iseg SHQ 122, Operator'S Manual

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S p e z i a l e l e k t r o n i k G m b H
iseg Spezialelektronik GmbH Email: sales@iseg-hv.de Phone ++ 49 (0)351 / 26 996 – 0
Bautzner Landstr. 23 http://www.iseg-hv.com Fax ++ 49 (0)351 / 26 996 – 21
14 D - 01454 Radeberg / Rossendorf Germany
5 RS232 interface
The following functionality is provided for the operation of the high voltage units via the RS232 interface.
RS232 control mode
•
- Write function: set voltage; ramp speed; maximal output current (current trip); auto start
•
- Switch function: output voltage = set voltage, output voltage = 0
•
- Read function: set voltage; actual output voltage; ramp speed; actual output current;
current trip; auto start ; hardware limits current and voltage; status
Front panel switches have priority over software control.
Manual control mode
While the unit is operated in manual control mode, RS232 read cycles are interpreted only. Commands are accepted, but do
not result in a change of the output voltage.
5.1 Specification RS232 interface
The data exchange is character based, the synchronisation for the transfer direction PC to HV-source (input) is performed
using an echo. The data transfer to the PC (output) is asynchronous. Between two characters a programmable delay time
(break) is included to allow the computer to receive and evaluate the incoming data. The default break time setting is 3 ms.
The hardware setting of the RS232 interface is 9600 bit/s, 8 bit/character, no parity, 1 stop bit.
Signal transmission is performed potential free via the RxD and TxD, relative to GND.
The HV-supply is equipped with a 9 pin female D-Sub connector, the connection can be set up using a 1:1 extension cord
(no null modem cable) when a PC is used. The pin assignment is given in table 1. Control signals have to be bridged on the
PC side when a three lead cable is used, also given in table 1.
Table 3: Signal pin assignment
Signal HV-supply PC PC Connection
RS 232 DSUB9 Internal DSUB9 DSUB25 3-lead cable
RxD 2 2 3
TxD 3 3 2
GND 5 5 7
4
─┐
4 20
─┐
6
─┤
6 6
─┤
8
─┘
8 5
─┘