Delta OHM HD45 17A, Manual

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Command
Value Length Description
Function: 10h 1 byte Parameters writing command
Data: 0000h to FFFFh 2 bytes First parameter address
0001h to 007Bh 2 bytes Number of parameters to be changed (N)
2 x N 1 byte Number of bytes
2 x N bytes New parameters values
Response
Value Length Description
Function: 10h 1 byte Parameters writing command
Data: 0000h to FFFFh 2 bytes First parameter address
0001h to 007Bh 2 bytes Number of changed parameters (N)
A parameter value is stored in a 16-bit register and always requires, therefore, a
2-byte length. The most significant byte precedes the least significant one.
Table 8.C (page 46) lists all available parameters with their register number.
The write function 10h changes only the value in the RAM memory; changes
are therefore deleted in case of power supply failure in the instrument. To
make any parameter changes permanent, “Parameter permanent storage” command
shall follow the parameter change (function 05h).
To change parameters protected by an access code, you must first write the code in
the configuration registers from number 10000 to 10005. After changing the
parameters, modify the content of the above mentioned registers to disable the code.
If the request involves entering a parameter not included in Table 8.C, the instrument
replies with the following error message:
Response
Value Length Description
Function: 90h 1 byte Error in parameters writing
Data: 02h 1 byte
Operation involved a non-existent
parameter (Tab. 8.F page 59)
Example:
Suppose you want to change CO
2
values corresponding to the initial and full scale
values:
• 0V or 4mA = 350 ppm
• 10V or 20mA = 1200 ppm.
The two parameters are protected by the access code “240471”.
In order to change the parameters, the access code has to be transmitted first by
means of the command below: