Although DMMs often use unshielded test leads, such connection schemes are generally inadequate for low level measurements made with picoammeters, electrometers, and SMUs.

• 虽然数字多用表常常使用无屏蔽的测试引线，但是这种连接方式在使用皮安计、静电计和SMU等进行低电平测量时一般是不合适的。