请问如何才能使34980A停止缩放？

我正在为工厂设置编写测试程序。
我的程序的用户将测试威廉希尔官方网站 板的各种电压和电阻。
我的程序当前向用户显示：A。测试点所在的位置（图片），B。可接受的限制（高，低）和C. 34980A的当前读数。
然而，在某些测试点上，34980A似乎可以缩放值，在低值和高值之间跳转。
如何使34980A停止缩放？
如果将其设置为手动模式将有助于我知道。谢谢！



     以下为原文

  I am writing a test program for a factory setting.  The user of my program will be testing circuit boards for various voltages and resistances.  My program currently shows the user: A. Where the test point is located (picture), B. The limits (high,low) of what is acceptable and C. The current reading of the 34980A.  On some test points however the 34980A seems to scale the values, jumping between a low value and a high value.  How can I make the 34980A stop scaling?  If setting it to manual mode would help let me know.

Thanks!