PAV LAN
43
Global Commands for Multi-Drop Connection
.
Selecting the PAV
To select the PAV you want to control, send
INSTrument:NSELect <
address
>
A PAV that has been specified by an address (1 to 31) can receive SCPI commands.
Until the above command is received again, all commands and queries are applied only to
the specified PAV.
At power-on, the LAN master unit is automatically selected.
After sending the INSTrument:NSELect<address> command, send an INSTrument:NSE-
Lect? query or SYSTem:ERRor? query to check that the specified RS485 address is correct.
Command example
The PAV status that has been specified by INSTrument:NSELect <address> command is
valid even when a global command is sent until the address is changed.
INST:nSEL 4
:VOLT 50
GLOB:VOLT 70
(Wait 20 ms before sending the next command.)
:VOLT 90
After the command is sent, the output voltage setting of PAVs other than that with address 4
is 70 V.
The output voltage setting of the PAV with address 4 is 90 V. There is no need to send the
INSTrument:NSELect <address> command again.
Responses to global commands
When you send a global command, the command is applied to all PAVs in the multi-drop con-
nection and the PAV with LAN.
As global commands cannot be used to control error and status registers, it must be per-
formed for each PAV separately. Global commands do not comply with SCPI. For details on
global commands, see the USB/RS232/RS485 Communication Interface Manual.
Checking the responses
Check that when you send a SYSTem:ERRor? query to each PAV, none of them returns an
error message. PAVs that return error messages cannot respond to global commands.
Command transmission interval
After sending a global command, wait at least 20 ms before sending the next global com-
mand. If you want to send global command consecutively, allow at least 20 ms between each
global command. Otherwise, commands may not be accepted.
Query syntax
There is no query syntax for global commands. To check the settings of each PAV after send-
ing a global command, you must select the PAV individually and query the settings.
