Connection Of A Relay Box; General Description; Command List Of The Sample Changer - Xylem TW 7450 Operating Manual

4 Connection of a relay box

4.1

General description

The TW 7450 sample changer has a 9-pin plug connection for connecting pump and valve modules. Via this I/O
connection, the devices available for this purpose can be (e.g. further MP 25 or a peristaltic pump) by means of
an accessory cable. The I/O connection is controlled by the Titration Software TitriSoft. There are 4 outputs
available. The necessary commands can be taken from the command list (see 5 Command list of the sample
changer).

5 Command list of the sample changer

The TW 7450 sample changer has a number of commands with which it can be controlled from a PC. These
commands are automatically generated by TitriSoft. If you want to create your own application programs, the
commands listed below must be used.
The sample changer has no address and is connected directly to the PC via USB or the RS-232 cable supplied.
The sample changer is controlled with the following RS parameters.
Command Action
The TW 7450 moves to the position with the coordinates x and y and lowers the head by
the mm specified in parameter z. The x and y coordinates are specified in 0.1 mm steps,
abs = x-y-z
the z coordinate in 1 mm steps. The head moves up automatically before moving to a new
position.
getpos Returns the current position x-y-z in 0.01 mm units
absz=z Lower the head by z mm in 0.01 mm units. The head can be lowered by max. 166 mm.
up Lifting the head
fc_sol=1 Switch on the diaphragm pump connected to connection 7 (see Figure 6)
fc_sol=0 Switch off the diaphragm pump connected to connection 7 (see Figure 6)
stiron Switching on the rod stirrer
stiroff Switching off the rod stirrer
Setting a stirring speed in x % in 1 % steps. The rod stirrer is not automatically switched on
stirsp=x
with this command.
Baudrate 9600
Parity No
Start bits 8
Stop bits 1
31