16
Remote/Local Operation
At power-on the instrument will be in the local state with the REMote indicator off. In this state all
front panel operations are possible. When the instrument is addressed to listen and a command is
received the remote state will be entered and REMote will be turned on. In this state the front panel
is locked out and remote commands only will be processed. The V/I settings, V
TRACK
status and
output states are unchanged but LOCK is cancelled (if it was on) and both range settings are
defaulted to 60V/10A. The Sense settings remain as set by the front panel switches.
The instrument may be returned to the local state by pressing the LOCAL key; however, the effect
of this action will only remain until the instrument is addressed again or receives another character
from the interface, when the remote state will once again be entered. Returning to Local by this
action, or by the use of the LOCAL command, will keep the V/I settings at their last remotely set
values, with LOCK on, and will leave the outputs in their present state.
V
TRACK
, if set in remote mode, will stay set when returning to Local. Output 1 is LOCKed but not
Output 2; however, it effectively stays ‘locked’ because it is tracking Output 1.
RS232 Interface
RS232 Interface Connector
The 9-way D-type serial interface connector is located on the instrument rear panel. The pin
connections are as shown below:
Pin
Name
Description
1
RI
Passively asserted (+V through 10k
Ω
)
2
TXD
Transmitted data from instrument
3
RXD
Received data to instrument
4
CTS
5
GND
Signal ground
6
RTS
Passively asserted (+V through 10k
Ω
)
7
DSR
No internal connection
8
DTR
9
CD
No internal connection
RS232 Connections
The RS232 interface should be connected to a standard PC port using a fully wired 1:1 male-
female cable without any cross-over connections. Alternatively, only pins 2, 3 and 5 need be
connected to the PC, but with links made in the connector at the PC end between pins 1, 4 and 6
and between pins 7 and 8, see diagram.
