User's Guide _______________________________________________________________________
118 __________________________________________________________________ M211107EN-C
The system asks the following:
UPDATE CONFIGURATION PARAMETERS
UNIT ID (2 CHAR) ( 1)
If the PWD32 unit is named by one or two character ID codes, the
OPEN
and polling commands use it as a parameter. The ID code is also included
in the data message heading. ID 1 is used as a default in the message
heading, if no other ID is given. The current ID can be removed by
pressing the hyphen ( - ) as an answer to the question.
In multidrop configuration, where several sensors are on the same
communication line, the units are differentiated by the ID.
The next
CONF
parameters are hardware or system dependent. They can
be changed from the factory set values for better performance or
maintenance purposes. The example configuration session is explained in
the following.
The currently measured
offset
value (not a parameter) is shown in
brackets.
OFFSET ( 136.86)
Y
OFFSET REFERENCE UPDATED
After receiving the Y answer, the system accepts the offset frequency to
be the reference parameter for hardware monitoring. The parameter value
is further compared with the current value to detect drift or other failure
in the optical signal measurement electronics.
The Alarm limits function of PWD32 is not used in the FS11P
configuration.
Backscatter/contamination control is done by comparing the current
values of backscatter signal with the reference values given with the
CLEAN
command. The limits given here are limits for the change in
backscatter signals.
TRANSMITTER CONTAMINATION LIMITS
WARNING LIMIT ( 1.0)
1.5
WARNING LIMIT UPDATED
ALARM LIMIT ( 5.0)
The transmitter values are in volts (V). The measurement range is 0 ... 13
V, where 0 V is a blocked lens. The limit value is given as a positive
value although the signal becomes smaller when contamination increases.
A contamination change of 5 V represents about a 10% decrease in the
transmitter's lens transmittance (and also a 10% increase in visibility
indication).
Содержание FS11P
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