Grounding and Isolation of Sensitive Measurement Equipment for Arc Flash Testing at High-Power Laboratory

Report on High Energy Arcing Fault Experiments: Experimental Results from Medium Voltage Electrical Enclosures

“…This data acquisition system was used for the NIST plate thermometer and Tcap instruments and is described in the literature [6,13]. Data acquisition systems for use in arc flash measurements have also been described in the literature by others [34]. The NIST data acquisition system was improved for Phase 2 by incorporating non-multiplexed data acquisition, so that each data channel has a dedicated analog to digital converter in addition to a dedicated isolation transformer.…”

Galvanic isolation circuit for measuring systems operating in environments with strong electromagnetic disturbances

“…Modern galvanic isolation circuits use magnetic fields [1], electrical fields and light [5,6] to transmit signals through the isolation barrier [2]. Galvanic isolation for analogue signal (GI1 and GI2 on fig.…”

“…Modern measuring systems often have to work in environments with strong electromagnetic disturbance. The result of this are additional measurement errors, increased risk of damage to devices and risk of equipment damage and danger of electric shock to human personnel [1]. There are a few ways, in which interferences may occur in measuring systems: direct galvanic connection, capacitive coupling, magnetic coupling and electromagnetic radiation.…”

“…Usage of galvanic isolation breaks the loop of common ground connecting each point of the measuring system with different potentials [3]. Therefore, we have some beneficial effects: currents flowing in the common ground wires, which are the source of interference, are terminated; common mode voltage and the risk of electric shock are reduced [1]. Figure 1 represents a simplified block diagram of a measuring system containing: sensor S, signal conditioning systems SCS, acquisition systems ADC, digital processing DSP and display D. Galvanic isolation GI marked with a dotted line may be introduced in many points of a measuring system, between ground points GND with different potentials.…”