Rosemount 54E, Инструкция по эксплуатации

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MODEL 54e pH/ORP SECTION 6.0
THEORY OF OPERATION
6.8 CONTROLLER MODE PRIORITY
Your Model 54e pH/ORP can function in different modes
depending on both how it is configured, what process
conditions exist, and actions an operator may have made.
To reconcile these possible modes, there is a set priority
that determines exactly what will happen to the 2 current
outputs and the 4 alarm relays in the event of multiple
modes occurring at the same time. See Table 6-1 below. Priority is in the following order (from lowest to highest):
normal, fault, timer, hold, feed limit, test. Each output or
relay acts as if it is only in the state of highest priority.
NOTE
Some of these features may not be in use for your con-
troller.
TABLE 6-1. Controller Mode Priority Chart
1
Indicates the state IF that item has been configured or selected (i.e. if it is an interval timer or a feed limit
timer or it is the one being tested). Unconfigured or unselected items are not affected by that mode.
Condition Definitions:
1. Normal refers to conditions when no other mode is present.
2. Fault is when the instrument has diagnosed a fault condition.
A fault message is displayed and the red LED will be on.
3. Interval Timer is only while the timer sequence is occurring.
4. Hold Mode is while hold is activated by the operator (i.e. during calibration).
5. Feed Limit occurs when a feed limit timer has reached it's limit and is turned off after being on for too long.
6. Simulate tests are described in Section 5.4.
Action Definitions:
1. Normal is determined by process conditions or how the item has been configured (Sections 5.5, 5.6)
2. Open is a deenergized alarm relay. (alarm off)
3. Default is the setting configured for each item if there is a fault. (Sections 5.5, 5.6)
4. Closed is an energized alarm relay. (alarm on)
5. Hold is the setting for the current output configured in Section 5.5 (this could be a fixed mA value or the last
normal value)
6. Prior is the state the alarm had before that mode occurred.
7. Test is the value input by the operator (mA for current, on or off for a relay).
Condition Priority Current Current Alarm Alarm Alarm Alarm
Output 1 Output 2 Relay 1 Relay 2 Relay 3 Relay 4
Normal 1 Normal Normal Normal Normal Normal Open
Fault 2 Default Default Default Default Default Closed
Interval Timer 3 Hold Hold Default/ Default/ Default/ Prior
Normal
1
Normal
1
Normal
1
Hold Mode 4 Hold Hold
Default Default Default Prior
Feed Limit 5 Normal Normal Open
1
Open
1
Open
1
Closed
Simulate tests 6 Test
1
Test
1
Test
1
Test
1
Test
1
Test
1