GW Instek launches a new series of D.C. milliohm meter - GOM-804/805, which abundantly feature a 3.5-inch TFT display, maximum 50,000 counts measurement display, the rapid sampling rate of 60 readings per second, optimum 0.05% measurement precision, four-wire measurement method as well as the temperature measurement and temperature compensation measurement function to meet the requirement of low resistance measurement application. The GOM-805 also includes various drive modes and Dry circuit for contact resistance measurement applications. More features, including 20 sets of panel setting memory and much external control interface such as RS-232C, USB, Handler/Scan/EXT IO or GPIB (option), greatly elevate GOM-804/805 milliohm meter’s convenience on practical applications.
GOM-804/805 adopt a 3.5-inch color LCD to enhance the clarity of measurement results and to provide a display for related setting criteria that tremendously brings up the completeness of test information. Additionally, GOM-804/805, with the optimum 0.05% precision, augment the measurement speed to 60 sampling rate per second and maintain the display digits of five instead of four despite different speed selections. Furthermore, the independent functionality keys and direction keys together increase the operational convenience which allows users to complete their measurement tasks with intuitive convenience and speed.
GOM-805 provides Dry circuit and various drive modes (DC+, DC-, Pulsed, PWM) for measurement applications on different materials. The pulsed current output mode is suitable for interacting conductors of different materials and this output mode is to reduce the thermal EMF influence, which is caused by electric potential difference generated from different conductors acting on different temperatures while conducting low resistance measurements. The DC+ and DC- output modes are best for the measurement requirements of inductive components. The PWM output mode, ideal for changing temperature-sensitive materials, can avoid resistance value variation which is due to overload that happened on current measurement for a long period of time. During the DC+, DC- and Pulsed drive is supplied; the Dry circuit can work with them also. A dry circuit can limit the applied voltage under the open-circuit voltage of 20mV to avoid overvoltage occurred on both ends of components. The overvoltage will damage the oxide coating and the thin layer of the contact surface, as a result, the validity of measurement will then be ruined. For instance, the contact resistance of connector measurement is one of the applications.
With respect to connecting the external control, GOM-804/805 provides a D-sub 25-pin combined interface to execute, according to the functionalities, Handler, Scan, or EXT IO for respectively connecting to a sorting machine; connecting to an external on-off switch, and directly conducting external trigger control. For remote control and measurement result retrieval requirements, GOM-804/805 also provides various interface selections such as RS-232C, USB, and GPIB (GOM-804(option)/GOM-805(standard) interface. Furthermore, the control commands are compatible with that of GOM-802 that saves time in adjusting programs while switching from the old model to the new model.
To sum up, GOM-804 evolves from the GOM-802 platform with more advanced functionalities and specifications, including display digits, measurement speed, and standard interface (RS-232C/USB). With all the capabilities of GOM-804, GOM-805 augments itself with new measurement abilities (Dry circuit and various drive modes) to meet the requirements of broader low resistance measurement applications.