Keysight Technologies B1500A Self-Paced Training Manual page 108

Module 3
Low Current Measurement
You can check whether the ASU connection is correct or wrong. Open the Configuration window
and look at the ASU tab screen.
If the ASU Serial Number field shows its serial number, the HRSMU-ASU combination is correct.
If the ASU Serial Number field shows *s/n mismatch, the combination is wrong.
The B1500A can work with this wrong combination however it cannot satisfy its specifications. The
specifications are guaranteed for the correct combination of HRSMU and ASU.
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