Operating Procedure - Time Electronics 1024 User Manual

Time Electronics
1024 DC Current Calibrator
2.2

Operating Procedure

2.2.1 Normal Operation
Operation of the 1024 is self-explanatory from the front panel controls and specifications. It is
important to understand the 1024's voltage capability and voltage limit indicator to ensure that
your requirement is within the limit. It is also important to read the section on output noise if
your requirement is for current levels of less than a few tens of microamps.
When the 1024 is operating from batteries and required to supply currents in excess 10 mA it
is important to check the battery condition with the load connected since the battery's
condition may be adequate for sourcing low output currents but not higher current.
Measurement of an unknown current:
1) Select 'NULL' position on the front panel function switch.
2) Select 'NORMAL' output.
3) Adjust 'SENS' for minimum sensitivity (fully anticlockwise).
4) Select range consistent with the expected current to be measured.
5) Connect the unknown current to the terminals in the same polarity i.e. unknown current
flows into the + Ve terminal.
6) Adjust digit switch and sensitivity control for null balance (0) on meter as required.
7) When balance at required sensitivity is reached the unknown current is equal to the digit
switch setting.
Overload conditions
The 1024 can withstand indefinitely either short or open circuit on the output terminals.
Overload conditions can easily result if any attempt is made to drive current into the 1024 by
applying a voltage to the output terminals. In most cases this will cause the output fuse (See
Section 2.5) to blow but can still cause damage to the output circuitry.
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