Making Measurements    2
Agilent U1251A/U1252A User’s and Service Guide 128
Alerts and Warning During Measurement 
Overload Alert
The meter provides an overload alert for voltage measurement 
in both auto and manual range modes. The meter beeps 
periodically once the measuring voltage exceeds 1010 V. For 
your safety, please be aware of this alert.
Input Warning
The meter sounds an alert beep when the test lead is 
inserted into the A input terminal but the rotary switch is 
not set to the corresponding mA.A location. The primary 
display indicates a flashing “A- Err” until the test lead is 
removed from the A input terminal. See Figure 15.
Figure 15 Input terminal warning
For your safety, look out for this alert. When you are alerted, 
immediately remove the test leads from the measuring source.