Fresh Water Tank Full Alarm

Last edited:
Sandy said:
Still I is great to see one of the late great Nigel's posts get resurrected after his death.
Click to expand...

Indeed great way to remember him.

Just wondering if these would make good bilge alarms? at that price you could have a couple in different areas.

Pete
 
Pete7 said:
Indeed great way to remember him.

Just wondering if these would make good bilge alarms? at that price you could have a couple in different areas.

Pete
Click to expand...

Remember one probe is positive, so if it is the water it will turn fresh water funny colours depending on material, or rot hull fitting due to galvanic corrosion.

Brian
 
halcyon said:
Remember one probe is positive, so if it is the water it will turn fresh water funny colours depending on material, or rot hull fitting due to galvanic corrosion.

Brian
Click to expand...

I guess that might be a jokey comment Brian ..... but assuming it's not, surely the circuit and probes are just a simplified ohm-meter so the current will be of the order of micro amps and not able to do anything untoward? :confused:

Richard
 
halcyon said:
Remember one probe is positive, so if it is the water it will turn fresh water funny colours depending on material, or rot hull fitting due to galvanic corrosion.

Brian
Click to expand...

Oops not doing that then, don't want to risk introducing a problem were none currently exists.

Pete
 
RichardS said:
I guess that might be a jokey comment Brian ..... but assuming it's not, surely the circuit and probes are just a simplified ohm-meter so the current will be of the order of micro amps and not able to do anything untoward? :confused:

Richard
Click to expand...

Many years ago I designed a low washer bottle sensor with two probes system, turned the water blue, found a chip that solved it only for it to go out of production. Solved it with a odd ball circuit, then lost interest in project until I used a two probe system for my water tank level check, got round it by adding a push to test switch which isolates positive supply.

The problem is 12 volt dc and water with negative connection to it, even a little current can cause corrosion.

Brian
 
halcyon said:
Many years ago I designed a low washer bottle sensor with two probes system, turned the water blue, found a chip that solved it only for it to go out of production. Solved it with a odd ball circuit, then lost interest in project until I used a two probe system for my water tank level check, got round it by adding a push to test switch which isolates positive supply.

The problem is 12 volt dc and water with negative connection to it, even a little current can cause corrosion.

Brian
Click to expand...

The device linked to by MacD is 3V max and with current of a few micro amps running only when the level reaches the probes I just don't believe that any adverse effects are possible. :confused:

Richard
 
babsash said:
...
.
Click to expand...
Just hold your horses. You did tack a bilge water question on to the end of a Tank Full thread that was started by a respected forumite who has since passed away.

Boat electrics can be quite simple and are worth getting a grip of. A float switch could be used to trigger an alarm better still to have a bilge pump with a float switch that can be left in automatic mode.

So take breath and enjoy good sailing in 2018.
 
RichardS said:
The device linked to by MacD is 3V max and with current of a few micro amps running only when the level reaches the probes I just don't believe that any adverse effects are possible. :confused:

Richard
Click to expand...

If you are happy fine, below 1 volt difference can cause galvanic corrosion. An elastic band round a sheet of stainless steel can cut a groove in the metal when in a suitable solution, due to the voltage difference between under the band and not covered by band.

It was justment as a caution to having live probes hanging in water.

Brian
 
babsash said:
...
Click to expand...

macd said:
He edited to "..." both his first post (with questions), and the later one in which he opined that we were a bunch of smartarses to whom he bid good riddance. I suspect he wasn't awash with festive spirit. Or perhaps he was.

Merry Christmas, Richard and all.
Click to expand...

Merry Christmas Mac. :)

Surely that has to be the shortest "first post to flounce" ever on YBW .... and for what? :rolleyes:

Richard
 
RichardS said:
Merry Christmas Mac. :)

Surely that has to be the shortest "first post to flounce" ever on YBW .... and for what? :rolleyes:
Click to expand...

It might be that he declared himself electrically phobic, to which I suggested that most users can do the electrical stuff on the OP's device with their eyes closed. Since they're blind, I thought that not unreasonable. ;)
 
halcyon said:
Remember one probe is positive, so if it is the water it will turn fresh water funny colours depending on material, or rot hull fitting due to galvanic corrosion.

Brian
Click to expand...
Not sure if a singe button cell at 1.4volt isolated from all else would cause any issues, it’s probably a capacitance probe anyway
 
macd said:
It might be that he declared himself electrically phobic, to which I suggested that most users can do the electrical stuff on the OP's device with their eyes closed. Since they're blind, I thought that not unreasonable. ;)
Click to expand...

Now it all makes sense. Apologies for being slow on the uptake there. ;)

I didn't even look at Nigel's link but only looked at your new one so the joke about "eyes closed" whooshed right over my head. I didn't take it as a snub though .... I just thought that it was you who were on the Christmas Spirit. :encouragement:

What a tangled web we weave. ;)

Richard
 
Curiously, some tanks have the vent inside the hull. I saw a boat nearly sink at dock when the owner left the hose run while he went to the store. The water was halfway up the companionway ladder.

In my case, the water just comer out the vent, which is below the fill. Easy.

Question for the day. Is there a screen in the vent to keep bugs out? The land code requires it, but many boats lack these.
 
You must log in or register to reply here.

Share this page

Top