158
Options List
C.16.5
Calibration
The clock is now configured for operation. Calibration for phase and amplitude are not necessary for
most applications, however if necessary, can be performed. Specifically, these calibrations have no
effect on system time and frequency measurements, and are unnecessary if only time and frequency
are required.
Uncalibrated phase accuracy is usually less than 0.3 degree, and can be reduced to 0.1 degree typical
and 0.2 degree guaranteed with calibration. Uncalibrated amplitude accuracy is usually less than
1%, which is the typical performance of this measurement. Amplitude accuracy is not guaranteed,
and amplitude measurements are provided primarily to verify that the unit is properly connected
and receiving the expected signal level.
C.16.6
Phase Calibration
The factory performs phase calibration, and supplies the calibration factor with the assembly. To
be effective, it must be entered into the clock non-volatile memory. Entering this factor into the
clock requires connecting the clock to a computer or terminal via the RS-232 interface (see clock
manual). For the computer, use a terminal-emulation program such as Windows HyperTerminal or
Tera Term Pro (see Arbiter website). 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.16.7
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 applying 120 Vrms 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 “1.0076,1084RV” to calibrate the unit (model 1084B/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 “1,1088RV.” Again, use either 1084, 1088 or 1093 to match the clock model number.
Summary of Contents for 1084A
Page 4: ...iv ...
Page 6: ...vi ...
Page 18: ...xviii LIST OF FIGURES ...
Page 24: ...4 Unpacking the Clock ...
Page 36: ...16 Connecting Inlet Power Input and Output Signals ...
Page 44: ...24 GPS Antenna and Cable Information ...
Page 114: ...94 Startup and Basic Operation ...
Page 123: ...B 4 Physical Dimensions 103 Figure B 1 Suggested Mounting of the AS0094500 Surge Arrester ...
Page 124: ...104 Using Surge Arresters ...
Page 134: ...114 Options List C 6 2 Option 06 Firmware Setup Figure C 3 Option 06 Firmware Setup ...
Page 142: ...122 Options List Figure C 5 Option 06 Output Jumper Settings ...
Page 158: ...138 Options List Figure C 13 Option 17 Board Layout and Jumper Locations ...
Page 163: ...C 13 Option 20A Four Fiber Optic Outputs 143 Figure C 14 Option 20A Jumper Locations ...
Page 170: ...150 Options List Figure C 16 Option 23 Internal Jumper Setup ...
Page 172: ...152 Options List Figure C 17 Option 27 Jumper Locations ...
Page 190: ...170 Options List Figure C 20 Option 29 Connector Signal Locations ...
Page 246: ...226 Options List ...