GE GFK-0787B user manual Auto Test

6

Auto Test	Highlight this item then press the space bar key to display a screen for
	setting up Input Autotest and Test Type for individual circuits (screen for
	16-circuit blocks shown here).

If input circuits on the blocks in the group should be autotested, circuit 16 (the powerfeed output) must have autotest enabled. If no circuits are to be autotested, circuit 16 can have autotest disabled, and input devices can be wired directly to the power source instead of being wired to circuit 16 (the powerfeed output).

By default, each circuit is set up for autotesting, as shown by the X next to the circuit number. To turn off autotesting, select that circuit (click on the circuit or select it using the cursor keys). Press the space bar to remove the X. Note: For all unused circuits on the blocks, autotest should be set to off. Also, it is possible for an input block to include I/O circuits that are not part of the GMR system, and which are not to be autotested. Be sure to turn autotest off for non-GMR circuits.

Test Type: Select whether the testing should be Synchronous (the default) or asynchronous.

Asynchronous Autotesting: allows the input autotest to continue executing on other blocks in a group which are not affected by the fault. It can be selected if:

A.redundant discrete input devices are used (the power feed outputs of each block ARE NOT wired together).

B.non-redundant simplex discrete input devices are used with isolation between blocks.

Synchronous Autotesting: synchronous input autotesting must be selected if non±redundant simplex discrete input devices are used without isolation between blocks (I.E. the power feed outputs of each block ARE wired together). With Synchronous Autotest, Loss of Block faults or certain autotest faults may prevent the autotest from continuing to execute for that input block group and thus cause a I/O shutdown for the inputs in the group. See page 4-18 for more information.

GFK-0787B Chapter 6 Configuration 6-29