I don't know quite where to post this question, and it doesn't at this time require a call to Tech Services.
I was looking at the ELTS installed in the theater, and I noticed that there was a 9V battery on the Control Panel.
I could not find a reference to it in the manual.
What is its purpose?
Does it need to be changed regularly?
The preventive maintenance section of the manual does not have a schedule for replacement. The troubleshooting section doesn't mention it.
Honestly, the ELTS was installed 15 years ago. I am just glad that the batteries in both of the ELTS are not leaking.
Thanks,
John