New pH probe--help!!

[guypettigrew]

One of these has just arrived.

It's come with a small bottle with crystals in and a syringe with a hypodermic needle attached. If you look closely at the photo on ebay you'll see there's a circular hole in the blue collar at the top of the probe. I've tried sticking the needle through it without success. I'm guessing the little bottle with crystals is probe storage and top up stuff and needs to have water added.

The instruction leaflet is all in Chinese, so is of no help!

Any one got any idea what I'm supposed to do, please?

Thanks.

Guy

[Eric]

A pH probe is usually stored in a near saturated solution of potassium chloride and suggest in your case the water has evaporated to leave those crystals.
Potassium chloride solution is also that inside the probe and as you correctly assume, is topped when necessary using the syringe through that hole. The ring with the hole is rotatable and when turned will align with another for filling and taking readings. When the probe is not in use the ring should be turned to ensure no leakage. I presume you have a supply of storage solution.

[guypettigrew]

Thanks Eric

It seemed likely the collar should move, but it wouldn't budge when I tried moving it by hand.

However, it's amazing what can be achieved with expert help, advice and a pair of long nosed pliers!

The collar now rotates freely and the probe and the little bottle it screws into are now full of storage solution. As you guessed, I have plenty!

Thanks again.

Guy

[Kev888]

Thanks from me too, Eric. I have one on order from the same seller, so that is helpful. There isn't actually any problem with my original but it is so old (by what seem to be normal standards) that I can't expect it to go on forever.

Somewhat annoying if the storage solution is not/no-longer a solution though. I'm not really sure how bad that is for the probe, but presumably it cannot be ideal or there'd be no point in using the storage solution normally.

[Eric]

Assuming both probes are similar to the one I bought some time since, the storage holder is very small and will soon dry if it not properly tightened or there is spillage. I would hope and expect after a good soak in storage solution the probe should be fine.

My replacement has lasted much longer than the original and after a good rinse in DI water needs no more than a slight touch to calibrate.

[Kev888]

Thanks again; doesn't sound too unreasonable then. Especially for less than six pounds; last I looked the official replacements were over thirty pounds, so I shall hardly quibble.

Lately I've been getting a lot of disappointment from chinese ebay sellers, but at this price differential it really has to be tried!

[guypettigrew]

And it arrived in about 10 days. Amazing!

I'll have a go at calibrating it tomorrow. Hopefully it'll be as good as Eric's.

Guy

[guypettigrew]

What a wonderful probe! Just a couple of times round the pH 4 and 7 buffers and it was calibrated and rock solid in the reading. Also takes well under a minute to stabilise the reading.

Thanks for the recommendation, Orlando. Much appreciated.

Next brew won't be for a month or so, so it'll be interesting to see how well the probe has held the calibration.

Guy

[orlando]

Thanks for the recommendation, Orlando. Much appreciated.

Funnily enough after doing so I had a brew in which my meter was not registering a stable reading so I decided to order a new on too. Like Kev says at that price it really has to be tried. It's claimed to have been dispatched but the delivery window is 9th Dec - 10th Jan. Better not be the latter.

[guypettigrew]

Just checked. Mine took 12 days to arrive. From China--pretty good!

Guy

[private4587]

Gentlemen could i please ask how this probe is used, I noticed that it has a BNC connection on the end where does this plug into and does it come with usage instructions please excuse my ignorance

[Kev888]

I think most of us use them with a Voltcraft pH meter:

the probes are replaceable and connect to the meter via the BNC connector.

There may be other meters that the probes would work with, but the voltcraft is the only one I'm familiar with. Unfortunately they have 'really' shot up in price since many of us bought them so not sure how long they'll remain popular.

[Jocky]

I think most of us use them with a Voltcraft pH meter:

the probes are replaceable and connect to the meter via the BNC connector.

There may be other meters that the probes would work with, but the voltcraft is the only one I'm familiar with. Unfortunately they have 'really' shot up in price since many of us bought them so not sure how long they'll remain popular.

REALLY shot up in price.

I bought mine in June 2015 for £40.80 delivered.

Now I can't find one under £90.

[orlando]

I think most of us use them with a Voltcraft pH meter:

the probes are replaceable and connect to the meter via the BNC connector.

There may be other meters that the probes would work with, but the voltcraft is the only one I'm familiar with. Unfortunately they have 'really' shot up in price since many of us bought them so not sure how long they'll remain popular.

REALLY shot up in price.

I bought mine in June 2015 for £40.80 delivered.

Now I can't find one under £90.

I blame home brewers.

[LeeH]

￡19.53 | BEVERAGE DOCTOR - PEN STYLE DIGITAL PH METER HOME BREW without battery
https://s.click.aliexpress.com/e/DLcSmDnZt

These seem popular if anybody is after a new meter.


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