Chinese level gauges for our ship’s tanks.

By admin

Greetings sailors,

Today we are going to learn how to install level gauges for any of our ship’s tanks.

We are going to see it by installing it in freshwater tanks, but the procedure and devices are the same for any other tank, such as fuel.

All this, spending about 30 euros … More or less, half of what it would cost in a nautical store and much less than it would cost us to have them installed by a professional, who I do not doubt would do very well.


I am not going to deceive you, this level gauges is not a fundamental instrument either. Well, if you do not have one in the fuel tank, perhaps it is a fundamental element.

And having two freshwater tanks, which only had a small window to look inside and little to see to know how full they were … Well, I decided to set up some level gaugages.

For there I had to see how much water was in the tank ..

Shopping list
To start our installation we will need two fundamental parts:

The gauge itself, which will be the part that goes into the tank, and that we will buy the appropriate length to match our tank.
I bought one of these from Aliexpress, but you have similar ones here on Amazon too

The sensor for the tank

The next building block is the indicator. You have them in different colors and graphics here on Aliexpress or on Amazon, but the important thing is that they have to be both of the same standards.

Different indicators

There are two standards: 0-190 Ohm or 240-33 Ohm and both the sensor and the indicator will have to correspond to the same to work together.

And additionally, we will need enough two-wire cable, we can use a telephone cable, but I recommend using an 8-wire UTP cable like this one from Aliexpress or this one from Amazon that will be more useful to later add new devices in that area of the ship.

A few tools, too … which will include a drill and a drill crown of about 52mm, which is the diameter of the indicator watch. If you don’t have one, you can buy a very cheap set of them: either on Aliexpress, on Amazon, or on any hardware or DIY store.

The real crown .. not the one they planted in the video ..

Connection and tests

The connection corresponds to the diagram that comes with the indicator.

The truth is that, this time, it is quite clear.

The red wire to 12 volts from the boat’s battery.

The blue wire to the negative of the battery and to one of the two wires of the sensor (it does not matter which one).

The black wire to the other sensor wire

And you can connect the orange to the battery too, if you want the indicator to light up with a backlight.

I recommend doing like me and trying everything first, before installing it, to understand everything well.

You have all the details in the YouTube video.


We will have to locate the upper part of our tank, hopefully, there will already be a location prepared for the gauge with 5 holes corresponding to the SAE standard that our gauge meets.
If not, we will have to make a hole of adequate size.

In our case we had a window for a mechanical gauge … which we will remove, and we will clean the place where it was going.

Now we should be able to reuse the holes or make new ones.

When making the holes very carefully, if it is a fuel tank (especially gasoline) and it is metallic, the risk is high. Empty the tank and ventilate well.

Once the holes are made, we can cover the old ones with silicone, although the gasket will cover them in any case. We put the gauge in its place and put the screws.

In my case I have chosen to put them with screws and nuts because the other side is easily accessible … if not, especially if it is metallic, I would have threaded the holes so as not to need nuts, or I would have used stainless steel lag screws.

Now it’s time to lay the cable …
As always, on old ships… Quite an odyssey

If you are lucky, then there will be cable guides that will take you everything to the switch panel and stuff … But honestly … I don’t think you’re going to be lucky, so use all your imagination to take the cable to the place where you want to put the indicators. I have left you a list of my best tricks to pass cables in the video.

Finally, we have succeeded and we have the cable from the two gauges to the control panel … and, as we have used UTP cable, we have plenty of cables for future projects.

Looking for the right place, I have decided that I am going to put them on the side of the switch panel.

With the wiring already in place and the holes in place … we can start connecting the indicators, as we saw in the diagram.

For the 12V power cable, we can choose to connect it through a switch, or with a push-button, and that they only work when we press .. Or connect them to the switch on the panel of the water pressure pump, which is what I have done. And with the backlight, you can decide to use it or not.

The indicators working

Although it is not a fundamental instrument, having indicators of the levels of the water tanks is something really comfortable … before practically, my only indication was when one was emptied, it was passed to the other and I already knew that I had to refill soon.

So I would always notice while I was using the water and start blowing air out of the faucet.

Now I have it very controlled and I can decide how full the tanks were and how much water can be used at any given time.

For those of you who are not very handy, it is surely a simple step to start entering the DIY world of your boat.

Because doing it yourself, sometimes it is not so much saving, especially time, nor are you going to do it better than a professional …

But you are always going to get a couple of very important things:
The pride of having done it yourself and especially a deeper knowledge of your boat, that will help you in an emergency in which you cannot count on immediate help.

That in this nautical thing, as soon as you go a few miles from the coast, you are very alone for almost everything …