ANSALDO VME-SSI AVMESSI

输入模块的滤波可以降低输入信号的线间的差模干扰。为了降低输入信号与大地间的共模干扰，PLC控制器要良好接地。输入端有感性负载时，对于交流输入信号，可在负载两端并接电容和电阻，对于直流输入信号可并接续流二极管。为了抑制输入信号线间的寄生电容、与其他线间的寄生电容或耦合所产生的感应电动势，可采用RC浪涌吸收器。

输出为交流感性负载，可在负载两端并联RC浪涌吸收器；若为直流负载，可并联续流二极管，也要尽可能靠近负载。对于开关量输出的场合，可以采用浪涌吸收器或晶闸管输出模块。另外，采用输出点串接中间继电器或光电耦合措施，可防止PLC控制器输出点直接接入电气控制回路，在电气上完全隔离。

The second task is to identify all points in the loop that might be attached to earth ground. Devices like PLCs and power supplies frequently attach the connections to earth ground. Some sensors, like thermocouples, might not be electrically isolated and cause an unintended earth point.

Having more than one earth point in the loop will cause the loop to malfunction because current can flow between the earth points instead of through the wires.The third task is to pick the cable. There are many existing solutions supplied by cable manufacturers. We recommend a twisted pair cable of at least #22 AWG.The exact cable a particular installation will require will depend on the environment the cable is run through and the length of the cable. This document contains general advice and is not meant as a formal engineering solution to any particular application.
A 4/20mA signal can represent anything, but the values that the loop represents are always defined by the transmitter (or transducer) in the loop. The range of the transmitter identifies the values being transmitted at 4mA and at 20mA.Obtain the range of the transmitter and you will know what to set the display(s) to. Sometimes a transmitter sends a signal related to but not a direct measure of the desired quantity.

GEDS200SLCCG1AEE
GEIC660ELB912
GEIC660ELB912
GEIC660ELB912
GEDS200ADPBG1ABB
GE531X307LTBAJG1
GE531X307LTBAJG1
GE531X307LTBAHG1
GEDS6800CCIE1F1D
GE531X304IBDAMG1
GE531X304IBDAMG1
GE531X303MCPBBG1
GE531X303MCPBBG1
GER-TPD3
GESBI-PDP-32
GEVMIVME-7807
GEVMIVME-7807
GEVMIVME-7807
GE511-0101-08B
GEUR6CH
GEUR6CH