Vaisala DMT152 - Limit Alarm

User's Guide _______________________________________________________________________
38 ___________________________________________________________________ M210865EN-H
where
c1
=
Channel 1 analog output mode. Available options are:
1 = 0 ... 20 mA
2 = 4 ... 20 mA
4 = 0 ... 5 V
5 = 0 ... 10 V
7 = I alarm (ON/OFF output using current)
8 = U alarm (ON/OFF output using voltage)
Modes 1 ...5 are normal measurement
modes, where
malfunction alarm is always enabled, and limit alarm and
purge status alarm
are disabled.
c2
=
Channel 2 analog output mode. Available options are:
1 = 0 ... 20 mA
2 = 4 ... 20 mA
4 = 0 ... 5 V
5 = 0 ... 10 V
6 = LED alarm
7 = I alarm
(ON/OFF output using current)
8 = U alarm (ON/OFF output using voltage)
Enable mode 6 for channel 2 i
f you are using the Vaisala
LED cable.
Example:
amode 2 1
Ch1 output : 4 ... 20 mA
Ch2 output : 0 ... 20 mA
Limit Alarm
The limit alarm is activated when the measured quantity goes below the
low limit or above the high limit. The alarm can be specified during
ordering for a specified parameter, or configured on the serial line using
the ALARM command.
When ordering a limit alarm, the alarm levels are set as follows:
- For current output, an active alarm is indicated by the current being
at the maximum of the scale (20 mA).
- For voltage output, an active alarm is indicated by the voltage being
at the maximum of the selected scale. For example, if the voltage
output scale is 0 … 5 V, an output of 5 V indicates the alarm is active.
Using the ALARM command, you can also set a hysteresis value to
prevent the repeated triggering of the alarm when the measurement
fluctuates around a limit value.
ALARM<cr>