Rdd100 user guide – Honeywell RDD100 User Manual
Page 5

RDD100 User Guide
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Resp *99WE
(Command
Echo)
Type
*99du= {selection-see DU list below}
(A list of available pressure display units can also be found in the associated transducer User’s Manual.)
Resp
*99DU= {selected display units} (Command Echo)
Display Units List
Display Unit
PSI Multiplier
Units Description
ATM 0.068046
ambient atmosphere at sea level
BAR
0.068948 bar
(10
5
newtons/meter
2
)
CMWC
70.304
centimeters of water column (4ºC)
FTWC
2.3065
feet
of
water
column
(4ºC)
INHG
2.0360
inches
of
mercury
(0ºC)
INWC
27.679
inches
of
water
column
(4ºC)
KGCM
0.070307 kilograms/centimeters
2
KPA
6.8948
kilopascal
MBAR
68.948
millibar
(1
hectopascal)
MMHG
51.714
millimeters of mercury (0ºC) or torr
MPA
0.0068948
megapascal
MWC
0.70304
meters
of
water
column
(4ºC)
PSI
1.0000
pounds
per
square
inch
USER
0.0010000-999.99
user
supplied
LCOM
FS=60000
logic
common
value
(1)
PFS
FS=100.000
percent of full scale in 0.001%
Increments
(1)
The LCOM display unit (logic common) automatically switches the digital pressure output to a scale, which has
60000 as the full scale output. The output will have a decimal point in the same position as it was in the original
psi scale. For example, when a 10 psia device is switched to DU=LCOM, the full scale digital pressure output will
be 60.000, instead of 10.000. Also, a 500 psi device will output full scale 600.00 instead of 500.00. PFS
generally provides the highest readout resolution available when using the RDD100 readout.
2.5
“Continuous Transmit” Mode
Type *99we
Resp *99WE
(Command Echo)
Type *99mo=p2
(Continuous Pressure Transmit Command)
Resp *99MO=P2
(Command Echo)
2.6
Changes Stored In EEPROM
Type *99we
(Write Enable Command)
Resp *99WE
(Command Echo)
Type *99sp=all
(Store Parameters Command)
Resp *99SP=ALL
(Command Echo)
2.7 Verifying
Stored
Parameters
After cycling power to the transducer the RDD100 should now display pressure readings in the selected display
units. If there is a need to interrogate the transducer to observe its set-up parameters, this can be done using the
following sequence:
Type *99du
Resp *99DU=INHG
(If transducer is set to read inches of mercury)
Although the Display Units example was used, this method of interrogation will work with any of the set up
parameters, listed above and in the associated User’s Manuals.
Note: Since pressure units are not a part of the RDD100 display, the user may want to attach a sticker or some other
indication of the pressure units either on or near the display window.