Fluke 5560A - How to Use an External 10 Mhz Clock; Sample Applications

5560A/5550A/5540A
Operators Manual
54
To show the Sync button:
1. Go to Setup > Instrument Setup.
2. Tap the Set button under Defaults.
3. Scroll down to Multi-Unit Phase Synchronization Button and select Show.
Set up your multiphase system as in one of these configurations:
• Complete standalone system, where the primary unit is set to internal clock and all secondary units
are set to external clock. The clocks are all daisy chained in a ring. This system does not need a
Sync button.
• Same as above, but without a ring configuration. In this case the primary unit needs the Sync button
displayed.
• The entire system will be locked to a house 10 MHz standard. In this case all units have to be set to
external clock and the Sync button needs to be displayed on the primary unit.
Another use for the 10 MHz IN reference input is to improve the frequency performance of the
Calibrator by injecting a reference 10 MHz clock signal.
How to Use an External 10 MHz Clock
The Calibrator uses an internal 10 MHz clock signal as a reference for all ac functions. Although this
internal clock is very accurate and stable, you may have a lab standard that you want to govern the
frequency performance of the Calibrator. To apply an external clock to the Calibrator, you can make
external reference the power-up and reset default condition.
To make external reference the power-up and reset default setting:
1. Tap the Setup softkey.
2. Select Instrument Setup from the Setup Menu.
3. Under Defaults, tap Set.
4. Scroll the screen up to reach the Reference Clock options.
5. Tap the radio button for Internal or External.
6. Tap Back to go to the prior Setup Menu screen or Exit to close the Setup Menu.
Sample Applications
See the subsequent sections for sample calibration examples for these models.
• Fluke 77 Series IV Digital Multimeter (DMM)
• Fluke 51 Digital Thermometer
The Calibration process is made up of two procedures:
• Verification of the Device Under Test (DUT) that tests each function and range for compliance to
specifications.
• Adjustment of the DUT so that it meets the performance test ranges.