Keithley 610C, Instruction Manual

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SECTION 1. GENERAL DESCRIPTION
1-1. GENERAL.
a. The Keithley Model 6l0e Electrometer is a versa­
tile, completely solid-state instrument which measures
a wide range of de voltage, current, resistance and
charge. The Electrometer's input resistance of great­
er than 1014 ohms is the result of extensive instru­
ment development with high input impedance transistors.
The Model 6l0e has all the capabilities of convention­
al VTVMs, but it can also make many more measurements
without circuit loading.
b. The Electrometer has eleven voltage ranges from
0.001 volt full scale to 100 volts, twenty-eight cur­
rent ranges from 10-14 ampere full scale to 0.3 ampere,
twenty-five linear resistance ranges from 100 ohms full
scale to 1014 ohms, and �eventeen charge ranges from
10-13 coulomb full scale to 10-5 coulomb.
c. The Model 6l0C employs matched insulated-gate
field-effect transistors followed by a transistor dif­
ferential amplifier and complimentary output stage.
A
large amount of negative feedback is used for stabili­
ty and accuracy.
1-2. FEATURES.
a. An important feature of the Model 6l0C is its
excellent zero stability which permits accurate mea­
surements with a minimum of adjustment. Zero drift is
less than 1 millivolt per 24 hours. Zero offset due
to temperature change is less than 150 microvolts
per °C, after a 30-minute warm-up: This offset, how­
ever, can easily be compensated for with the front­
panel zero controls.
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FIGt�1 1. Front Fanel Controls.
b. Fast warm up is an inherent characteristic of
this Electrometer. It can be used well within '30 min­
utes of a cold start on the most sensitive range and
almost immediately on less sensitive ranges.
c. Low offset current -- less than 5 x 10-15 ampere
-- minimizing zero offset with high source resistances
and permits maximum resolution when measuring current
and charge.
d. Excellent overload protection without degrada­
tion of performance is obtained by use of a unique in­
put circuit.
The Model 6l0e Electrometer will with­
stand overloads up to 500 volts on most ranges without
damage and has good recovery.
1-3. DIFFERENCES BETWEEN THE MODELS blOC AND b10CR.
a. The Model 6l0eR is the rack version of the cab­
inet configuration, Model 6l0C. The circuit, speci­
fications, electrical parts and operating procedures
for the two models are the same. Besides the outside
dimensions, the main difference between them is the
Model 6l0CRIs COARSE ZERO Control is on the front pan­
el, not on the rear panel.
b. The instructions in the Manual are for both
models, although only the Model 6l0C is mentioned.
FIGu�E 2.
Rear Panel Controls.
1