User`s guide

Operating and Programming 3
L4400 User’s Guide 49
Table 3-1. L4400 LED Definitions and Instrument Status.
LED Color
Condition
ATTN
LAN
PWR
Off
Off
Off
Instrument is not turned on, and may or may
n
ot be connected to line power.
ATTN
LAN
PWR
flashing
flashing
Green
Power-on/boot-up. ATTN and LAN
will flash
red and then green during the power-on
self-test.
ATTN
LAN
PWR
Off
Green
Green
LAN connection
- instrument has an IP address
ATTN
LAN
PWR
Off
Green (flashing)
Green
Instrument identificat
ion. Activated from
instrument Web interface:
ON:
Turn on Front Panel Interface Indicator
OFF: Turn off Front Panel Interface Indicator
ATTN
LAN
PWR
Off
Red
Green
No LAN connection due to:
- disconnected LAN cable
- failure to acquire an IP address
- waiting for DHCP-assigned address
ATTN
LAN
PWR
Red (flashing)
Green
Green
Instrument programming error or self-test
e
rror. Error queue is read using 
SYSTem:ERRor?
ATTN
LAN
PWR
Green (flashing)
Green
Green
Instrument Busy State
- firmware download
- lengthy instrument operation in progress