Emerson OCX 8800 instruction manual Method 2, for Load Resistance 250 Ohms, Out

Instruction Manual

IM-106-880, Rev 1.0 January 2007

OCX 8800

Method 2, for Load Resistance < 250 Ohms

Refer to Figure 5-2 and the following steps to connect the HART communicator to a signal line with less than 250 ohms load resistance.

Do not make connections to the HART communicator's serial port, 4-20 mA signal lines, or NiCad recharger jack in an explosive atmosphere. Explosions can result in death or serious injury.

1.At a convenient point, break the oxygen analog output 4-20 mA signal line and install the optional 250 ohm load resistor.

2.Plug the load resistor into the loop connectors (located on the rear panel of the HART communicator).

Figure 5-2. Signal Line Connections,

< 250 Ohms Load Resistance

4-20 mA Terminal Block in

Electronics Housing

	1
A OUT	1 +
A OUT	1 -

RL <250Ω

O2 4-20 mA Signal Line

Analog Output Device

Loop

Connectors

HART Communicator

Rear Panel

250 OHM

Load Resistor

(See Note)

HART

Communicator

Model 275/375

NOTE: The signal loop must be broken to insert the optional 250 ohm load resistor.

37390021

5-3