Setting Bcd Output - M-system 47DAC Operating Manual

22. SETTING BCD OUTPUT

Measured values can be taken in a PLC or a large scaled display. The BCD output, 5 alarm outputs including the P status
output can be provided. Also with external contact signals, the measured value can be held, and MAX/MIN values and
latching alarm can be reset. The input and output logic can be set.
■ BCD OUTPUT SIGNALS
• A request signal (REQ, MAX_REQ, or MIN_REQ) from an external device including a PLC is required to read out the
BCD data. Refer to Table 1 for the signals.
• The DATA signal (Do11 to Do68) is established in approximately 30 milliseconds upon detecting the falling pulse edge of
a request signal and the DAV signal turns ON. Read in the data while the DAV is ON.
The RUN signal turns OFF in case of errors other than the scaling error. The DATA and DAV signals turn OFF while the
RUN signal is OFF.
The last measured value is held when the HOLD signal turns ON.
All BCD signals turn OFF when the RESET signal turns ON.
The OVF signal turns ON in case of the scaling error.
• While in Loop Test Output Mode, the analog/alarm outputs are provided according to the display reading, even when a
request signal is turned ON.
• The LL, L, H and HH signals turn ON/OFF according to the respective alarm status. The P signal does likewise.
NOTE
• The BCD output includes the P status output. The alarm output set with the P output parameter can be also provided.
• The Forced Zero and Tare Adjustment cannot be executed or canceled for no measured data (RESET signal ON).
• The MAX and MIN values can be reset with the RESET signal ON regardless of the MAX/MIN display control lockout
setting.
• The front button control of the MAX and MIN values does not affect the BCD output. Provide the MAX_REQ or MIN_
REQ signal.
• Present, MAX and MIN values can be output even while 'S.ERR' is indicated.
• TABLE 1: BCD SIGNALS
SIGNAL
Input REQ
MIN_REQ
MAX_REQ
HOLD
RESET
Output DATA
(Do11 to Do68)
POL
OVF
DAV
RUN
HH
H
P
L
LL
Request BCD data
Request minimum reading data
Request maximum reading data
Hold data
Reset data
BCD output data (6 digits)
BCD polarity
BCD overflow/underflow
Data valid
Run
HH alarm trip output
H alarm trip output
P status output
L alarm trip output
LL alarm trip output
FUNCTION
Valid data in approximately 30 milliseconds after detecting the signal's
rising edge.
Valid MIN value data in approximately 30 milliseconds after detecting the
signal's rising edge.
Valid MAX value data in approximately 30 milliseconds after detecting the
signal's rising edge.
Reading measured signal stops and the last value is held when the
HOLD signal is turned ON.
• ALL BCD data turn OFF when the RESET signal is turned ON.
• MAX and MIN values and latching alarm are reset.
BCD output data in 6 digits
Polarity of BCD data. ON = (-), OFF = (+)
Output given at overflow or underflow (scaling error)
Means the BCD data is valid. ON = valid, OFF = invalid
• Means the meter is functioning.
• OFF = error except the scaling error
• No DAV or DATA output is given when the RUN signal is not provided.
Follows HH alarm output.
Follows H alarm output.
Follows P status.
Follows L alarm output.
Follows LL alarm output.
47DAC OPERATING MANUAL EM-9518-B Rev.4 179