Most switch mainframes can be triggered externally via the trigger input and can send an output trigger pulse when the relay contacts have settled.
大多数开关主机都可通过触发输入进行外部触发，并且在继电器触点稳定之后可输出一个触发脉冲。
2
If the load resistor was connected directly across the voltmeter input terminals, the current through the relay contacts would cause a voltage drop and the measured cell voltage would be in error.