RayTek LineScanner MP150, Руководство по протоколу

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Dedicated Commands
30
Rev. B4 Aug 2019
MP150 Protocol
b) Ok we change the order. Let the list be: PM4, VF0 (512, 90°) and the scanner is at the moment
configured to 45°, 256. Now the scanner would answer with a NAK after PM4 and we run into
the same problem.
The problem becomes even more complicate because the FQ command is in this set of dependencies
too.
As conclusion it was
decided to let the scanner accept the “wrong” command in the hope that the
correction will follow up.
The dependencies must be checked by the programmer.
5.10 Response and Exposure Time
The response time of the scanner can be calculated with: 1 / scanFre 20 ms.
The
exposure time is given by: 1 / scanFrequency.
So, at 150 Hz a signal has to have at least 7 ms to be recognized and it can take up to 27 ms to have this
signal at an analog output.
5.11 Ambient Temperature Compensation
The ambient radiation gets reflected from the object with the factor 1-emissivity. In the standard
temperature calculation, the background temperature is assumed to be equal to the internal temperature
of the scanner.
The more the background temperature differs from the internal temperature and the lower the
emissivity of the object the higher the error will be that the reflected ambient radiation takes into the
measurement.
To correct this, influence the background temperature can be given to the scanner. Two ways are
available:
•
A fixed background temperature can be set with the commands:
AC1
A<ambientTemperature>
•
The background temperature can be given as a voltage using the commands:
AC2
AL<bottomRange>
AH<topRange>
5.12 Customer Adjustment
The customer adjustment is a last option to adapt the temperature reading to the customers process.
The first option is, the standard parameters to achieve this are: emissivity, window transmissivity and
background temperature.
Please use the customer adjustment only if these parameters should not lead you to
correct temperatures .
Caution: the customer adjustment is calculated on the “temperature side” of the internal calculation.
This means it changes if you change the emissivity.