Remote control, Setup for remote control – JULABO FW95-SL Ultra-Low Refrigerated Circulators User Manual

Page 85

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HL, SL

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12. Remote control

12.1. Setup for remote control

9

6

5

1

SERIAL

1. Check the interface parameters for both interfaces (on the circulator and

PC) and make sure they match.
In the >Interface< menu, set the menu item >Type< to >RS232< or
>RS485<.

2. In the >Configuration< menu, set the menu item >Setpoint< to >RS232< or

>RS485<.

3. Connect both units with an interface cable.

Like all parameters that can be entered through the keypad, interface
parameters are stored in the memory even after the circulator is turned off.

12.2. Communication with a PC or a superordinated data system

If the circulator is put into remote control mode via the configuration level,
the VFD COMFORT-DISPLAY will read “R -OFF-” = REMOTE STOP. The
circulator is now operated via the computer.
In general, the computer (master) sends commands to the circulator
(slave). The circulator sends data (including error messages) only when the
computer sends a query.

In remote control mode, the start command and all values to be set must be
resent by the PC via the interface in case of a power interruption.
AUTOSTART is not possible.

A transfer sequence consists of:
• address (RS485 interface only)
• command
• space (⇔; Hex: 20)
• parameter (decimal separation with a period)
• end of file (↵; Hex: 0D)

• The response (data string) after an in command is always followed by a

line feed (LF, Hex: 0A).

The commands are divided into in or out commands.

in commands:

retrieve parameters

out commands: set parameters

Important times for a command transmission:

To ensure secure data transfer, the time gap between two commands
should be at least 250 ms.
The circulator automatically responds to an in command with a data string
followed by an LF (Line Feed). The next command should be sent only
after 10 ms.

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