Tweet
I am about to buy a DO metering equip. and I got a quote from Mettler toleldo, a hand held unit, model is "Seven Go pro DO - SG6-ELK", but I am not sure if this unit is made for measuring do in beer, I belive that it do not mease such small values that we are interested of. Anyone who knows better, Mettler toledos salesman was not sure about that.
-
-
Bjorn
Don't get this instrument. It will be the old technology Clark cell unit. MT don't do a hand held new technology unit (Optical quenching) yet.
If you want a unit for low levels of oxygen, up to 2 ppm, i.e. for use after fermentation has finished, then you can get portable units from Haffmans, Centec or Hach Lange.
If you want a unit for wort oxygenation only, then you can get instruments from Haffmans and Centec only.
If you want a unit that will give you good accuracy over both ranges, then the only option currently is Haffmans. They are supposedly range either 0 to 2000 ppb (billion) or 2000 to about 30,000 ppb (2 to 30 ppm). However, the high end unit I saw gave pretty good results down below 50 ppb.
The maintenance on these new systems should be hugely less than Clark cells, as there is no membrane to replace every few weeks. To keep recalibration costs down, you can use deoxygenated water, rather than buying in oxygen free gas, and use air for top end calibration.
Cost ? Several thousand Euros a go - probably a similar price to the Clark cell.
The Mettler units using the same technology should be out next year, the high end Hach unit should be out later this year.
Good luck with it. If you need any contacts, give me a call
Cheersdick -
Please allow me to make a couple of additions / clarifications to the previous post
Firstly, it sounds a little as if I am suggesting the MT Clark cell system is no good. Although I have never used one, I am certain it is very good, equal to or possibly better than others on the market
Secondly, it would be worth contacting Centec re the off line probes. Again I haven't seen the off line systems, but the inline systems only read within the defined ranges 0 - 2000 ppb, and 2000 to 30000 ppb. However, it is possible that they could easily be set to read outside these ranges, though with less accuracy guaranteed. The Haffmans atomatically reads outside the nominated range, but in smaller numbers to indicate is is not within the guaranteed range
Anton Paar also do sensors, though I am not sure if this is fully developed, and have not seen it in action to comment
For the bigger brewers out there who wish to use in-line sensors, all of these suppliers have instruments available.
CheersdickComment
-
I'm only interested in tests after fermentation: after transfering to lagering tank, after filtration, before bottling and the beer in bottle. I got a bit suspicious when I got the price, only 900 euro. The range is
DO range 0.0 ... 600%, 0.00 ... 99.00mg/L
DO resolution 0.1 ... 1%, 0.01mg/LComment
-
The range for this is about a 100 times too high. You need to be talking in low numbers of parts per billion, not parts per million.
Air saturated water contains about 10 ppm, oxygen saturated water about 30ppm, with typically 10 to 20 ppm for wort, but plenty of yeasts / beers need more, and some only need about 7 or 8.
My contact should either be in touch with you directly or get one of his colleagues to get in touch. The instrument that was originally suggested is simply not suitable for what we brewers need, particularly as you need to sample directly from a sample tap or similar. I'm really not sure what the instrument would be useful for.
You are likely to get offered a Clark cell type instrument which is somewhat cheaper to buy than the new optical sensors
Good luck
Anyone local you could share the purchase with, or hire from for short periods to at lest do an initial survey ?dickComment
-
I second Mr. Murton. Don't even bother looking at a meter unless it measures to the ppb range. If you want to measure package DO levels it's essential.
We currently use an Orbisphere DO meter. It uses the older membrane sensor which is troublesome to replace. It's reliable and steady once its up and running, but the replacement and calibration leaves something to be desired.
The new sensors are far less headache. I only wait until we can find a way to get one.Comment
-
Depending, naturally, on the budget you have available, I'd go for a straightforward instrument like the Orbisphere 3650 portable.
It is a known, well-used meter, robust and capable of withstanding the usual knocks of brewery life.
The membrane sensors, again, are simple to keep serviced and maintained and are easy to troubleshoot.
Certainly you need to be looking at instruments that reads - accurately - into the low ppb range. Depending on membrane selection, the 3650 will work for everything from wort aeration/oxygenation to brite/packaged beer.Comment
Comment