2 floating decimal point, 3 polarity switch, 2 floating decimal point 3.3 polarity switch – Rice Lake 520 HMI Digital Weight Indicator Manual - BCD Option User Manual
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BCD
Interface Installation and Configuration Manual
3.2
Floating Decimal Point
A BCD receiving device must assume the decimal point in a single location for either units (no decimal point is
actually sent on the BCD lines). The BCD offers several configurations for aligning the decimal point. Refer to
Table 2-5 for dip switch settings.
With switch SW1-1 closed (logic 0), the decimal point is rotated left. The BCD option automatically adjusts for the
floating decimal point to accommodate units-switching on fixed decimal point devices. It adjusts the decimal point
of the units with fewer decimal digits, to match that of the units with the most decimal digits.
Example:
2721 lb — transmits as 27210 — is interpreted as 2721.0 lb
1234.5 kg— transmits as 12345 — is interpreted as 1234.5 kg
The receiving device interprets the decimal point at one place.
Switch SW1-2, when closed (logic 0), shifts the weight data of the primary units to the right one place (if it is
configured with a fixed zero), dropping the least significant digit. This function is primarily used to condense the
weight data to five and one-half digits by eliminating the fixed zero from the parallel output.
Example:
Table 3-2. Floating Decimal Point Example
Displayed Weight
Parallel Output
5th SD
4th SD
3rd SD
2nd SD
LSD SD
Fixed Zero on Receiving
Device
252350 lb
2
5
2
3
5
0
Note
With both switches closed, no rotation is performed.
3.3
Polarity Switch
The BCD option returns polarity on pin 9. The polarity logic may be reversed by setting switch SW1-3. See
Table 2-6 below for information on polarity switch configuration.