dodgy pH meter

[Rowyrow]

Hi all,
Im having a bit of a problem with one of my pH meters. I was calibrating them all befor a prac today and one of them is doing some weird stuff! when placed in the pH7 buffer it quickly goes to a pH -0.8 where all the other meters go to pH 7.1. does anyone have any idead whats going on and if there is something I can do to fix it? I have tried calibrating with pH 10 buffer and pH 4 buffer but all i get os a 0r on the screen. The model I have from EUROTECH instruments/ OAKTON instruments, they have only been used one beofr an i made sure I conditioned and calibrated them befor use. No problem was knowticed previously, (but ithas been a good siz onths since they where used). Any Ideas ?

[Rowyrow]

ok so after some research im gunn just guess that the probe is stuffed, by the looks of it the meter I have has replaceable probes so i will have to go looking for a replacement

[Ocean Breeze]

Havent heard of that one

Have you contacted the supplier?
Under warranty?
Complain and ask for a replacement unit?

I once callibrated one of mine with a mallet

It didnt play up at all after that

[RosalieM]

I would recommend going to the supplier and asking them. It does sound rather strange! Especially when the other ones are working fine. I assume they have all been kept under the same conditions so they can't argue environmental factors! Should be replaced under warranty if they are fairly new and only used once!

[Rowyrow]

That's the thing I don't know where they came from! They were ordered befor I started here last year ( by a teacher whos nolong working here) hmmmm
Lol

calibrated with a mallet

[RosalieM]

Check with your accounts department. They may be able to help you if you know approximate time frame.

[JelJane]

If you haven't already tried it I would suggest reconditioning the electrode and /or changing the batteries. Try googling Oakton pH meters - they have tech tips for problems with their pH meters etc..

[Rowyrow]

on further investigation it's not the actucal probe at al it is the unit itself. I switched the probes from one of the working ones and it's still not working, hmmm will have to track down a supplier.