Delta OHM PMBsense-A, Operating Manual

Page: 10 / 24

PM[B]sense
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V1.3
Note : after sending the DP1 command, the instrument remains with the proprietary protocol.
Send the command SM to activate the MODBUS-RTU protocol immediately, or power cycle the
instrument.
RS485 communication parameters:
Command Reply Description
CMBn &| Sets the Baud Rate:

1200 if n=0 ▪ 19200 if n=4

2400 if n=1 ▪ 38400 if n=5

4800 if n=2
▪
57600 if n=6

9600 if n=3
▪
115200 if n=7
Default : 19200 (n=4)
RMB & n| Reads Baud Rate setting
CMPn &| Sets parity and stop bits:

8N1 if n=0 [No parity, 1 stop bit]

8N2 if n=1 [No parity, 2 stop bits]

8E1 if n=2 [Even parity, 1 stop bit]

8E2 if n=3 [Even parity, 2 stop bits]

8O1 if n=4 [Odd parity, 1 stop bit]

8O2 if n=5 [Odd parity, 2 stop bits]
The number of data bits is fixed to 8.
Default : 8E1 (n=2)
RMP & n| Reads the setting of parity and stop bits.
CMWn &| Sets waiting time after transmission with MODBUS-RTU
protocol:
 Immediate reception if n=0 (violates protocol)

Waiting 3.5 characters if n=1 (respects protocol)
Default : Immediate reception (n=0)
RMW & n| Reads the setting of waiting time after transmission with
MODBUS-RTU protocol.
PM measurement settings:
Command Reply Description
CPLSn &| Sets the PM measurement mode:

Continuous if n=0

At cyclic intervals if n=1
Default
: At cyclic intervals (n=1)
RPLS & n| Reads the setting of the PM measurement mode.
CPLPn &| Sets the cycle interval for the measurement mode at cy-
clic intervals.
Default
: 300 (=5 min)
RPLP & n| Reads the setting of the cycle interval for the measure-
ment mode at cyclic intervals.
CPLOn &| Sets the sensor ON time for the measurement mode at
cyclic intervals to n seconds.
It must be greater than 70 s (warm-up time).
Default : 71
RPLO & n| Reads the setting of the sensor ON time for the measure-
ment mode at cyclic intervals.