I would like to ask fellow sailors: there’s something wrong with our magnetic flip-type level gauge. Could someone please explain what’s going on?
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Our magnetic float level gauge is acting weird. Some time ago we noticed that there was a problem with it – the display stopped working quickly. We assumed that the magnetic float itself was the issue, so we opened it up for inspection and found that the float was damaged and water was getting inside it. Since there were no spare parts available, we simply glued the old float back in place and used it again. Three days later, the level indicator stopped working again; since we already knew it was a problem with the float, we didn’t try to fix it any further. Strangely enough, in the past two days the level indicator has worked intermittently; I’m really confused. Could someone please explain what’s going on? The float is made of aluminum, and the medium being measured is ammonia
Theoretically, if the float is damaged and liquid completely enters it, it will sink to the bottom with no level indication； If liquid is introduced only partially, it may occur that the level indicator shows a low level while the actual level is not low ； If the liquid level is intermittent, it means the float is floating at the bottom but sometimes rises and sometimes sinks; as long as there is a indication of a liquid level during these intermittent periods and that level is low, it indicates that the float has sunk to the bottom.
When the liquid level is low, the water inside the damaged float also flows out; as the liquid level rises, it too rises. But over time, it will fall down. It’s as if a ghost has taken control of it.
If you know there’s a problem with the float, seize the opportunity to address it right away
It’s probably caused by changes in pressure inside you
I agree with this explanation. You can use a magnet to check the position of the float when there is liquid present, and then check it again when there is no liquid – that way you’ll know the actual position of the float.
When working with instruments, you can’t be careless – if it doesn’t work, then it simply doesn’t work. Trying to fix it by using glue isn’t a good idea. Ugh, that’s quite creative indeed; it would be better to have a technician take a look and see if the float can be repaired or welded back together – that would be much better.
The analysis on the second floor is correct; it involves looking for the cause in the instrument itself. If we go a step further, we can also consider factors related to the process. Another possibility is that fluctuations in the process medium occur when the float is not fully filled with liquid. We have encountered such situations before – there were fluctuations in the liquid level readings of the ammonia tank, but all other aspects of the process remained stable. The level stopped fluctuating as soon as the root valve was closed, but this phenomenon couldn’t be fully explained from a process perspective.
Buy a float and install it; it doesn’t cost much.
I agree with what was said on the second floor – this explanation is based on the perspective of the instruments, but I still have some doubts. If liquid enters the float, it will only keep increasing, and it’s unlikely that there will be fluctuations in the float’s position. It would be easier to explain this from a process perspective. I encountered a case where there were fluctuations in the liquid level of an ammonia tank, and it was suspected that the instruments were inaccurate. When we closed the valve at the base of the instrument, the fluctuations stopped; when the valve was opened again, the fluctuations resumed. In fact, it was a problem related to the process itself. In the example given by the original poster, it can be inferred that the float was leaking first, but another possible cause could be that the liquid level of the ammonia indeed was fluctuating.