Truncheon styled CF meter Maintenance & Callibration

[Shithappens]

I had the chance to test my grow-safe cf meter the other day against both another grow-safe cf and a standard truncheon only to find they all read differently

 

My Grow-safe meter read 30 in test solution

 

My mates Grow-safe meter read 32 in same

 

And the truncheon read 25

 

Now ok the contacts had been cleaned with a new tooth brush and scrubbed pritty well!

 

The advice i got from the shop i bought it from was to get some emery paper and give them a scrape or with a stanely knife blade!!!!

 

That sounds a bit full on and wondered why the hell i didn't ask in here first before bothering to ask at the shop

 

What do yous use to clean these styled CF meters??? Has anyone ever callibrated these meters and if so which pot inside is the calibration one?

[Luke Skywalker]

If it's a truncheon style meter with no calibration dial/screw then you can usually get them back to working order by the following cleaning....

 

Rinse off the probe well, and using one finger put some unscented Jif, (it has to be unscented too, don't get lemon jif or apple jif, just plain old Jif creme cleanser) in a dollop on the probe tip. Rub your finger around the surface and you'll soon see the deposits of salts and dirt come off in the jif as it changes colour.

 

Don't do it too long, maybe a minute.

 

Then using the same finger, rinse off all the jif under water. Don't touch the probe with any other finger than the one you used to clean it with, or you'll just be contaminating it again.

 

Then you can test it against a cf calibration solution and you should see a marked improvement. If it's a particularly old one, you might find you have to repeat the process, but it's usually a once only thing.

 

Don't use a scourer or toothbrush or anything else, (my god, a knife? sheesh...) to clean the probe head. You could seriously damage it.

 

Try looking at getbluelab.com for a more detailed instruction on cleaning a truncheon, which will apply to all those which use similar, (ripped off) technology.

 

Keep in mind that not all probes are created equal. Bluelab truncheons come with a 5 year warranty for a reason.... Others are usually 1 year or less.

[Shithappens]

Cheers man getting all of them together in a few days and will retest them to see the result.

 

Allways wondered why if i ran the same as hes truncheon why mine would burn like hell....

 

So everyone that follows guide lines of other people please check your testers as you may well be reading differently

[Luke Skywalker]

Keep in mind that all growrooms are different, and all environments affect nutrient and water uptake in various ways. Unless your room is identical in makeup as the other persons, and you have exactly the same house within the same microclimate of your suburb, then you're going to have differences.

 

When it comes down to it, I'd rather spend the extra $ to have a meter I know will work and work accurately.

[pipeman]

actually Luke when you think about it the idea behind your 1st and 2nd paragraphs contradict each other.

[Luke Skywalker]

? What's so incongruous between these two ideas? - "I think Bluelab is better at making truncheons than other brands and they're more accurate" , and - "there are differences between all growrooms, no two are identical, so don't assume your nute values will be the same..."

 

Just because I use a truncheon, doesn't mean I'm using someone elses instructions or EC values.... It's a much more powerful and valuable tool than that pipe... I was more making a comment about the quality and accuracy of most other brands than inferring that I follow rigid guidelines and need the accuracy on the truncheon to do so...

 

Was that what you were trying to say?

[pipeman]

it depends how you define quality. As long as a meter is consistent, there is no great advantage in it being accurate.

[Luke Skywalker]

Well that depends on if it's consistently out one way or another. If it's consistently telling you you have no salts in water when you really have say .4 ec there, then it could be quite harmful. And there's no way to tell when you do get rid of that amount because you can't measure negative EC. And if it tells you you have more salt in the water than you actually have you could underdose it under the misapprehension that you'll harm the plants at the strength it indicates is in solution... Any meter that reads out of it's calibration isn't going to always read exactly that far out of range. That isn't how EC meters work.... They drift with repeated use and contamination, and this doesn't take into account that it may be a poor quality probe or meter, which would further compound the drift and inaccuracy over time. Pretty quickly you'll get a meter which reads 29 in 27.6mS solution, and then 32, then 34 etc... They can under-read as well, particularly with the lesser units. It's amazing how little care some people take with these instruments, and then wonder why they're having troubles with their growing.

 

And consistency and accuracy pretty much go hand in hand with scientific instrumentation like this. If something is consistently inacurrate, it's pretty useless... It's only useful if you know how inaccurate it is and if that inaccuracy is consistent, (which in this case it wouldn't be....) and if something is inconsistently accurate, it's useless too... You'll never know.... so the two are intertwined to my mind.

[Shithappens]

Just wishing to clear some things up the grow-safe meters i have are now absorbed by bluelabs and where made using the same system as the truncheon as a royalty payment system from bluelabs.

 

the truncheon has just another way of displaying the value and of course is in a tube not a box with wires to the sensor.

 

The growsafe meters which now sell under the bluelab maestro label are running standalone and are exactly the same still as i was told that mine will plug directly into the maestro system.

 

we did a basic test mixed some more water in our test sample and it did read the same swing out we did forgot to test straight water as that would have been interesting...as the truncheon should have been forced into a negative reading !!!! and they should have an error code for that

 

My meter one such grow safe does read 1 cf on basic tap water which i assume is correct so i wuld say the truncheon is clogged up and the other meter could be out??

 

haha actually we dont really know which one is which as neither was marked before we brang them together and both being stoned at the end we just gave up and grabbed one

 

I have the gif non scented and am just waiting for him to bring hes around for a final testing..

 

If it's consistently telling you you have no salts in water when you really have say .4 ec there, then it could be quite harmful. And there's no way to tell when you do get rid of that amount because you can't measure negative EC. And if it tells you you have more salt in the water than you actually have you could underdose it under the misapprehension that you'll harm the plants at the strength it indicates is in solution

I dont really care about the accuracy as i have never followed peoples recomended CF amounts as that has burnt plants for me and I have learnt to watch my plants instead which i see as better so now i know what they want. The meter is just for me when i fill my tanks (As long as it is x amount out at top of range and x amount out at bottom of range)

 

PS does anyone know of a source of the bluelabs ph meter probe for the maestro.. as my mate got given a full system to try (thus the second CF meter) and get working but the probe has been in a box for a while dry

[Taipan]

PS does anyone know of a source of the bluelabs ph meter probe for the maestro.. as my mate got given a full system to try (thus the second CF meter) and get working but the probe has been in a box for a while dry

 

They are a standard pH probe with BC connection. Pretty sure Nutriflo at West Gosford would have one. They used to. Before buying a new one, try soaking the probe in some 4 buffer overnight. It may come alive again.