Epson EPL-6100 Reference Manual page 167

Note:
Settings made in the Remote Control Panel utility are not effective until
you click Execute.
Standby
Allows you to set the Standby mode to Enable (default) or
Disable. When Standby is enabled, the printer goes into sleep
mode if it is not used for 15 minutes. The printer begins warming
up as soon as you send data, and is ready to print in about 11
seconds. When Standby is disabled, the printer stays warmed up
and ready to print all the time.
MP Tray Paper Size
You can set the paper size in the MP tray here.
Note:
The custom size paper set in the printer driver is not selectable here.
The Page Size options are as follows:
A4 (default)
A5
B5
LT (Letter)
HLT (Half letter)
LGL (Legal)
GLT (Government letter)
GLG (Government legal)
EXE (Executive)
F4
MON (Monarch)
C10 (Commercial 10)
DL
C5
C6
IB5 (International B5)
Using the Remote Control Panel Utility
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