Magnetic Level Probe Mk2

[TerryJC]

Penri,

Do you intend to swap this with the one at the WMT?

[Penri]

I’m going to complete bench testing this one and the other two I have in my workshop over the weekend then, all being well, look to retrofit the modification onto the probe in the sump early next week (Monday) if possible.

[TerryJC]

OK. That may well be easier than substituting the probe itself.

[Penri]

We now have 3 more working probes, though not yet inserted into waterproof tubes. The electronic assemblies have been marked with serial numbers S/N 002, 003 and 004. Tomorrow the intention is to bring the probe currently in WMT sump up to the same build standard and mark the internal electronics as S/N001.

[TerryJC]

Penri,

I decided to test the new Stage Butts Pi Interface with both of the probes that you provided. With the blue-topped one, everything seems to work fine and I can get reliable depth readings at all of the depths that I tried. In particular, I got good readings at 900, 925, 950 and 975 mm. With the black-topped probe I could get no readings above 875 mm and at other levels, I had difficulty finding the level.

Is there a difference between the two?

[Penri]

There shouldn’t be any differences, they both checked out ok on my analogue test rig. It’s entirely possible that, despite careful handling, one may have developed a fault. I’m back in the UK, as of this morning, so can test out the “iffy” probe early next week.

[Penri]

Just tried out the iffy probe on my test rig, as I recall you were not getting any dips in the DC level at 900mm and above, it appears to be ok here. Can you confirm that my understanding of the problem is correct, please.

[TerryJC]

I was getting (if I recall correctly), 1.44 V between 900 and 975 mm and then something very small above that.

Perhaps we can set it up again when I bring the Interface to WMT ans see if we can replicate the problem.

[Penri]

The top-most sensor is at 975, there's no Hall Effect switch after that.

Happy to bring the test rig in, but not until next week now as I'm away for the weekend.

[TerryJC]

I wasn't expecting to install the new Interface anytime soon, so it'll keep.