Outputs Of The I/O Port; The "Pump-Unit" Port; Connection To A Computerized Titration System; Interface Connections - SCHOTT TW alpha plus Mode D'emploi

5.4 Outputs of the I/O port

The outputs of the I/O port are configured as follows:
Output
1
2
3
4
Common emitter
Common power supply
The supply voltage for the optocoupler outputs has to be made from an external source and amounts to be-
tween 1 and + 18 V. Max. output current of the HCPL-0700 optocoupler module: 60 mA.

5.5 The "Pump-Unit" port

This port, located on the back panel the device, is used to control a connected pump (e.g. of the no. TP 20
type) or valve. The built in relay is able to control a voltage of 220 V and a current of 2 A. The <aaCE> com-
mand will switch the port on, the <aaCA> will switch it off again. The <aaCS1..9> command will switch the port
on for the specified time, with the number indicating the time in terms of seconds.

6 Connection to a computerized titration system

6.1 Interface connections

The TW alpha plus Titration Sample Changer is equipped with two serial interfaces (RS-232-C) for data com-
munication with other devices. The plug connectors for these interfaces are located on the back panel of the
device (fig. 1, items 7 and 8). The upper socket establishes the connection towards a computer, whereas the
lower socket connects to other devices.
The transfer parameters can be set using the "Baud Rate" switch (fig. 1, item 5).

6.2 Integration in a daisy-chain

Using a device address will enable you to operate more than one titration devices in the form of a daisy-chain.
To do so, use an RS-232-C cable to connect the computer with the first device in the chain (e.g. with a
TITRONIC ® 110 plus Piston Burette). Using another cable, connect the second RS-232-C interface of the
burette to the upper RS-232-C interface (1) of the TW alpha plus Titration Sample Changer. From the second
(lower) RS-232-C interface (2) of the TW alpha plus Titration Sample Changer, it is possible to connect addi-
tional devices (fig. 1, items 7 and 8).
Please make sure that the devices in the chain have different addresses assigned. The device address of the
TW alpha plus Titration Sample Changer can be set on the back panel of the device. The address range is
from 00 to 15, depending on the 0 to F switch position.
Please note: When using the device with a TitroLine alpha plus Titrator, the sample changer must always be
connected directly downstream of the titrator.
In this case the RS interface 2 of the TitroLine alpha plus Titrator is to be set to the 8; 1; no parameter record.
Pin number
9
10
11
12
14 and 15
13