5500A/EP Enhancement Package
Users Manual
16
Operating Guidelines
Follow these guidelines carefully when operating the switch accessory.
Caution
Using the 4-Wire Ohms mode for carrying more than 2A can
damage the switch accessory. For currents greater than 2A,
use Current mode, and the A output lead.
Relay clusters 1, 2, and 4 should never carry current above 2A.
Currents higher than 2 amps can damage these relays.
•
Thermal emf errors from self heating can occur if high current outputs are followed
too closely by low-level V dc (<3V) or by resistance. When sourcing current greater
than 2A, wait for a period of twice the amount of time the high current was on before
following the output with low level V dc (<3V) or any resistance outputs.
For example, if 11A was sourced for 30 seconds, wait at least one minute before
sourcing any V dc that is less than 3V, or before sourcing resistance. This eliminates
any self-heating thermal emf errors that may occur.
•
The external 4-wire short is used to establish the absolute zero reference of the
DMM before the switch accessory is connected.
•
The 4-Wire Short Circuit should not be used to provide a low ohms short for 2-Wire
Ohms calibration. Use the 5500A 2-Wire COMP mode instead. To provide a
reference point for 2-Wire ohms calibration, set the switch accessory to 2-Wire
Comp/Normal Ohms mode (UUT_SEND B=) and set the 5500A to 0.000 Ohms, 2-
Wire COMP.
Hint: To set the switch accessory back to its default voltage state, place the 5500A into
standby mode (press
Y
). Once the 5500A is in standby, briefly unplug the BE860
battery eliminator from the switch accessory, and then reinsert it.
Troubleshooting
If you encounter problems during characterization or calibration, check all hardware
connections and check that your MET/CAL software is set up properly as outlined
below. You may wish to consult your Metrology Software manuals for more assistance.
1.
Verify that the MET/CAL directory structure indicates the following:
•
MET/CAL is not in the Runtime Demo mode.
•
ASCII procedure files (*.PRO) must be located in the directory designated
specifically for these files.
•
Picture files (*.BMP) must be located in a directory designated for picture files.
•
The traceability and configuration information is entered correctly as shown in
this manual.
2.
Ensure the system is set up according to the instructions in this manual.
