HF scientific CLX Online Residual Chlorine Monitor - Manual (Page 28)

CLX (1/12) Page 23
REV 5.1
8.0 Additional Features and Options
8.1 Backlit LCD
The backlit LCD allows for easier readability of the LCD display in low light or no light
conditions. The backlight is intended for continuous operation. The brightness is
adjustable from a menu in the CONFIG mode.
8.2 RS-485 Outputs
The CLX has the capability to operate in three different RS-485 modes. Included is a
mode for interfacing into the HF Online software package (section 8.2.1 below), a simple
communication mode and Modbus communications. All modes will automatically
configure and do not require any changes or selections
8.2.1 HF Online (HF catalog # 19783)
The CLX can operate as a small SCADA system with an optional PC software
package, called HF ONLINE. This system allows for an interface with a
combination of Micro TOL’s or CLX’s, totaling up to 255 units, for the purpose of
data logging. This system will interface directly with common database and
spreadsheet software.
8.2.2 Simple Communication
The CLX can provide basic communications over simple programs such as the
Hilgraeve HyperTerminal that is included with most Microsoft Windows
packages. The user could also use Visual Basic or other programs. The factory
setting communication parameters are 8 bits, no parity and 1 stop bit. These can be
changed in the Extended CONFIG menus 7.10 RS-485 Parameters.
The master computer will send out:
•
Byte #1 the attention character “:” in ASCII or 3A Hex
•
Byte #2 the address of the CLX being queried
•
Byte #3 & 4 CR LF or 0D 0A in hex
The CLX will respond with:
•
The same attention character “:” in ASCII or 3A Hex
•
The address of the CLX
•
The Reading
•
The Unit (mg/L)
A sample communication would look like this:
(Master computer requesting a report from address #1) :1 CRLF
(CLX set to address #1 Response) :001 0.0249mg/L