Re: Liquid level indicator

Hi Chris

FF - yes of course, just didn't twig! Obviously, too much home brew
has killed some brain cells!

Thanks for the info about the MOV, I've heard of varistors, but never
knew what they were.

The relay is a tiny (ultra miniature they call it) PCB mount thing.
I'm not sure if the cover is removable. I can vandalise one as part of
'research' I suppose!

The .pdf file on the Maplin site is new - it wasn't there when I bough
my unit a few months ago. Would've been useful. I've been developing
a cct for temperature control using a PIC microcontroller which
interfaces to the FE33L, and spits out an RS232 signal for a PC to read
- I'm using the FE33 mainly as a tempsensor and LCD display - all of
which I'd probably implement using discrete components for version 2
now I've learned a bit about PIC's.

I did have a .pdf file of the manual for FE33L, but I can't find it (a
USB memory stick got trashed), otherwise I'd stick it on the web site.
If I get time, perhaps I can scan in the paper version. It's very low
on detail though, and certainly isn't a data*** and doesn't have a
schematic. It basically has two outputs for temperature control - too
hot or too cold, so you can control a heat and cool source.

By the way, the relay (YX97 - maplin) is rated to 10A

The temperature probe is the FE34M, and I have one of them. I wouldn't
want to put it in hot wort. Hence I'd like to make something from s/s
if that's at all possible.

I just looked through my Maplin order history, and I see that I ordered
RG23 500v 0.1uF capacitors, and also RG22Y Contact Suppressor 100R and
0.1uF in series 250v max.

Using your suggested 'relay logic' setup, would I need to put two
suppressors in the cct, one across each, or can I still stick with your
original suggestion of having these across the load? Any reason for
your change here?

The heat source will be controlled by RS#655-622, as will the pump.
Well, that's the intention anyway. But I am yet to decide on what to
use for the heat source. I haven't yet found my s/s containers for
this application, so the size will dictate the heat source to a certain
degree.

I was thinking about using an electric kettle element 2kW or similar.
I will be needing to heat about 25L of liquid from ~50C to 65C, fairly
rapidly, while recirculating with the pump.

Sorry Chris, what is GFCI?

I'm getting an old coal shed converted to use as the brewery, and it'll
have it's own consumer unit, earth rod and RCD main switch...

Cheers,
Mark

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