Siemens S5-135U/155U Test Mode Enabling the Test Mode with the 923A, 923A Coordinator, Test mode

Models: S5-135U/155U

1 560
Download 560 pages 1.68 Kb
Page 276
Image 276

Multiprocessor Operation/Coordinators

Test Mode

!

Enabling the Test Mode with the 923A

Warning

Since, in the test mode, no CPU can emit a BASP (output inhibit) in the event of a fault, the test mode must be switched to the inactive state without fail after completion of startup to avoid a critical or even hazardous system state.

Before you can go into the test mode with the TEST switch, you have to enable it on the module. This is achieved differently with the 923A and 923C coordinators.

Insert jumper 3 - 14 on coding socket EP 45 as shown in the following sketch.

16

14

9

EP 45

 

923A Coordinator

 

 

1

3

8

Enabling the Test Mode with the 923C

Set DIL switch S1.3 from Off to On (the following table shows the DIL switches as delivered; see also Figure 6-2).

Reaction of the CPUs

DIL S.

S1.1

S1.2

S1.3

S1.4

S1.5

S1.6

on

off

x x

x x

x x

Effect

±

±

Test mode

No. of occupied CPU slots = 2 No. of occupied CPU slots = 3 No. of occupied CPU slots = 4

When the coordinator mode switch is set from STOP to TEST, the CPUs can be started individually. There is therefore no synchronized transition to cyclic program processing. The output of signal BASP is suppressed on all CPUs, even if there is an error.

f an error occurs with a CPU switched to RUN, only this one goes to the Stop state in the test mode. The error is indicated by slow flashing of the CPU's STOP LED. The error at this CPU does not affect other CPUs.

If the test mode is not activated, a changeover from STOP to TEST does not result in any reaction of the CPUs.

6-14

System Manual

C79000-G8576-C199-06

Page 276
Image 276
Siemens S5-135U/155U Test Mode Enabling the Test Mode with the 923A, 923A Coordinator, Reaction of the CPUs, Test mode