TEC-B-01 User Manual
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version 1.1
page 25
8. Trouble Shooting
In the following section some common problems, possible reasons and their solutions are described.
Important
: Please note that the suggestions for solving the problems are only hints and may not work.
In a complex setup it is impossible to analyze problems without knowing details. In case of trouble
always contact an experienced electrophysiologist in your laboratory if possible and connect a cell
model to see whether the problem occurring with electrodes and “real” cells persists with the cell
model.
Problem 1:
After immersing an electrode into the bath there is an unusual high potential offset.
Possible reasons:
1.
The Ag-AgCl coating of the silver wire in the electrode holder is damaged
2.
The Ag-AgCl pellet or Ag-AgCl coating of the silver wire in the agar-bridge are damaged
3.
There is an unwanted GND-bridge e.g. caused by a leaky bath
4.
The headstage or the amplifier has an error
Solutions:
1.
Chloride the silver wire again
2.
Exchange the pellet or chloride the silver wire in the agar-bridge
3.
Try to find the GND-bridge and disconnect it e.g. by sealing the bath
4.
Contact npi
Problem 2:
Even if no stimulus is given a current flows through the current electrode
Possible reason:
1.
The BIAS current is not adjusted
Solution:
1.
Adjust the BIAS current according the procedure described in chapter 0
Problem 3:
The system oscillates (see also
voltage clamp
in chapter 5.5)
Possible reason:
1.
The capacitance of the electrode is overcompensated
2.
There is too much series resistance compensation
Solution:
1.
Turn the CAPACITY COMPENSATION potentiometer (#
13
) to the most left position and
compensate the input capacitance again
2.
Turn the SERIES RESISTANCE COMPENSATION potentiometer (#
3
) to a lower value
Problem 4:
With the cell model connected the R
EL
display does not show the correct value (within a tolerance of
2%).
Possible reason:
1.
The headstage has an error
Solution:
1.
Contact npi
