MODEL 54e pH/ORP

SECTION 5.0

 

SOFTWARE CONFIGURATION

5.7 CHANGING ALARM PARAMETERS (continued)

Interval Timer Setup

Timer: Disable

Timer: Time activated

Interval: 24.0 hr

ExitEdit

Repeats: 1

On time: 120 sec

Off time: 1 sec

ExitEdit

On time: 120 sec

Off time: 1 sec

Recovery: 600 sec

ExitEdit

7.

Menu Item

Options

 

 

 

 

Timer (enable)

Disable/AL1/AL2/AL3

 

 

 

 

Interval

0-999.9 hr

 

 

 

 

Repeats

1-60

 

 

 

 

On time

1-2999 sec

 

 

 

 

Off time

0-2999 sec

 

 

 

 

Recovery

0-999 sec

 

 

 

The Interval Timer is used to automate a relay closure sequence based on a time interval. See Figure 5-2 for examples. The original controller configuration disables the timer, so the first step in using the timer is to select an alarm relay (1, 2, or 3), which will enable the feature. All parameters can be adjusted by highlighting the desired item and pressing the Edit 4 key. Once Edit has been pressed, change the item as needed and then press Save 4 to store the value.

NOTE

The alarm relay selected for Interval Timer cannot be used for other purposes such as a process or tempera- ture alarm. While a timer sequence is occurring, both current outputs will be placed in hold (even if hold was not enabled in Section 5.6) and the other 2 alarms will be placed in their default states.

"Interval" determines how often the timer sequence will run. When set to 24 hours, the sequence will run daily.

"Repeats" is the number of times the relay will activate during the sequence.

"On time" is the number of seconds the relay will stay closed (on) during each repeat.

"Off time" is the number of seconds the relay will stay open (off) between each repeat.

"Recovery" is a waiting period after the activation sequence that allows sensor readings to return to normal before outputs and alarm relays are taken out of the hold/default states.

For more on the Interval Timer, see Section 6.0, Theory of Operation.

NOTE

The timer can be used for periodic chemical or mechan- ical cleaning of a coated sensor. If high reference imped- ance is used to initiate the timer cycle, the reference impedance set point in Section 5.8 is used.

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Emerson 54e pH/ORP instruction manual Timer Disable, On time 120 sec, Recovery 600 sec