Series 2280 Precision DC Power Supply Reference Manual  Section 7: SCPI command reference 
077085503 / March 2019  7-121 
 
:SYSTem:LFRequency? 
This query returns the line frequency that was automatically detected when the instrument was turned on. 
Usage 
:SYSTem:LFRequency? 
Details 
The instrument automatically detects the power line frequency when the instrument is powered on. 
Power line frequency can be 50 Hz or 60 Hz. 
Example 
 
Return the line frequency.  
Also see 
None 
 
:SYSTem:PASSword:LOCK 
This command sets a remote interface to lock mode. 
Usage 
:SYSTem:PASSword:LOCK <password> 
 
The password for remote connection 
Details 
When password protection is enabled, sending this command disables the remote interface. For 
example, if you send this command through the GPIB interface, GPIB is locked and the instrument 
ignores all the SCPI commands from the GPIB except the following command: 
:SYSTem:LOCal 
Example 
 
Disable the current interface 
Also see 
:SYSTem:PASSword:MODE (on page 7-122)   
:SYSTem:PASSword:NEW (on page 7-122) 
:SYSTem:PASSword:UNLock (on page 7-123)