Jobo ATL2 + temperature adjustment?

Hi All, I have had a Jobo Autolab ATL2 plus for a few months now but have noticed that the temperature probe that is in the first chemical bottle gives a high reading by one degree centigrade....i.e. If the chemistry is 20 deg the probe says it's 21 deg.

This may not seem on the face of it to be a major problem until you go to do a second run and the machine won't start because it says the chemicals are over temperature by a degree and of coarse it will never cool to 20 deg (which is really 19 deg) because the water jacket will keep it at 20 deg.

Is there any adjustment on the control board to tweek the temperature back to being correct?

Both the water in the bath and in the chemical bottle were checked with an accurate digital thermometer and were both 20 deg so the error is with the machine.

Thanks in advance for any tips....Cheers Dave

Hi Dave: If the problem persists and no useful suggestiong obtains, then consider emailing or calling Greg Blank at Omega-Satter. The company services Jobo equipment here in the USA, and Greg might be able to give you a useful hint, or refer you to someone in the UK and "vicinity" who can help.

http://www.omegasatter.com/

Ed

Mahler_one said:

Hi Dave: If the problem persists and no useful suggestiong obtains, then consider emailing or calling Greg Blank at Omega-Satter. The company services Jobo equipment here in the USA, and Greg might be able to give you a useful hint, or refer you to someone in the UK and "vicinity" who can help.

http://www.omegasatter.com/

Ed

Click to expand...

Obviously Greg is either too busy or not interested as he hasn't responded to my PM

I have ordered the service manual off eBay.

Cheers Dave

Having got the service manual on a cd rom...It is simple.

Remove the two philips screws and the allen bolt holding the cover below the display, removing the grommet at the right hand side through which the proble lead goes.

On the right of the exposed pcb is silkscreened WA (water jacket) and CHE (chemical) with push on plugs. On the thin wire from the probe is a black variable resistor. Remove the end cap to reveal a slotted trimmer.

The manual says set a program to 32 degrees C and allow the machine to heat up to this temperature.....With an accurate digital thermometer measure the chemical temp to check it is 32 deg and then adjust the pot so that 32 is displayed when the chemical temp button is pressed.

Job done. Cheers Dave

Jobo Calibration Procedure

Here's the link to Jobo's calibration document.

They're on-line, just hard to find.

http://www.jobo.com/jobo_service_analog/us_analog/bulletins/b017.htm

-Pat