Fluke 721-1601, Руководство по калибровке

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721
Calibration Manual
12
Calibration Adjustment
The Product has an electronic calibration process. There are no mechanical
adjustments and the calibration is done with the case closed. A serial
communications port is used for the calibration process to send commands and
receive readings. The normal RS232 interface is used. Calibration can be done
with a terminal program or an automated-calibration program can be written with
programs like MetCal. In this manual, only the serial terminal mode is described.
Table 2 lists the required equipment.
Initiate Communication
Terminal communications can be set up with terminal communication software
on a PC such as Hyperterminal or Ucon. Connect the RS232 cable to the 5-pin
Lemo on the side of the Product. Connect the other end of the cable to the
terminal/PC serial port.
The terminal settings need to be set as follows:
•
Bits per second: 9600
•
Data bits: 8
•
Parity: None
•
Stop bits: 1
•
Flow control: none
•
Local echo: on
First, enable the full-command set by sending HC_GASUI_OFF . Check that it
turned off by sending HC_GASUI?, The Product should reply OFF. All calibration
commands are done on the functions selected on the lower display. Use the
following command sequence to turn off all but the lower display:
DISPLAY UPPER, OFF DISPLAY MIDDLE, OFF DISPLAY LOWER, ON
As long as the Product has been at a stable temperature, within the range of
20
°
C to 26
°
C for an hour or longer, the Product only needs 5 minutes to warm
up. If temperature conditions were previously below 10
°
C or higher than 40
°
C,
then the unit must be allowed to stabilize for a minimum of 3 hours prior to
calibration.