Emerson 308014EN Manuel D’Utilisation

Rosemount Tank Radar REX
Chapter 11 Electrical Installation of the 

308014EN, Edition 4

May 2013

The RTG 3900 is equipped with two cable outputs for intrinsically safe 
and non-intrinsically safe connections. Wires are clearly marked with 
numbers and designation of wires is shown on a printed plate at the 
cable outputs. The transmitter can also be equipped with an integrated 
junction box (JBi).

W11 is for the non-intrinsically safe power supply, the TRL/2 Bus and 
relays. The power supply and the TRL/2 Bus can be connected via an 
external junction box, or directly to the transmitter if it is equipped with 
the Integrated Junction Box. See 

information on how to use the different Junction Boxes. An external 
junction box can either be customer supplied or supplied by Emerson 
Process Management/Rosemount Tank Gauging as an option. 

Wires in the cable output that are not used must be properly insulated 
and terminated in the junction box.

W12 is for the intrinsically safe connection of Data Acquisition Unit 
(DAU), Display Panel RDU40, analog inputs and temperature sensors. 
There are two versions of the W12 cabling: 8 or 15 wires. The 15 wire 
version is used when temperature sensors are connected to the 
transmitter.

TH3900_T

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