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How can the E4416A/E4417A/E4418A (EPM441A)/E4418B/E4419A (EPM442A)/E4419B memory be erased for security purposes?

There is a power-on keypress combination that can be used to perform a complete wipe of the power meter's memory (both volatile and non-volatile battery-backed-up RAM). The only area of memory unaffected by this wipe process is the instrument firmware, which is stored in Flash EEPROM.

Important Note 1: This procedure erases all user settings, and returns the unit back to it's factory default state. A side-effect of this wiping process is that the unit may also have it's ID information erased - this information should be noted beforehand, and re-programmed afterwards. To clarify this further:

  • E4418A/18B/19A/19B: These units will always lose their ID information.
  • E4416A/17A: Most units will retain their ID information, due to a change in the way it is stored. However, some older units are similar in design to the E4418x/19x models, and as such they will lose this information.

Important Note 2: Only GPIB interface is allowed to send the following SCPI commands remotely.


Step 1 - Note Unit ID Information.

Use the following SCPI commands to extract the relevant data -
Serial Number - SERV:SNUM?
Proc. Bd. Version - SERV:VERS:PROC?
System Number - SERV:VERS:SYST?
Installed Options - SERV:OPT?

If you do not have a computer you can extract the relevant data manually by -

Serial Number - Can be obtained from the serial number label on the back or bottom of the instrument.
Proc. Bd. Version - Can be gotten by pressing the following front panel buttons:SYSTEM->MORE->SERVICE->VERSION
System Number - Can be gotten by pressing the following front panel buttons:SYSTEM->MORE->SERVICE->VERSION
Installed Options - Can be obtained from the serial number label on the back or bottom of the instrument.


Step 2 - Erase Memory.

Press, and then release, the Power button to switch off the unit. Once the unit is switched off, press and hold down the third softkey (third key below PREV), and then press the Power button to switch the unit back on. Release both buttons. The unit display will briefly display "Clearing Memory", after which it will perform its internal self-test and power up sequence.

Note: During self-test, the unit may indicate a RAM Battery Failure (in the case of E4418A/18B/19A/19B units) or a Lithium Battery Failure (in the case of E4416A/17A units). This will also cause a "HW ERROR" to appear in the error queue. If these failures should occur, they can be cleared by simply power cycling the unit. Please note that this is not a hardware failure.


Step 3 - Re-program Unit ID Information.

Use the following SCPI commands to replace the relevant data (replacing x with the correct values) -
Serial Number - SERV:SNUM xxxxxxxxxx
Proc. Bd. Version - SERV:VERS:PROC "x"
System Number - SERV:VERS:SYST "x"
Installed Options - SERV:OPT "xxx"

This information can not be entered from the front panel, and must be entered using the SCPI commands.


Step 4 - Power Cycle.

The unit should be power cycled to ensure it is operating in the correct mode. Changing the ID variables of the unit will enable/disable various features and functions in it, and a power cycle will ensure that it starts in a known operational state.