Bio-Rad CHEF Mapper® XA System - Manual (Page 61)

Section 11
Troubleshooting Guide
Problem Solution
Equipment:
No power 1. Check fuses at back of power module
2. Check source of A/C power
3. Contact Bio-Rad Laboratories
No voltage across electrodes, 1 Check that lid is on
with AC power light lit on 2. Check that serial cable is fully inserted at
power module both ends
3. Check that coiled interlock cable is firmly
attached
4. Confirm that all leads are properly attached
5. Check HV fuse on front panel (0.5 A FB) and
replace if necessary
6. Check that a programmed voltage gradient is not
set at 0
7. Check that unit is not set in pause mode
Gel floats away 1. Pump flow rate is too high or too low. Adjust
with Variable Speed Pump
No or low buffer flow 1. Look for kink in tubing
2. Check Cooling Module; buffer in the heat
exchanger can freeze if the chiller is cooling, but
the pump is not on
Gel band patterns appear very 1. Foreign object in chamber; remove
distorted; lanes very curved,*
thermometer, gel stops at top of gel, etc.
bands sharp, but slanting 2. Insufficient or non-uniform cooling due to low
pump flow
3. Check that buffer is level with surface of gel;
use leveling feet
4. Check that field vectors add up to a net forward
migration
5. Replace damaged electrode
6. Buffer volume should be 2.2 L for models
purchased after 1994.
7. Power module fault; contact Bio-Rad
Laboratories
*Slight distortion of the outermost lane is normal
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