Chapter 3
30
Mini-Convectron Module with RS-485
Instruction Manual - 275545
RD
ReaD Convectron pressure response
Example:
From host:
#01RD CR
From Mini-Convectron:
*01_9.34E-02 CR
Notes:
__ = space, CR = carriage return.
ASCII string representing pressure in
scientific notation.
Three significant digits except in 10
-3
Torr range with 2 significant digits and
a zero filler, 10
-4
range with 1 significant digit with 2 zero fillers.
While at vacuum, the readout may be -0.00E-00. This occurs when the
transducer voltage at vacuum has drifted lower than that set by the “TZ”
command. The number received at vacuum will fluctuate under normal
operation but if it reads negative consistently, calibration may be required.
See .
Another possible response from RD is ?01_DEF_SNSR. There are three
possible causes for this response:
1.
Defective transducer, see Chapter 5.
2.
Pressure much higher than 1000 Torr.
3.
Gases other than nitrogen in system. Atmosphere pressure of helium
will cause this response.
SA
Set Offset Address
Example:
From host:
#01SA20 CR
From Mini-Convectron:
*01_PROGM_OK CR
Notes:
The address selector setting is added to this value. Example: address
selector is set at 2 and offset value is 20 then the module address is 22. The
operating address will not change until the power is cycled or RST is sent.
