Alarm - Omega RD2800 Series User Manual

11. OTHER PROGRAMMING
Alarm parameters (alarm types, alarm value, etc.) can be programmed for each alarm point (channel, level). By
programming the alarm parameters, alarm activation can be displayed and also the activation and reset can be
printed. See Section 10.3. Press
Alarm output is an option. The alarm outputs for "FAiL (failure) " and "C. End (chart paper end)" are available in
addition to measured values.
1
Alarm Parameters
The default is no alarm programmed.
1) Alarm points (Channel, level)
Alarm point can be programmed up to level 4 for
each channel. "FAiL" and "C. End" can be
programmed instead of the channels.
FAiL...Alarm when
servo-circuit/mechanism is abnormal
In this condition, the status lamp is not lit.
C. End...Alarm at just before when the chart paper
ends.
2) Alarm types
10 different alarm types can be selected for each
alarm point.
: High alarm
Absolute
: High alarm with
value
standby
Rate-of-
: Increase limit
change
: Differential high

alarm

Differential
: Differential high
alarm with standby
3) Alarm value
Value for alarm activation
2
Alarm Types
The high alarm for the absolute value activates when the measured value equals to or is higher than the alarm
value. The low alarm activates when the measured value equals to or is lower than the alarm value.
For the rate-of-change alarm and the differential alarm, refer to the followings.
Rate-of-change alarm
Increase limit alarm: Change width (PV2 to PV1) per unit
time (∆t) is plus.
Decrease limit alarm: Change width (PV2 to PV1) per unit
time (∆t) is minus.
＋
U
0
Change width
△t
(PV2 to PV1)
D
－
High alarm Low alarm
Unit time (∆t) = Measuring interval (about 0.1 sec.) x
Measuring count (1 to 20)
* Do not apply a "minus" symbol to the alarm value of the
decrease limit alarm ().
and 8 simultaneously to display the [Alarm] programming screen.
SHIFT
ALARM
the hardware except
: Low alarm
: Low alarm with
standby
: Decrease limit
: Differential low
alarm
: Differential low
alarm with standby
 alarm value
 alarm value*
－６３－
11.5 Alarm
4) Others
Rate-of-change alarm: Program measuring
Differential alarm: Program channels to be
compared.
Relations between alarm
parameters and alarm activation
Absolute value alarm
1 1
1 2
Alarm
H
L
specifications
0 0
50
35
0
(55)
(1) The above figure shows programming alarm
point up to level 4 on CH 1.
(2) Alarm is in active at level 2 (high alarm) as the
measured value (55) is higher than the alarm
value (50).
*No alarm output is provided to the standard
specifications and the relay No. is fixed to "0". Refer
to Section 12.2 for the programming of relay No.
Alarm with standby
This is the function not to activate an alarm until
the alarm becomes in reset condition, even if the
alarm is in active condition. This function is only
available when the power supply is turned on.
When changing parameters, this function is only
available by reprogramming it after clearing once.
Differential alarm
(Differential high alarm)
Alarm
value
Difference of measured
value (absolute value)
Alarm activation
Difference of measured value (absolute value) equals to or
is higher than alarm value: Differential high alarm activation
Difference of measured value (absolute value) equals to or
is lower than alarm value: Differential low alarm activation
count (1 to 20)
1 1
Channel
Alarm
points
4
3
Level
H
H
Alarm type
0 0
(Relay No.)*
70
60
Alarm value
100
Measured value
(Differential low alarm)
Difference of measured
value (absolute value)
Alarm
value
Alarm activation