User Guide

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Following are examples for setup item format:
• item C.32, maximum relay ON time: parameter value =
15, format = “+015◊◊“, where ◊ indicates a blank;
• item C.21, setpoint 2 value while in ORP mode: parameter
value = -1200 mV, format = “-01200”;
• item G.01, temperature compensation: parameter value
= “AtC”, format = “+0*AtC”.
For all items with a fixed set of choices, blank spaces on the
left of the value displayed are replaced with “*” (as many “*”
characters are needed to reach the maximum string length,
which is for example 3 for item C.57).
Blanks must be put on the tail for all items in order to have
always a total length of 6 characters (see the setup table).
The same parameter format used for setup item setting is
used also for setup item getting (i.e. when a
“NNGETCNN<CR>” command is received from the PC,
the reply “NN<STX>P
1
P
2
C
1
C
2
C
3
C
4
<ETX>” is sent back).
To perform a “NNSETCNN...” command the general pass-
word has to be sent in advance through the “NNPWD...”
command. See above for the password effectiveness time-out.
Some special setup items can not be set through RS485 com-
mands. In particular it is not possible to access any setup
item that performs a test on the instrument and it is not pos-
sible to configure the hardware identifier (setup item G.12).
Note No validity check of the sent item value is done upon recep-
tion of a “NNSETCNN<CR>” command: this check is done
by Hanna HI 92500 software.
The “NNSET...” and “NNGET...” commands when used for
password items, baud rate, hardware identifier, F.00 and F.10
items, P.00 through P.09 items, are answered with
“NN<CAN>”.
As soon as the process controller realizes that a command
has been received, it sends one of the following answers:
1) “NN”, ACK (char 0x06) if the process controller recog-
nizes the set command and performs the requested task;
2) “NN”, STX (char 0x02), DATA, ETX (char 0x03) if the re-