TB 9-6625-133-40
d. Resistance Adjustments
WARNING
The TI can deliver a lethal electrical shock when operating in
the High Voltage Resistance mode on the 20 MΩ through
20 GΩ ranges (Ω PLUS HiVΩ). Voltages up to 240 V may be
present on the terminals. When connecting or disconnecting
resistors, select Ω, (disabling Ω PLUS Hi VΩ) to remove high
voltage from the terminals. Re-select Ω PLUS HiVΩ as
necessary to make high voltage resistance measurements.
NOTE
Just one range or mode may be adjusted if required, but for a
full adjustment, start with the 2 Ω range and work up to the
2 GΩ range. Zero cal point on all ranges requiring adjustment
may be completed before any range gain adjustments to avoid
multiple connect/disconnects. Zero cal point for any/all ranges
is adjusted in (3) through (7) below; range gain is adjusted in
(9) through (13) below. Any range requiring adjustment must
have both adjustments: Zero and Range Gain.
(1) Set the rear panel CALIBRATION switch to ENABLE (if necessary).
(2) Ensure that table 12 is populated with the test report values of the resistance
standards (transfer values from table A-1) for the ranges requiring adjustment.
(3) Prepare TI for zero point adjustment by connecting equipment as shown in
figure 3. Use high quality low thermal emf leads. Allow adequate time for thermals to
dissipate.
(4) Press TI CLEAR and [PWR UP DFLT]. Set TI to range and resistance mode
requiring adjustment (use table 6 to configure the TI resistance mode). Allow time for TI
indication to settle.
(6) Press SAMPLE to initiate the adjustment. Zero point adjustment is complete
when the BUSY legend goes out.
(7) Repeat technique of (4) through (6) above for remaining TI ranges requiring adjustment.
(8) Disconnect shorted leads.
(9) Connect resistance standard to TI as shown in figure 4 for the range that
requires adjustment. Allow time for TI indication to stabilize.
(10) Press CAL to enter the CALIBRATION menu then press [SET].
(11) Enter the test report value of the resistance standard applied to TI using
numeric keypad, then press ENTER
(12) Press SAMPLE to initiate the adjustment. Adjustment is complete when the
BUSY legend goes out.
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