The analog output function code writes seven analog outputs to an analog output module. Two blocks of this type may be linked together to utilize all 14 channels on the analog output module. When these function blocks are linked, only the status output of the primary block will be functional.
The analog output function block has eight outputs. The first seven are the calculated output values in percent. The eighth output is the status of the I/O module.
The control system must be carefully evaluated to establish default values that will prevent personal injury and/or property damage in case of module failure.
Address of the analog output module.
Block address of the next analog output block. The first block in the list is the control module block. The second block is the I/O module.
Can be set to allow the module to continue to operate if there is an analog output module problem.
0 = trip control module
1 = continue to operate
S4 through S10
Block addresses of the outputs N through N+6.
S11 through S17
Define the default state of outputs N through N+6.
0 = -6.25 percent
1 = 106.25 percent
2 = hold
When power is supplied to the analog output module, the outputs are at zero percent. The default states defined by S11 through S17 are active after the multi-function controller completes initialization in execute mode. Initialization is complete when the green LED on the I/O module is on. The outputs will now enter the configured default state when a loss of the bus clock is detected. The outputs are held in their current state upon entry to configure mode.
S18 through S31
Define the low limit (EU zero) and range (EU span) of outputs N through N+6.
Output Percent = <Output> - EU Zero x 100.0
Figure 149-1 shows two analog output blocks linked together to utilize all 14 channels on an analog output module.