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C.12 Option 28: Power System Time, Frequency and Phase Monitor
119
C.12.6
Phase Calibration
Phase calibration has been performed at the factory, and the calibration factor (which must be
entered into the clock non-volatile memory for it to be effective) is supplied with the assembly.
Entering this factor into the clock requires connecting the clock to a computer or terminal via the
RS-232 interface. For the computer, use a terminal-emulation program such as Procomm, Windows
HyperTerminal or Tera Term Pro
. Send the character V to the clock to check that connections
and port settings are correct. The clock should respond with the firmware dates in the format 01
Jan 1997 Op28 02 Jan 1997.
To send the phase calibration factor to the clock, key in the message:
dd.dd,1084PC, or
dd.dd,1088PC, or
dd.dd,1093PC
Where dd.dd is the calibration factor in degrees, for example -0.16; and 1084, 1093 or 1088 is
the clock model number (a security key to prevent unintentional modification):
-0.16,1084PC
C.12.7
Amplitude Calibration
For amplitude calibration, the format is similar, replacing PC with RV. The calibration factor
(supplied with boards having a serial number with prefix greater than 97420) is approximately
1.0, and is multiplied by the measured result to generate the displayed value. If an accurate ac
source at 50 or 60 Hz is available (for example, the Arbiter Systems, Inc. Model 1040C Panel
Meter Calibrator), the error (for boards with prefix 97420) can be measured and the correction
factor entered as described. For example, if 120 Vrms is applied to the Option 28 assembly, and
the display indicates 119.1 Vrms, the calibration factor is (120.0 / 119.1) or 1.0076. You would
enter 1.0076,1093RV to calibrate the unit (Model 1093A/B/C). The display should then read close
to 120.0 Vrms. To clear the calibration factor, you may set the unit to factory defaults or send the
command 1,1093RV. Again, use either 1084, 1088 or 1093 to match the clock model number.
C.12.8
Option 28–Specific RS-232 Commands
The following symbols and syntax are used throughout the RS-232 Commands listing and are
repeated here for emphasis:
C
Shorthand for Carriage–Return, Line–Feed.
A
Channel A.
B
Channel B.
U
UTC Time, Channel A (or B).
L
Local Time, Channel A (or B).
Fourteen (14) new RS-232 commands are available with Option 28. The following conventions
apply to all RS-232 communications:
•
Phase angle, in all messages, is defined as zero (or 360) for the positive-going zero crossing
coincident with 1 PPS-GPS, and is scaled between zero and 360 degrees. Phase angle increases
1
To download Tera Term Pro, see the Arbiter Website and select “Service/Support
>
Downloads.”
Содержание 1092A
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Страница 129: ...C 10 Option 20A Four Fiber Optic Outputs 111 Figure C 7 Option 20A Jumper Locations ...
Страница 131: ...C 11 Option 27 8 Channel High Drive 113 Figure C 8 Option 27 Jumper Locations ...
Страница 148: ...130 Options List Figure C 10 Option 29 Connector Signal Locations ...