Abnormal artifact caused by TC02 perfusion heater

I've been using a 60 electrode MEA to record from mice retinas. It has been working properly in the lab for more than 3 years. This afternoon, out of nowhere, the TC02 system started producing an extremely strong artifact. It is a combination of a very noisy baseline with a very regular spiking behavior. It disappears when the heater power is turned off or the cable unplugged from the power supply. Has anyone had this experience? Not sure what I should do, please help.

Dear Kmawad,

most likely the heating element has no good contact to the ground. Especially with upright amplifiers it can happen, that due to the finishing of the amplifier housing or some spillage the screws holding the heating element from the lower side of the amplifiers do not have proper electrical contact to the housing. Try to remove one or two of the screws an clean and scratch the thread and the screw.

If the situation does not improve by this, please send us screenshots of the noiselevel observed with the TC02 on and connected, off and connected and disconnected to meyer@multichannelsystems.com.

Greetings

Thomas

Thanks for your prompt reply. I came in this morning and set up the rig again to verify that the artifact remained but it was no longer present. I went ahead and regrounded the PH01 anyway.

Unfortunately, I have a new problem. The TC02 base unit largely overshoots the "set point" for temperature. It consistently goes at least 10 C over its target (30. and I am forced to shut it off, though the temperature is still rising. Channel 1, which controls the base heating unit overshoots its set point (30. but remains stable at a temp of ~35.4 C. Channel 2 (which controls the PH01)increases termperatures much more rapidly and constantly. The highest temperature I've recorded is 41.8 C before shutting it off though it was still rising. This behavior was noticed yesterday but not mentioned as it seemed likely that the creation of the artifact was throwing the heater off. It's now more likely that the PH01 is creating an extreme temperature environment (something of that sort) and this somehow leads to the creation of the artifact. Any thoughts on why this would be happening? Thanks in advance for your help.

PS: I tried unplugging and replugging all of the cables as well as the power cord to the TC02 main unit. None of that helps.

Von:
MCS Support Team <otrs@multichannelsystems.com>
An:
Kareem Mawad <mawadk@msnotes.wustl.edu>
Betreff:
Re: Abnormal artifact caused by TC02 perfusion heater
Erstellt:
07.08.2007 16:29:00
Anlage:
TC01-02_Manual.pdf Herunterladen 408.6 KBytes
Dear Dr. Mawad,

please check, if your channels are configured for the correct instruments. The

parameters are optimized for our various products, which have to be defined
accordingly.

I attach our TC02 Manual describing how this channel configurations setting
are done.

Of course you can also manually adjust the parameters.

Greetings

Thomas

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Dr. Thomas Meyer
Multi Channel Systems MCS GmbH
Aspenhaustrasse 21
72770 Reutlingen
Germany
Tel: +49-7121-90925-42
Fax: +49-7121-90925-11
http://www.multichannelsystems.com
Amtsgericht Tübingen, HRB 2616

Innovations in Electrophysiology

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