Troubleshooting
“Er 1” Display
The 3M Electronic Pipettor - 5mL has a
1.Allow the pipettor to charge on the stand for a minimum of 15 minutes.
2.Press 
to clear the error message.
The display should now show the Power “ON” reading. If the error message remains displayed, consult your 3M representative for additional assistance.
Bubbles
The appearance of many small bubbles on the Petrifilm plate may indicate that the dispense speed is too fast. Lower the dispense speed (see Speed Selection page 20).
In more viscous samples, a single large bubble may form if the tip is allowed to contact the sample surface during dispensing. To prevent this, position the tip at least 5mm above the surface during dispensing.
“Frozen” Display
If this display is shown and the pipettor
will not operate, thehas been pressed.
1.Press 
twice to clear the display and continue working.
See Speed Selection, page 20.
Page 11 of 15 - June 2001
Troubleshooting
Liquid in Tip Cone
If liquid is aspirated beyond the tip cone filter, clean the tip cone as follows.
1.Switch the unit “OFF”.
2.Remove the tip ejector collar: hold down the tip ejector lever and twist off the tip ejector collar.
3.Unscrew the tip cone from the control handle. Do not rest the pipettor
on the lab bench. Do not touch the stainless steel piston with any foreign objects to avoid scratching or contamination.
4.Use ethanol and a soft
5.Apply a thin layer of grease to the piston seal.
NOTE: Use only the piston grease specifically recommended by your 3M representative. Other types of grease can permanently damage the piston.
6.Reassemble the unit and perform a calibration check.
piston
tip
ejector tip cone collar
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