Grey water tank sender switch

[lanerboy]

I need to replace the sender unit on my grey water tank it uses a float type where when the tank is full it triggers the pump to turn on and empty the tank.
I'm struggling to find the exact same one which is a velco B77 type unit and I can't find a price anywhere.

Has anyone replaced a side mounted float switch and if so what did you go for.

It's a two wire sender unit so I'm presuming any two wire sender will work once the float reaches a height to make the contact to turn the pump on, am I correct or is there more to it than this ???

 

[rafiki_]

I need to replace the sender unit on my grey water tank it uses a float type where when the tank is full it triggers the pump to turn on and empty the tank.
I'm struggling to find the exact same one which is a velco B77 type unit and I can't find a price anywhere.

Has anyone replaced a side mounted float switch and if so what did you go for.

It's a two wire sender unit so I'm presuming any two wire sender will work once the float reaches a height to make the contact to turn the pump on, am I correct or is there more to it than this ???

Mine uses the Whale solid state float switch. According to JFM, the work of the devil. I carry a spare as back up. Sorry, not much help this time.

 

[lanerboy]

Mine has the whale Gulper 320 pump fitted externally which pumps the tank out when the sender unit float triggers the pump to activate

 

[rafiki_]

Mine has the whale Gulper 320 pump fitted externally which pumps the tank out when the sender unit float triggers the pump to activate

Yep, mine is the same but with the Whale float switch.

 

[Skipper Felice]

Hello All

I looks that I have the same issue - problems with the sensor of the grey water tank:

What do you recoment to use as a reliable professional sensor?

 

[vas]

not quite answering OP issue, but over the last 10yrs I've managed to burn 2-3 solid state float sensors (one was for the whale grey tank that rafiki and others mentioned)
I have developed a theory that these things fail after repeatedly running de-sulphation on old school FLA batteries (in my case Trojans) I had (as recommended!) running them at 30.5V (24V boat) for an hour every couple of months or so and that seems to have triggered their death.
Over the last 4+ yrs with LifePO4, nothing has gone wrong...

 

[Dogone]

I’ve had no luck with any switch. Whale or the cheap float switches. They all seem to hate water and croak as soon as they get wet. I’m using the cheapo switches now and have lots of spares. Boating life…

 

[wonkywinch]

I've just fitted a Gobius tank sensor to my black water tank. It works using sound sensors on the outside, no moving parts. The controller has low current switching outputs so could be used to switch a pump relay.

Different versions available inc water, fuel multiple levels etc.

Instructions - Gobius