Emerson manual Discrete Output Blocks, Multiple Discrete Input Block, Rosemount 848L

Reference Manual

00809-0100-4696, Rev AA September 2004

Rosemount 848L

Simulation

DISCRETE OUTPUT BLOCKS

MULTIPLE DISCRETE INPUT BLOCK

MULTIPLE DISCRETE OUTPUT BLOCK

Simulation replaces the channel value coming from the transducer block for testing purposes.

The following procedure is used to simulate a DI output.

To change the output value place the Target Mode of the block to Manual and then change the OUT_D.VALUE to the desired value.

To simulate both the value and status do the following:

1.If the Simulate Switch is in the OFF position, move it to ON. If the Simulate switch is already in the ON position, you must move it to Off an place it back in to the ON position.

NOTE

As a safety measure, the switch must be reset every time power is interrupted to the device in order to enable SIMULATE. This prevents a device that is tested on the bench from getting installed in the process with SIMULATE still active.

2.To change both the OUT_D.VALUE and OUT_D.STATUS of the DI Block, set the TARGET MODE to AUTO.

3.Set SIMULATE_D.ENABLE_DISABLE to ‘Active’.

4.Enter the desired values for SIMULATE_D. SIMULATE_VALUE and

SIMULATE_D. SIMULATE_STATUS.

If errors occur when performing the above steps, be sure that the SIMULATE switch has been reset after powering up the device.

The digital output blocks are used to receive a value from another device to be used to either drive a contact output or to use in the logic equations. The DO blocks make their values available to the 848L by placing the value in a variable called DO (n) where n=1 to 8. Like the DI block, all eight outputs can be communicated in a packed format by selecting the appropriate channel number. The DO block does not drive the outputs directly but sets the state of the internal variables DO(n). To drive an output from the DO block, the DO(n) variable is placed in one of the output equations.

OUT1_EQ = DO(1);

The MDI block allows 8 values with their status in one block with 8 individual outputs. The 8 values are selected by one of the “Array” channel numbers.

The MDO block allows 8 output values with their status in one block with 8 individual inputs. The 8 values are selected by the “Array Outputs” channel number.

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