Chapter 13 : fail – safe system, Chapter 13: fail – safe system – Horner APG QX651 OCS User Manual
Page 71

MAN0798-04-EN
CH.
13
August 20, 2009
Page 71 of 95
ECN # 979
CHAPTER 13: FAIL – SAFE SYSTEM
13.1 Overview
The Fail-Safe System is a set of features that allow an application to continue running in the event of
certain types of "soft" failures. These "soft" failures include:
• Battery power loss
• Battery-Backed Register RAM or Application Flash corruption due to, for example, an excessive
EMI event.
The Fail-Safe System has the following capabilities:
• Manually backup the current Battery-Backed RAM Register Settings into Flash memory.
• Manually restore Register Settings from the values previously backed up in Flash to Battery-
Backed RAM.
• Detect corrupted Register Settings at power-up and then automatically restore them from Flash.
• Detect corrupted or empty application in Flash memory at power-up and then automatically load
the AUTOLOAD.PGM application file from Removable Media (Compact Flash or MicroSD).
•
If an automatic Register Restore or Application Load occurs, the OCS can automatically be
placed in RUN mode
The fail-safe system can be accessed by going to the system menu of the controller. A new menu “Fail-
Safe System” has been added at the end of the main system menu for this. Selecting “Fail-Safe System”
menu will open the following menu screen:
Figure 13-1 – Fail–Safe System Menu