Hanna Instruments pHep Meter.

DuiNui

Anyone had any experience of this meter?
I was given one today and it seems to be total crap.
Periodic testing of the FT water has ranged from 6 to 8.9

I accept that it has probably never been calibrated since new, but one would expect a steady reading even if it was slightly out.

Also when you turn it on, it briefly says "16.6" then goes to the pH value.
What is the 16.6?
I was hoping it was temp, but it isn't.

http://www.hannainst.com/manuals/manHI_96107.pdf

RupertofOZ

Sounds like it needs to be calibrated....

Hanna usually makes pretty good gear....

Mr Damage

As you've suggested, if it was only out of calibration it should still settle on one reading, just the wrong reading.

If you are getting fluctuating readings then I would suggest the gel in the probe and/or the wick has dried out, or it could also need new batteries, which would then require a re-calibration afterwards.

Some hydro stores still re-gel meters, ring around and then take it in for the shop owner to have a look see... much better than getting a diagnosis over the interweb and throwing out a repairable meter.

As Rupe said, Hanna are generally good meters, but they still need looking after, ie: not letting the tip dry out. In saying that, don't fall for the "meter tip must always be stored in storage solution" furphy. I've sent a number of customers meters back for repair that have been stored in storage solutions.

I have a Eutech meter that is about 14 or 15yo now (1997 or 98 I bought it). I replaced the tip for the first time a couple of years ago and I've never stored it "storage solution". When in regular use, I just wash the tip under the tap after each use, don't dry any water off, then put the cap on tightly. Even when I stored it for a couple of years all I did was cut a little bit of material from an old flano shirt, double it over in the bottom of the cap, wet the material, put the lid on the meter, re-wet material every 3 months or so.

DuiNui

Ah ok thanks for that.
I didn't know they could dry out.
This one has been sat in a cupboard for at least 2 years, unused.
Batteries seem fine, so it's probably the wick.

Trying to think of the Thai for:
"Oi matey, my probe wick has dried out, can you fix it for me?"

RupertofOZ

To true Yabbies... could well be the gel...

Mr Damage

Quote:

Trying to think of the Thai for:
"Oi matey, my probe wick has dried out, can you fix it for me?"

Yeh... didn't look at your location... you may have a hard time finding a hydro store over there.

Quote:

To true Yabbies... could well be the gel...

Yep!... Unused for two years.. that'd be my bet!... especially with fluctuating readings.

DuiNui

If you went from a sample of pH 8 straight to a sample of 4, how long would you expect it to take to stabilise?
I've left it in a bowl of FT water for the day and it seems to have calmed down a bit, in fact if anything it seems to have fallen asleep, takes over 20 minutes when going from 4 to 8 and about a minute going from 8 to 4.

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