Pearson 70 Manuale Utente

Installing the Scanner

A dedicated isolated/insulated ground for the OpScan iNSIGHT 70 system must 

be provided. If possible, route a dedicated ground conductor between the main 

power panel and the OpScan iNSIGHT 70 system branch circuit (with the 

dedicated feeder). If a dedicated ground conductor is not feasible, then another 

code-approved method must be used. (The isolated ground conductor is noted in 

the National Electrical Code, Section 250-74, Exception 4.) Use of an isolated 

ground rod or grounding to a water pipe is not acceptable.

An isolated/insulated ground conductor, equal to or larger in size than the 

heaviest gauge AC feeder conductor in the circuit, should be bonded to the 

ground bus in the building main power panel. Route it with the circuit conductors 

in the wiring conduit. Pass this ground through any intermediate panel boards 

without connection to the panel board grounding terminal bars. The National 

Electric Code, cited above, allows for the installation at the intermediate panel 

board of an isolated ground bus, constructed from a terminal block kit, for the 

interconnection of the isolated ground conductor.

This isolated/insulated ground conductor runs as a single, uninterrupted circuit 

between the building main power panel and the OpScan iNSIGHT 70 system 

branch power panel. It forms the interconnection point for the third-wire grounds 

of all OpScan iNSIGHT 70 system components. Connect all OpScan iNSIGHT 70 

system component third-wire grounds to this ground; do not connect any 

equipment other than OpScan iNSIGHT 70 system components to this ground 

conductor. This condition is met if all system components are plugged into the 

switched convenience outlet in the base of the scanner.

At some sites, local regulations require that all installed equipment be connected to 

a system common ground. In this case, connect all OpScan iNSIGHT 70 system 
components to the common ground at only one point. Connect third-wire grounds of 

system components into a common bus connected to the common ground at a single point.

Make sure the equipment third-wire ground (green wire) does not become 

connected to the conduit at the outlet box or connector. To avoid an inadvertent connection, 
use a NEMA 5-20R type isolated-ground receptacle such as a Hubble IG-5362.

When installing the OpScan iNSIGHT 70 system in a multi-story building, 

provide a low noise ground by connecting the isolated ground of the system to 

the structural steel of the building. Install the isolated ground system as described 

above. In addition, bond one end of a heavy gauge wire or copper braid to the 

isolated ground bus in the branch circuit panel serving the OpScan iNSIGHT 70 

system. Weld the other end of this wire or braid to the nearest vertical steel 

structural member. Do not substitute a water pipe or an isolated ground rod for 

the vertical steel member.

With circuit power turned off, the resistance between the circuit neutral 

conductor and the isolated ground conductor must be less than 2.1 ohms.