Epson 5000 - Manual (Page 67)

Control Panel
The indicator lights give you the current status of the printer.
The buttons let you control many printer settings.
Lights
OPERATE (green)
On when the operate switch is on and power is supplied.
PAUSE (orange)
On when the printer is not ready to print data. The PAUSE light
is off unless you press the pause button to prevent printing.
DATA (orange)
On when the printer’s buffer contains data,
MULTI-PART (green)
On when you move the paper-thickness lever to position 2 or
higher. The printing speed is reduced when this light is on.
When this light is flashing, you can use the micro-feed feature.
3-2 Using the Printer