8
Front Panel Keys
Hard Keys
The PC-820 is a 12” x 14” scale with an attached 5” x 12” display housing.
See Figure 1. The scale base is cast aluminum enclosing a QDT
®
(Quartzell
®
Digital Technology) weight sensor and electronics package. The scale platter
is stainless steel.
Figure 1
PC-820 front panel
The display is a 64 x 240 dot matrix which allows several lines of text and the
ability to display graphics. See
Appendix A: Available PC-820 Displays.
There are five softkeys located directly below the display, a numeric keypad
to the right and six other labeled keys. The keys will be described in the next
section.
Built into the PC-820 are two RS-232 serial ports (Com1 and Com2). Com1
can also be used as an RS-485 port. See the
PC-820 Service Manual for
information on setting up Port 1 as RS-485. Com2 can be a bidirectional RS-
232 port or a printer, keyboard and scanner port.
This scale has an internal database and an option card to support a remote
Quartzell
®
or analog base.
The keys on the front panel of the PC-820 are of two types; hard keys and
softkeys. Hard keys are labeled directly and softkey labels appear on the
display. Softkeys function differently at different times and their labels change
as needed.
Below are brief descriptions for each of the hard key functions:
ESCAPE
Press the ESCAPE key to back out of menus or cancel a
numeric entry without accepting the value.
ZERO
Press the ZERO key to establish a zero reference. When the
scale is at zero, ±¼ division, the center-of-zero icon will be
displayed. When the scale is in motion the stable scale icon
will disappear. See note at left.
TARE
With an empty container on the scale, press the TARE key
to enter an active tare weight. The display shows net weight.
ENTER
Press the ENTER key to accept displayed information,
whether it is numeric characters you have keyed in or if it is
a choice displayed while in the menus.
PC-820 Description
To increase the contrast of the
display, press and hold the
CLEAR
and 9 keys until the
desired contrast is reached. To
decrease contrast, press and
hold the CLEAR and 3 keys.
Stable scale
icon
Center of zero
icon
