Watlow Series 922 - Manual (Page 66)

66 WATLOW Series 922 User's Manual
Alarms
How To Use The Alarms , Chapter 7
Figure 37 -
Alarm Limits for
Alarms 1 and 2 with
"Deviation" Type
Alarm (ALTYP=D,
ALTYP=D)
NOTE: Only Chan-
nel 1 is shown here.
Temp
SP1
Actual
0
°
C
Time
AL 2
AL 1
AH 2
AH 1
New SP1
A1L
A1H
Time
Alarm Function, Latching or Non-Latching
Alarm function is either "latching" or "non-latching." Latching is a means of
"saving" indication of an alarm event for the operator to clear manually. A
latching alarm requires the operator to manually clear it with the ENTER key
when ACTUAL returns to within the limits. A non-latching alarm clears itself
automatically when ACTUAL returns to within the limits. It's your choice.
Here again is the "LAT" information from the Operating Parameters:
LAT Defines Alarm Function:
NLAT = Non-latching. Alarm relays are automatically energized when
ACTUAL temperature returns to within the operating band (as defined
by ALTYP X, AXL and AXH).
LAT = Latching. Requires the ENTER key to manually energize alarm
relays after ACTUAL temperature returns to within the operating band
(as defined by ALTYP X, AXL and AXH).
To clear an alarm in the RUN mode, simply press ENTER. To clear an alarm
in the HOLD mode, return to the SYSTEM prompt. Press the MODE key until
CLR ALRM is displayed and press ENTER.