Module B882-032 24Vdc Diagnostic Output, Quick Start Test

Quick Start Test Table

This test configures the module as follows: B882 (bi-directional).

The quick-start test is presented in the following table.

Step	Procedure
1	Set the 4 position dip-switch as follows: (viewing the rear of the module when held vertically): SW1 and SW2 Left Not Used (keep to left SW3 Right Selects B882 (bi-directional) SW4 Left Not Used (keep to left)
2	Determine which channel and slot location is being used for this module.
3	Wire terminals 5,15, 25, 35 to a +24 Vdc supply, and wire terminals 6,16, 26, 36 to a -24 Vdc Supply on a AS -8535 -000 high density connector.

NOTE: Remove the keying tabs on the AS-8535-000 high density connector prior to installing the module.

Quick-start test table, continued.

Step	Procedure
4	Stop the PLC.
5	I/O map the module as a B882, registers 30001/30002, 40001/40002 binary.
6	Start the PLC.
7	Write FFFF (hex) into registers 40001 and 40002.

NOTE: Ensure that no field devices are connected to these points.

Quick-start test, continued.

Step	Procedure
8	Active light should now be blinking.
9	Look at registers 30001 and 30002 in binary format, all bits should be set to a one indicating a returned fault. The fault is present as a result of the open-load condition of the outputs. The module is correctly monitoring its output points and is being read properly by the controller.

NOTE: Active blinking = One or more outputs have sensed a load fault. Active on steady = Points have the minimum load requirements.

Application Example

The B882 module, with ability to sense its own output points is an excellent choice for critical operations. The example shown below shows ladder logic that allows for detection of point errors. This could ultimately be used to control a system if a critical failure occurred.

The block move shown below moves the contents of registers30001 and 30002 into 40008 and 40009 where they can be worked. The XOR Block Exclusively OR’s the contents of 40001 and 40002 with 40008 and 40009, then places the results of this XOR in 40008 and40009. This gives a value that can be used in the compare block that compares the contents of 40001 and 40002 to the values in 40008 and 40009. When a miscompare occurs, coil 00001 turns on, which can be tied to an indicator light, or safety circuity for system protection.

The following illustration provides an example of the application diagram