Keysight 53220A - Standby Power; Table 2-2 Table; Power-On LED Status and Color

1 Preparation for Use
30 Keysight 53220A/53230A User’s Guide
Standby power
The power modes of the 53220A/53230A counter are ‘on’ ‘off’, and ‘standby’. In
standby mode with the instrument connected to line voltage, standby power is
supplied to maintain the temperature within the ultra high-stability oven
controlled crystal oscillator (Option 010).
Battery Option 300 itself supplies standby power for the OCXO when the 53220A/
53230A is not connected to line voltage.
Refer to Chapter 3, "Standby power to the reference oscillator (Option 010)" for
information on enabling/disabling standby power.
Cycling power and counter accuracy
With standby power enabled, repeated power cycling (line or battery) does not
affect the standard or ultra-high stability OCXO.
Table 1-2 Power-on LED status and color
Instrument ’Off’
Power Source Instrument ‘On’
OCXO w/ Standby
enabled
OCXO w/ Standby
disabled
No OCXO
AC Line green amber off off
Opt. 300 Battery
(enabled)
green amber (blinking) off off
Opt. 300 Battery
(disabled)
off off off off