Instruction Manual

748213-S April 2002

Model 755R

2-6 REMOTE RANGE CHANGE OPTION

The power supply circuitry on the Remote Range Board 646004 must be jumpered for the correct line voltage, either 115 VAC or 230 VAC. See Drawings # 656081 (Table 2) and 646090 for correct jumper locations.

On the Remote Range Board, an additional option exists: for using either the on-board 12 V to drive the range select relays or an external 12 V supply.

To use an external supply:

1.Remove the E to F jumper (DWG 646090).

2.Apply the external 12 V to J3-5.

3.Program the remote controller to pull the range bits, J3-1 through J3-4, low. (See Table 2-1 below.)

To use the internal 12 V supply:

1.Verify the E to F jumper is in place.

2.Connect the controller's common to J3-6 to reference the instrument's common to the controller's common.

NOTE

DO NOT connect anything to J3-5.

3.Connect J3-1 to J3-4, as shown in the truth table below, to switch ranges.

Remember that you are dealing with inverse logic and not normal binary addresses. Also, this process switches the recorder output only, and does not affect the front panel dis- play.

 

 

J3-4

J3-3

J3-2

J3-1

 

Hex

Range 1

 

1

1

1

0

 

E

 

 

 

 

 

 

 

 

Range 2

 

1

1

0

1

 

D

 

 

 

 

 

 

 

 

Range 3

 

1

0

1

1

 

B

 

 

 

 

 

 

 

 

Range 4

 

0

1

1

1

 

7

 

 

 

 

 

 

 

Note: 1 = 12 V, 0 << 1 V.

 

 

 

 

 

Table 2-1.

Remote Range Switching Truth Table

 

2-12

Installation

Rosemount Analytical Inc. A Division of Emerson Process Management