DH Instruments PPCH-G, Руководство по эксплуатации и обслуживанию

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4. REMOTE OPERATION
Page 115 © 2007 DH Instruments, a Fluke Company
UL
Purpose Read or set an upper limit for the current range.
Command
Query “UL n ”
“UL?”
Classic “UL= n ”
“UL”
Arguments n: The upper limit pressure in the current pressure unit and measurement mode.
Remarks The PPCH-G has an upper limit for each range and for each measurement mode (gauge and
absolute). New automated pressure control targets cannot be greater than this value. If the
pressure does exceed the upper limit, the pressure display flashes, and pressure control
stops. Manual increases in pressure are not allowed as long as the pressure is above the
upper limit. Decreases in pressure are allowed. This feature should always be used to
prevent accidental over pressure of a device under test.
Example
(enhanced) Cmd sent:
Reply: “UL 10”
“10.000 MPa a” (No reply if GPIB-488)
Example
(enhanced) Cmd sent:
Reply: “UL? 10”
“10.000 MPa a”
Example
(classic) Sent:
Reply: “UL=1000”
“10.000 MPa a”
Errors ERR# 6: The argument is out of range.
See Also 3.4.4
UNIT
Purpose Read or set the pressure unit of measure unit and measurement mode.
Command
Query “UNIT unit (, ref ”)”
“UNIT unit g (, ref ”)”
“UNIT unit a (, ref ”)”
“UNIT?”
Classic “UNIT= unit (, ref ”)”
“UNIT= unit g (, ref ”)”
“UNIT= unit a (, ref ”)”
“UNIT”
Arguments unit:
ref:
The text corresponding to the pressure unit of measure.
The optional unit reference temperature only if the unit is “InWa”.
Remarks This program message determines what unit of measure and may determine what
measurement mode is used to display pressure values. Refer to Table 13 for a detailed list of
the units available and their labels.
The unit text must be followed by ‘a’ if absolute measurement mode is desired, or ‘g’ to specify
gauge measurement mode. There can be a space between the unit text and the ‘a’ or the ‘g’.
If neither ‘a’ nor ‘g’ is specified, the unit will change but the measurement mode will remain
the same.
If the unit specified is “InWa”, an optional second argument “
ref” can be set. The “ref” can be
4, 20, or 60 corresponding to InWa at 4 °C, 20 °C or 60 °F. If this second argument is not
given when the unit is “InWa”, then the reference temperature is assumed to be 20 °C. he fifth
character of the reply is always ‘a’ for absolute mode, or ‘g’ for gauge mode. White spaces will
proceed this character if needed. The temperature reference is added to the reply only if the
unit is “InWa”.
Example
(enhanced) Cmd sent:
Reply:
Sent:
Reply: “UNIT kPaa”
“kPaa”
“UNIT InWag, 4”
“inWag, 4”
Example
(classic) Sent:
Reply:
Sent:
Reply: “UNIT=kPaa”
“kPa a”
“UNIT=InWag, 4”
“inWag, 4”
Errors ERR# 7:
ERR# 6:
The unit is invalid.
The ref is invalid.
See Also “MMODE”, “MODE”
3.3.2, 3.3.3