Water tank gauge / sender mismatch

[neil1967]

I have recently bought a new Osculti water tank gauge, which has three connections on the back (Pos, Neg and Signal) plus a lighting connection, and the instructions show 3 connections to the sender unit (again, Pos, Neg and Signal); however, my sender units (probably VDO) only have 2 connections. Both gauge and sender are European resistance. Any ideas on how to connect the two units together?

 

[Refueler]

My senders were similar and gauge as well ... 2 wire and 3 wire.

Senders' 3rd 'connection' was the base plate of the sender ... which was -ve.

No g'tee for yours ... but hope someone can give more positive answer.

 

[neil1967]

My senders were similar and gauge as well ... 2 wire and 3 wire.

Senders' 3rd 'connection' was the base plate of the sender ... which was -ve.

No g'tee for yours ... but hope someone can give more positive answer.

Thanks, but unfortunately my senders are definitely 2 wire - the water tanks are inbuilt, in fibreglass, with no possibility of a ground connection :-(

 

[Refueler]

Can you give the ID / Model no's of Sender and gauges ?

Asking because of this as example :

VDO Fresh Water Level Sensor N02-240-802 Wiring and Setup

Pity that wire colours are not same text - diagram !!

 

[neil1967]

Can you give the ID / Model no's of Sender and gauges ?

Asking because of this as example :

VDO Fresh Water Level Sensor N02-240-802 Wiring and Setup

Pity that wire colours are not same text - diagram !!

It's about 37 years old, one of the type that had a float on the end of an arm that moved a potentiometer. Various markings, but the only one that is clear is 40/102.

 

[Refueler]

Mine is float on arm ..

But have a google ... as they are basically simple affairs as long as the + and - are not swapped over - its fairly easy to touch wires to see what happens ..

I did it by mounting the display (mine was fuel - but they are same for water) ... and having the sender next to it .. I wired the display as instructions then touched likely sender wires and got required response ... that was it. The -ve ground from display was connected to the mounting bolt of sender ... signal to signal in of display ... in fact thinking back that was it .. nothing more except display + and - to the respective power .. display provided power to the sender via signal - as the pot altered the ohms of the circuit ..

 

[Refueler]

Any joy ??

 

[Big John]

I fitted this to a friends water tank that had a VDO sender. The original sender and gauge were changed. The 2 wires from the old sender were used to send the resistance reading to the new guage and an additional neg lead was reqired on the new guage. The mounting hole and screw holes match exactly to the old VDO sender.

 

[PaulRainbow]

I have recently bought a new Osculti water tank gauge, which has three connections on the back (Pos, Neg and Signal) plus a lighting connection, and the instructions show 3 connections to the sender unit (again, Pos, Neg and Signal); however, my sender units (probably VDO) only have 2 connections. Both gauge and sender are European resistance. Any ideas on how to connect the two units together?

Connect positive and negative to the gauge. The signal terminal connects to one of the terminals of the sender. The other sender terminal connect to DC negative.

 

[neil1967]

Connect positive and negative to the gauge. The signal terminal connects to one of the terminals of the sender. The other sender terminal connect to DC negative.

Thanks Paul, very helpful.