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  • #16
    The Milwaukee result is credible, maybe slightly high but depends on temperature. If your meter always read around 27ppm on tap water even before you calibrated it, then there certainly sounds to be a problem.

    Just to confirm, you are regulating the gas flow rate before the meter and flowing this through with no restriction at the outlet side?

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    • #17
      Yes, we are using the flowmeter to throttle down flow before the DO meter. The only restriction would be the slight restriction of the ~4 feet of tubing connected to the out on the meter. The tubing was supplied by the manufacturer. The meter reads our compressed air at 8-9 ppm after calibration, which is what i would expect. But the 27ppm coming out of the tap and samples from our fermenters pre-pitch is really throwing me for a loop.
      Last edited by Junkyard; 01-14-2018, 12:56 PM.

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      • #18
        I was half joking about having the air compressor next to a de-gassing tank, I wouldn't think this would be a likely issue in 99% of cases.

        At this point, in your shoes, I would feel confident in thinking the Beverly is not functioning properly. As TL said, the Milwaukee reading seem realistic. You have gone through calibration as carefully as possible, and frankly if it requires more than that, the instrument becomes more cumbersome than it should be.

        I would say your last option before abandoning the Bev would be to ask for Hamilton to ship you another new unit and return the faulty one for their in house testing purposes. If they aren't willing to do that, then I would ask for a refund (and opt for the Pentair/Haffmans, Orbisphere or other). As I have said before, I find these units have typically worked well for me, but I have not had the issues you are experiencing. Good customer service would swap the unit to keep you happy with their product.

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        • #19
          Originally posted by UnFermentable View Post
          I was half joking about having the air compressor next to a de-gassing tank, I wouldn't think this would be a likely issue in 99% of cases.

          At this point, in your shoes, I would feel confident in thinking the Beverly is not functioning properly. As TL said, the Milwaukee reading seem realistic. You have gone through calibration as carefully as possible, and frankly if it requires more than that, the instrument becomes more cumbersome than it should be.

          I would say your last option before abandoning the Bev would be to ask for Hamilton to ship you another new unit and return the faulty one for their in house testing purposes. If they aren't willing to do that, then I would ask for a refund (and opt for the Pentair/Haffmans, Orbisphere or other). As I have said before, I find these units have typically worked well for me, but I have not had the issues you are experiencing. Good customer service would swap the unit to keep you happy with their product.
          The rep is asking me to recalibrate the low end with 99.999% research grade n2. Says thats why we are experiencing these issues. He says they have never had an end user with a problem with any of their units to date.

          What you said about cumbersome functionality really nails it on the head for me. Its a portable DO meter that cost $7k this thing better be pretty damn functional.

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          • #20
            If you can find the "zero" gas N2 at a reasonable price in a small cylinder, then I would give it a shot, but I HIGHLY doubt this is going to make any difference. My guess is a faulty unit/sensor and I would ask first if they will take it back and calibrate it in house since you are having such issues. Again, good customer service would take care of your concerns.

            I would push saying I want a refund if they don't accept that as a reasonable option. They will probably take it, see the issue, replace it and tell you it worked fine all along, but at least then you will have an operational unit. You could also ask them if they are willing to refund your dollars for both the unit and the gas if the pure N2 calibration doesn't make a difference.

            Also, tell everyone who you are dealing with if they don't fix the issue so that they feel a little peer pressure to do the right thing. Gusmer Enterprises? or are you dealing with Hamilton directly?

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            • #21
              Before going to the time/cost of sourcing grade 5 N2, just run some good-quality CO2 or N2 through it to see what it reads on a low-O2 medium. I seem to recall you got low results from it and it's the high end that's just way too high?

              The only way I can see that using high-purity zero gas will help is if your current supply is massively high in O2. It would depend on the calibration protocol internally - ie. how the unit realigns the response graph - as to whether this would make the difference or not.

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              • #22
                Originally posted by Junkyard View Post
                We are using grade 2 co2 99.9% to calibrate currently. We then measured a dry Hopped IPA at 0 PPB. And measured tap water alongside an inexpensive milwaukee membrane DO meter (the milwaukee read 13.5 ppm, the beverly read 26 ppm.

                We then went back to the same co2 source we calibrated with and it measured 26 ppb. (Is this an acceptable error range?)
                Do i ask the manufacturer to take it back?
                I think that the gas does make a difference. If you are using 5-9 gas, you are much more likely to hit the low end. You are essentially trying to calibrate a zero point with possibility of <100ppb O2 in the gas. The number of nines after the decimal place are very important for purity. It's more expensive, but more accurate.

                At 99.9% gas is not certified to a 0.01% purity, which equals 100ppm. There could be UP TO 100ppm of another gas in there, making your calibration real whacky. See this from Merck: http://www.merckvetmanual.com/append...pb-conversions

                Hope this helps! Cheers - Madeline

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                • #23
                  Originally posted by UnFermentable View Post
                  If you can find the "zero" gas N2 at a reasonable price in a small cylinder, then I would give it a shot, but I HIGHLY doubt this is going to make any difference. My guess is a faulty unit/sensor and I would ask first if they will take it back and calibrate it in house since you are having such issues. Again, good customer service would take care of your concerns.

                  I would push saying I want a refund if they don't accept that as a reasonable option. They will probably take it, see the issue, replace it and tell you it worked fine all along, but at least then you will have an operational unit. You could also ask them if they are willing to refund your dollars for both the unit and the gas if the pure N2 calibration doesn't make a difference.

                  Also, tell everyone who you are dealing with if they don't fix the issue so that they feel a little peer pressure to do the right thing. Gusmer Enterprises? or are you dealing with Hamilton directly?
                  Yes we are dealing with Gusmer, who havent been the best to deal with so far.

                  I figured we are going to have a DO meter at our brewery whether its a hamilton or a hach i’d like to have some good high quality calibration gas, so i called our gas supplier and they stock a spec nitrogen thats 99.998% its 4.8 spec
                  Linde is an industrial gas and engineering company supplying Nitrogen, Hydrogen, Oxygen, Argon, Xenon, Acetyline, Carbon Monoxide, Helium, Neon, Krypton, Carbon Dioxide and More

                  I got a 300 cf tank exchanged for $100, which i thought isnt bad. And then gusmer cant say anything about my low quality gas.

                  I plan to ask for a refund if this doesnt work as the rep said it would, and possibly upgrade to a hach.

                  Originally posted by TL Services View Post
                  Before going to the time/cost of sourcing grade 5 N2, just run some good-quality CO2 or N2 through it to see what it reads on a low-O2 medium. I seem to recall you got low results from it and it's the high end that's just way too high?

                  The only way I can see that using high-purity zero gas will help is if your current supply is massively high in O2. It would depend on the calibration protocol internally - ie. how the unit realigns the response graph - as to whether this would make the difference or not.
                  The low end is reading a bit whacky too. We calibrated it to our manual with our beverage co2 last week and we had dry hopped beers reading 0 ppb. Then 30 min later we came back to the same bottle of co2 and it measured 25 ppb. I just dont think the meter we got is accurate on either low or high end. The low end is at least somewhat believable though.

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                  • #24
                    update:

                    We just calibrated with 4.8 spec N2 as outlined by our instructions from gusmer. the N2 should be 99.998% purity. calibration proceeded well for the meter. tap water read >25ppm still and we pulled a few cans off the line from an IPA canning run that both read 0 ppb, one of them was just seamed and one was a low fill that had been sitting for an hour which should have gave us some sort of reading. both read 0ppb.

                    I just sent an email to Gusmer asking to return the meter. We'll see what he says.

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                    • #25
                      Very interested to see how this pans out. Let us know what meter you ultimately decide on.

                      I haven't been impressed with Gusmer CS in the past either. That is why I assumed it was who you were dealing with. You could try talking to Hamilton directly to see if they will put in a new sensor, but at this point you are probably frustrated enough to just switch brands.

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                      • #26
                        Originally posted by UnFermentable View Post
                        Very interested to see how this pans out. Let us know what meter you ultimately decide on.

                        I haven't been impressed with Gusmer CS in the past either. That is why I assumed it was who you were dealing with. You could try talking to Hamilton directly to see if they will put in a new sensor, but at this point you are probably frustrated enough to just switch brands.
                        You read my mind. After we asked to return it, Gusmer offered to have their lab test it and either recalibrate or replace parts under warranty if needed. But at this point im thinking theres only a few different outcomes

                        1. We inadvertently and unknowingly broke the meter somehow
                        2. The meter is this innacurate and inconsistent out of box from the factory
                        3. We are somehow not calibrating it correctly despite following all instructions to a T and buying special high purity nitrogen (this is less likely since inconsistency arose as soon as we took it out of the box)
                        4. Gusmer shipped us an already malfunctioning meter (our rep said its never happened before)

                        No matter what the outcome, i just spent $7000 on this meter and i expect it to work well. When it doesnt and i have wasted my time i could otherwise spend running my business instead trying to diagnose this meter it makes me want to just be done with hamilton all together.

                        After our rep told us our problems dont warrant a refund and that we could send it in to have them look at it. I told him (as nice as possible) i understand there is a warranty but i would rather return it. He hasnt gotten back to me after several days.... keep in mind this meter is only about a month or two old. They seem to want me to keep this $7k paper weight.

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                        • #27
                          I feel your frustration.... If at all possible, try contacting Hamilton directly. Express your issues about the Gusmer CS and see if they'll help you out in any way (new meter, servicing, refund). I would also give them the heads up that a lot of people are out there buying these tools and you would be suggesting other brands and companies based on your experiences. Perhaps they will put a little pressure on Gusmer to do the right thing, or take care of it themselves.

                          My take, if you broke it without realizing it - probably not a tool you want hanging around in your brewery anyways. If you aren't calibrating it correctly after all that, then probably not a tool you can use practicably. After all the only thing worse than no data is incorrect data.

                          As stated previously, I have used the Beverly a few times with good trusty results. In fact I first trialed a machine within a day of an Anton Paar and had almost identical results. Your experience could be an isolated instance, or I may have gotten lucky on the ones I used (for relatively short periods of time). Orbisphere was fairly solid for me too, but doesn't offer the range of the Bev.

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                          • #28
                            Update, Still no response from Gusmer, our rep is ignoring me, and won't answer my calls. So if you are planning on buying a Beverly DO meter, don't plan on returning it.

                            another update, I called our water quality treatment plant to find out if for some reason they are oxygenating the source water before sending it out to the city pipes. (because of my high readings in the 25-30 ppm range which are theoretically impossible without pure oxygen.) anyways, I found out that they use an ozone treatment system and they regularly see low to mid 20 mg/l DO before they send the water out. So that answers my question about the odd high end readings we've been seeing. It still doesn't answer the question of the inaccuracy in the low range. It does somewhat restore my faith in beverly's high end accuracy, and tells us we need to reduce our wort oxygen rates.

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