Vaisala Drycap DMT152, Руководство пользователя

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Syntax Description
The following example shows that a high limit alarm has been enabled for channel 1. If the
measured value rises above the -40.00 °C T
d
limit, analog channel 1 is set to 5 V (Limit Hi = -40.00,
Level Hi = 5.00). The malfunction alarm ( aerr ) is disabled for both channels.
Note that the term quantity in the serial interface corresponds to measurement parameter .
alarm ?
Channel 1:
Low Limit : OFF
High Limit : ON
Aerr : OFF
Quantity : Tdf
Limit Lo : 0.00
Limit Hi : -40.00
Hysteresis : 0.00
Level Lo : 0.00
Level Hi : 5.00
Channel 2:
Low Limit : OFF
High Limit : OFF
Aerr : OFF
Quantity : ppm
Limit Lo : 0.00
Limit Hi : 0.00
Hysteresis : 0.00
Level Lo : 0.00
Level Hi : 0.00
Avoid enabling more than one alarm type for a channel.
5.3.2 Purge Status Alarm
The transmitter can temporarily freeze the output when measurement is not possible (for
example, during sensor purge). The purge status alarm indicates this state by setting the
analog output at a defined level, in the same way as the limit alarm (see Limit Alarm
(page 36) ).
Use the STATUS command to enable/disable the alarm and to define the voltage/current levels
(see example below). The channel is set to the value of Level Hi when sensor purge is active
and to Level Lo during normal operation. During auto-calibration, the output is not frozen, that
is, the output of the purge status alarm is on Level Lo .
Chapter 5 – Serial Line Operation
37