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47DT OPERATING MANUAL EM-9508-B Rev.7
25. 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.
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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 ‘S.ERR’ and ‘B.ERR’. 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 ‘S.ERR’ and ‘B.ERR’.
• 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 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’ or ‘B.ERR’ is indicated.
• TABLE 1: BCD SIGNALS
SIGNAL
FUNCTION
Input
REQ
Request BCD data
Valid data in approximately 30 milliseconds after detecting the signal’s
rising edge.
MIN_REQ
Request minimum reading data
Valid MIN value data in approximately 30 milliseconds after detecting the
signal’s rising edge.
MAX_REQ
Request maximum reading data
Valid MAX value data in approximately 30 milliseconds after detecting the
signal’s rising edge.
HOLD
Hold data
Reading measured signal stops and the last value is held when the
HOLD signal is turned ON.
RESET
Reset data
• ALL BCD data turn OFF when the RESET signal is turned ON.
• MAX and MIN values and latching alarm are reset.
Output
DATA
(Do11 to Do68)
BCD output data (6 digits)
BCD output data in 6 digits
POL
BCD polarity
Polarity of BCD data. ON = (-), OFF = (+)
OVF
BCD overflow/underflow
Output given at overflow or underflow (‘S.ERR’ and ‘B.ERR’)
DAV
Data valid
Means the BCD data is valid. ON = valid, OFF = invalid
RUN
Run
• Means the meter is functioning.
• OFF = error except the ‘S.ERR’ and ‘B.ERR’
• No DAV or DATA output is given when the RUN signal is not provided.
HH
HH alarm trip output
Follows HH alarm output.
H
H alarm trip output
Follows H alarm output.
P
P status output
Follows P status.
L
L alarm trip output
Follows L alarm output.
LL
LL alarm trip output
Follows LL alarm output.
