Gossen SI 232-II User Manual

Page of 28
GOSSEN METRAWATT GMBH
25
9
Memory Adapter Technical Data
Supported Measuring Instruments
METRAHit 12S ... 16S, 16I/T, 18S, 14A, 22S/M ... 29S
Operating Elements and Operation
7 segment LCD display and 4 keys.
Almost all parameters can be configured manually, or with a PC via the interface.
Memory
128 kB CMOS memory with battery backup.
Measurement value storage in accordance with the differential value method (compressed) 
with adjustable hysteresis. An average of 50,000, and at least 20,000 measurement values 
are acquired depending upon whether or not significant signal changes or time spans occur 
between the individual measurements. A maximum of 100,000 measurement values are 
acquired if only minimal signal changes occur, if the sampling rate is equal to or less than 
0.5 s and if hysteresis has been set to ALL.
Real-Time Clock
Real-time clock with battery backup. Max. error: 0.5 minutes per month
Interface
To the Multimeter 
Optical receiver/transmitter, 950 nm wavelength, 
8192 / 9600 baud, 8 bits, no parity, 1 stop bit
To the PC
Bidirectional, adjustable baud rate: 9600, 19,200 or 38,400 
baud, 8 bits, no parity, 1 stop bit
Number of Adapters
Up to10 data memory adapters can be interconnected.
The maximum number depends upon the selected sampling 
rate for online PC data acquisition: 
With METRAHit 1x 
up to 6 adapters at a baud rate of 19.2 kBd
up to 4 adapters at a baud rate of 9.6 kBd
With METRAHit 2x
up to 3 adapters at a sampling rate of 50 ms
up to 8 adapters at a sampling rate of 200 ms
Connections
Pin 9 is used for the synchronization of interconnected adapt-
ers in the PC operating mode.
Pins 4 and 7 must be connected to high level at the PC and are 
used to supply electrical power to the data memory adapter. 
Power is drawn from this source by the data memory adapter 
for levels of down to 5 V. Power is drawn from the battery for 
lesser voltage levels.
Pin 3 (PC-TXD) is used for negative level generation of the PC-
RDX signal from the RS232 interface.
With the exception of pin 1 and pin 9 (used for synchroniza-
tion), all of the interface conductors are looped through to 
additional data memory adapters.