1 operation of remote switch inputs, Db-37 – Rice Lake 520 HMI Digital Weight Indicator Manual - BCD Option User Manual
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8
BCD
Interface Installation and Configuration Manual
3.1
Operation of Remote Switch Inputs
37
34
33
4
3
1
2
DB-37
Zero Switch
Gross/Net
Auto Tare
Hold
Units Select (primary/secondary)
or Tri-State Enable
Logic Common
Logic Common
OFF
ON
OFF
AUTO TARE
GROSS/NET
ZERO
ON
HOLD
(If on, this freezes the BCD registers)
UNITS SELECT (toggles between primary
and secondary) or TRI-STATE Output Enable
(if Tri-State configuration switch is enabled
,
On position enables Tri-State mode)
.
Figure 3-2. BCD Remote Switches
Three of the front panel switches (zero switch, gross/net switch, and auto tare switch), can be operated from a
remote location using momentary-action pushbuttons. Note that each “push” of a remote switch activates the
associated function once. The function of the gross/net switch is to change the state of output between gross and net
mode.
An alternate action switch is suggested to operate the Hold and Units Select/Tri-State Enable. When using the BCD
option in Units mode, the switch state is independent of the front panel and toggles between primary and secondary
units if any change of state is detected.
Tri-State output enable is used to allow other peripheral devices to use the same BCD output. To place the unit in
Tri-State mode, set dip switches according to Table 2-4.
All switch inputs are tied to 5V through pull-up resistors on the BCD option card to ensure reliable operation.
Note
Connect the pins/switches to Logic Common only, not case ground or other grounds.