low charge/high temp/low oil pressure warning buzzer (as was suggested on the first page). I would disconnect the temperature sender (if your engine uses a high temperature buzzer) and run for a dew days to see if the chirping has gone away. If not repeat with the oil pressure. If that stops it the most likely cause is a faulty sender unit.

 

However it could still be an intermittent short to metal on the cables running from warning lamps/diode block/buzzer to the senders.

 

I am not sure that a blown diode (short circuit) in the diode block would give this symptom, I think it more likely that the warning lamps would illuminate in pairs with a single fault.

 

If the noise is still present I fear it will be an alternator fault despite the fact that you say there is no glow on the warning lamp. I think that to go further with this we need ACCURATE first start up and revving voltage and current, revving just before last shutdown voltage and current plus the rated output of the alternator(s). Oh, it could also be a slipping and gripping alternator belt.

 

Both the oil warning sender and temperature warning sender have both failed in the last 3 years and been replaced (£90 for a switch!! ) and when they failed it set the warning buzzer off. I don't think disconnecting them is going to help me much since this sound is so intermittent, I could go for a week without hearing it then it may happen several times a day so I wouldn't know if the absence of noise was because the sender was disconnected or because the sound had temporarily stopped.

[Tony Brooks]

I'm not really using the SOC to decide when to stop charging, it has usually gone to 100% over an hour before I stop I just use that fact that over the past 3 years 4 hours running during the day has been more than adequate to keep the batteries charged.

 

Both the oil warning sender and temperature warning sender have both failed in the last 3 years and been replaced (£90 for a switch!! ) and when they failed it set the warning buzzer off. I don't think disconnecting them is going to help me much since this sound is so intermittent, I could go for a week without hearing it then it may happen several times a day so I wouldn't know if the absence of noise was because the sender was disconnected or because the sound had temporarily stopped.

 

That is your choice but unless you work out a logical fault fining procedure you will just have to put up with the noise and hope its not something serious. Its unlikely but it could be water in the main harness multi-plug. Could you have vermin or a bird nesting in the boat?

 

It might be a drive belt squeaking, especially if a pulley has got dent/bow in it.

 

You need to prepare easy access to the whole area, including under the instrument panel so when it does start making the noise you can immediately start feeling and listening for the item that is doing it.

 

Try disconnecting the warning buzzer, you will still have warning lights and if the noise goes away you know its the buzzer. Then you need to isolate the circuit causing the fault. How will you do that?

 

I am going on about the warning buzzer because that often makes a chirping sound, as do smoke and CO alarms when the battery get flat. Could someone have put a gas alarm in or just above the bilge below the area of the photo. Could a smoke or CO alarm have been dropped or placed in the bottom of void that you photographed and been forgotten?

[mickp]

Is there a water detector in the bilge,if your cruising and a small amount of water is moving around it may momentry bleep.i had this happen with a small plumbing leak and even though i fitted the device years before i had forgotten it was there and was hunting for the beep

[Tony Brooks]

Is there a water detector in the bilge,if your cruising and a small amount of water is moving around it may momentry bleep.i had this happen with a small plumbing leak and even though i fitted the device years before i had forgotten it was there and was hunting for the beep

 

Another good thought.

[magnetman]

The point about it sounding in Braunston Tunnel.

 

Is the boat haunted?

 

It may be that you need Ghostbusters to sort it out.

 

Or it could be related to the extra load placed on a battery while tunnel light is on?

 

Could you have vermin or a bird nesting in the boat?

 

 

Birds make chirping noises. Maybe there is a coot nest under the engine? Nice and warm if it is used regularly.

Coots seem to be very successful in the current climate - I thought I had a coot nest in the bathroom until I realised the chirping sound was coming from a skin fitting connected to the wash basin !