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1021 Technical Manual
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1.
Introduction
1.1. General Description
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100mA output with overload protection
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0.02% Accuracy
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Wide range of applications
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Safety terminals
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Removable protective boot
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Battery level indicator
The
1021
is a precision DC Current Source suitable for calibration and test applications from
100nA up to 100mA.
The 100mA output with overload protection is based on the popular Time Electronics type
1007 millivolt source and incorporates many of the well-proven features. The instrument is
overload protected and a front panel indicator shows when insufficient drive voltage is
available. The terminal output voltage is adjustable between 14 volts and 40 volts, with a
maximum output power of 2.4 watts.
The unique circuit design ensures that it stays well within specification for at least 12
months. Variation with temperature is better than 60 ppm per ºC, and typically better than
20 ppm per hour at constant temperature. To improve the switch reliability, additional back-
up contacts have been used – even if a contact fails, the 1021 will still operate correctly.
The accuracy and stability are such that a wide range of applications are possible. In the
process industries it may be used to test and calibrate current sensitive transducers, and
their associated indicating and recording instruments. The semiconductor industry requires
constant current sources for parameter measurements. It may also be used to measure DC
current accurately by using the null facility to back off the unknown current. Resolution of
1µA is possible.
The 1021 is housed in a robust metal case and a removable protective boot is supplied as
standard. The front panel safety terminals are compatible with 4mm shrouded plugs, as well
as standard plugs, bare wires, and spade terminals.
Rechargeable batteries give portable operation and a mains recharger is supplied with the
unit. Complete recharge time is 10-12 hours although sufficient charge for a few hours
operation can be obtained with only 1/2 hours’ charge. Overnight recharge is sufficient to
fully charge the batteries, which give up to 10 hours of typical operation. The mains
recharger is supplied as standard with the 1021 and connects with a socket on the top
panel.