1、钳形电流表基本结构及使用时该注意的问题基本结构钳形电流表的结构实际上是一个交流电流互感器，相当于一次绕组的匝数极少，二次绕组的匝数很多的变压器，二次负载为一个交流电流表。当钳形电流表夹入一相交流电线时，就等于有了一次绕组。此时工作电流就在钳形电流表铁芯回路感应磁通，该磁通穿过二次绕组感应二次电压，并在二次负载中形成电流。这个二次电流的大小和一次电流成正比，这样表头指示的数值就可以间接的反应一次工作回路电流的大小，所以它不需要断开电路来心儿凉电流。使用钳形电流表应注意的问题选择合适的量程档，防止小量程档测大电流而将表针打坏。不要在测量过程中切换量程档。因为钳形表二次绕组匝数很多，测量时工作在相当
2、于二次短路状态，一旦在测量中切换量程，会造成瞬间二次开路，这是会在二次绕组中感应很高的电压，这个高电压有可能将绕组的层间或匝间绝缘击穿。在测量三相交流电流时，夹住一相线读书为本相线电流。夹两根相线读书为第三相的线电流值。夹三根相线时，如果三相平衡，读书应为零，若有读书，表示三相电流不平衡。如果被测交流电流较小，读书不明显，可以采取在卡口中多绕几匝再测。此时，测得的读书必须除以所绕的匝数才是电路实际的电流值。The attention on ammeter basic structure and useBasic structureStructure of pincer amperemeter
3、is actually an AC current transformer, the number of turns of the equivalent of a winding rarely, two number of turns of the secondary winding of the transformer is many, two load as an AC current meter. When the clamp ammeters with a phase AC line, equivalent to having a primary winding. The curren
4、t work on the clamp ammeters core loop induction flux, the flux through the two secondary winding induction voltage two times, and two times the load current is formed in the. The two times the size of the current and a current that is proportional to, this header indicating numerical can indirect r
5、esponse to a loop current, so it does not need to disconnect the circuit to the heart cold current.Use should pay attention to the problem on ammeterSelect the range shift right, prevent small range profile measuring big current and the needle broken.Dont switch during the measurement range. Because
6、 the clamp meter two winding number many, when measured in the equivalent of two times the short-circuit state, once the switch in the measurement range, will cause flash two times open, this is on the two windings of induction voltage is high, the high voltage may be layer or turn winding insulatio
7、n breakdown.In the measurement of three-phase alternating current, holding a book for the phase current phase. Two phase reading for the clamped three-phase line current value. Clamp three phase lines, if the three-phase equilibrium, reading should be zero, if the reading, said three-phase current unbalance.If the measured AC current is smaller, reading is not obvious, can be taken in the bayonets of around a few more turns retest. At this time, the measured current reading must turns around is divided by the actual value of the circuit.
