ABB AnalyzeIT ZMT Series Instrucciones de uso complementarias - Página 14

Navegue en línea o descargue pdf Instrucciones de uso complementarias para Instrumentos de medida ABB AnalyzeIT ZMT Series. ABB AnalyzeIT ZMT Series 20 páginas. Zirconia oxygen analyzer systems

Imprimir página

OPERATION

Before attempting any serial communication, first ensure that

the ZMT Analyzers connected to the computer terminal or host

computer by serial link are functioning correctly as individual

instruments. This is achieved by connecting all analog inputs,

applying the input signals and checking that the digital display

reads appropriately.

Ensure that the serial data connections to ZMT Analyzers

have been made correctly with respect to the computer

terminal, or host computer, interface. If the above check

appears satisfactory, test the serial communication by sending

an appropriate message from the compcorrectly correctly uter

terminal or host computer to a transmitter and observe if it

replies; thus establishing communication. If communication is

not established, check that the computer terminal, or host

computer, interface is correctly set up and that the plug-in

links within each transmitter are positioned correctly

– see Section 5.

Check that the parameters programmed in the instrument's

Serial Data Communication Page

the computer terminal or host computer – see Section 7.

If communication is still not possible or is erratic, check that the

computer terminal, or host computer, interface has pull-up and

pull-down resistors connected as shown in Figs. 9.1

Note. If no reply is received from the instrument within

160ms, retransmit the command. If after five command re-

entries, a satisfactory reply has not been received, the

communication link has been broken and must be

rechecked.

are compatible with those of

Computer Terminal or Host Computer

Pull-down

Tx-

Resistor

Tx+

Rx-

Rx+

Pull-down

Resistor

Fig. 9.1 Pull-up and Pull-down Resistors

10 SPECIFICATION

As detailed in the Operating Instructions (IM/ZMT), with the

following additions:

EIA Communication

Standards

4-wire mode

Parity

Odd

Even

Block check character

Transmission line length 1200m max.

Transmission speeds

2400 baud

4800 baud

9600 baud

+5V

Pull-up

Resistor

'A'

'B'

+5V

Pull-up

Resistor

'A'

'B'

RS422, RS485

None

Programmable

Programmable on or off

1200 baud

Programmable