lNSTRUCT,lON MANUAL
MODEL 610A, 610R
MULTI-PURPOSE ELECTROMETER
AND ACCESSORIES
MODEL 610A
TAHLI. 01: CfIKTEh’TS
Section I.
Section II.
Specifications . . . . . , , . . , . , . . . . ,
Description. . . . . . . . . . . . . . . . . . . 1 1 1
Section III.
Voltmeter. . . . . . . . . . . . . . .
Ammeter. . . . . , . . . . . . . . . . 1 1 1 1 1 1 1 ,
Ohmmeter . . . , . . . . . . . . . . . . . . . . . . . .3-4
Standard Resistance Check,,, , . , . . . , . . , .
The Hegulated power Supplies , . , . . . . , . . , : :
Section IV.
Preparing the Instrument for Operation . . , , , . , . .4-l
Measuring Vo’ltage. . , , . . , . . , . . . . . ,
MeasuringCurrent......
>!easuring Resistance . , , , 1 , , . , , , ,
Internal Resistor Check, , , , , , . . . . , : : : : : .4-4
Internal Voltage Check , , , . , . . . . , . . , . . . .4-4
Using External Indicators. . . . . , . . . . . . . a . -4-4
Miscellaneous Applications , , , . . , . . . . . . , . .4-S
Zero Center Operation. . . . , , . . , . . . . , . . . .4-6
‘Title
Introduction. . . , . . . . . . . . . . . . . . .1-l
Specifications and Description . , . , . , , . .2-l
Circuit Description . . , , , , , . , , . . , .3-l
Operation. . . , , . . . . , , , , . , . . . , .4-l
. . . . . . . . . . . .
m
.2-l
.?-2
. .3-l
.3-3
.3-7
.3-7
.4-2
Section V.
Section VI.
Trouble Shooting , , , , , , , , , , , , , , , , , . . .6-l
Recalibrating power Supplies , . ,
Replaceable Parts List . . , , , , : : : : : : : : : :
Voltage and Resistance Chart . . , , , . , , , . . . . .6-9
Schematic Diagram. . . , , , , , . . . . . . . , , , . .6-11
*Change Notice. , . , . , . , , , , , , , , , , , , , , .Last
*If a change in the instrument affects the instructions, the correction is printed on a yellow sheet at the back of the manual,
0862R
Accessories , . , , , , , , . . . , . , . . . , -5-l
Xaintenance. . . , . . . . . . . . . . . . . .
.6-l
.6-2
.6-S
Page
i
MODEL 610A
INTRODUCTION
SECTION I
The Keithley Model 610A Electrometer is an ultra-high impedance
voltmeter with full-scale ranges of 0.01, 0,03, 0.10, 0,30, 1.0,
3.0, 10, 30, and 100 volts,
on all ranges,
The maximum input resistance is greater than 1014 ohms; in addi-
tion
ohm io
instrument, Thus, ~the 610A is not only appropriate for measure-
ment in high-impedance circuits, but also can be used where a high
input impedance would merely introduce unwanted pickup,
The 610A may be used as a direct-reading ammeter from 3 amperes
to lo-l3 ampere full scale, This 14-decade range is covered in
overlapping 3x and l?poscales. Accuracy is within 3% of ful’l
~;“~031y~;;~;e~o lo
Two current measuring methods are available to the user of the 610A.
They are selected by a slide switch at the back of the instrument,
Normally, current is determined by measuring the voltage drop acr ss
;,‘$I5
put of the voltmeter through the current measuring resistor,
largely eliminates the input drop and increases measuring speed,
particularly on the more sensitive ranges,
the ‘nput resistance may be varied in decade steps from one
10lf
ohms by means of the shunt resistors built into the
ampere, and 4% of full scale from 3 x lo-
or shunted from input to ground, Alternately, on the 10
ampere ranges,
negative feedback can be applied to the in-
- INTRODUCTION
Accuracy is within 2% of full scale
sea e
4
4
This
The 610A measures 0.2 ohm to 1011 ohms with a two-
With a guarded input, its range is extended to 10
volt external supply would further extend the range to 1016 ohms,
Unlike conventional ohmmeters, information is presented on the
same linear scales used for current and volt ge
racy is within 3% of full scale up to 3 x
beyond,
As a dc preamplifier, the 610A has a maximum gain of 1000, obtainable in 9 steps of 0.1,
accuracy is within 1% on all gain steps,
of the gain is assured by a feedback factor in excess of 100 on any
range,
The output is either 10 volts for driving high impedance devices
such as oscilloscopes or pen recorder amplifiers, or 1 ma for
driving low impedance recorders or similar devices.
potentiometer is provided with the 1 ma position for calibrating
recorders. A slide switch next to the output connector permits
selecting the desired output,
0,3, 1, 3, 10, 30, 100, 300, and 1000.
8
10
ohms, within 5%
The continuing stability
erminal
li
ohms,
readings.
A calibration
input,
A lOOO-
Accu-
Gain
0762R
l-1
INTRODUCTION
Red meter scales and a ZERO CENTER position on the METER switch
permit all of the above operations with the zero reference at the
center of the meter dial rather than at the left,
The Model 610A (left) and the
Model 610R (below) have ident-
ical electrical specifications
and performances, The two
models differ only in phys-
ical appearance; the 610A is
for bench use while the 610R
is for rack mounting.
MODEL 610A
0762R
MODEL 610A
SPECIFICATIONS AND DESCRIPTION
SECTION II
SPECIFICATIONS
Ranges :
a.
Voltage: 0.01, 0.03, 0.1, 0.3, 1, 3, 10, 30, and 100
volts full scale,
b,
Current: 3 amperes to lo-l3
3x overlapping ran es,
C.
Ohms :
10 ohms to 10 f 4 ohms full scale on linear lx and
3x overlapping ranges,
d,
Meter scales: Black -
Accuracy:
a.
b,
Voltage:
Current: 3% of full scale from
4% of full scale from 3 x 10-l
C.
Ohms : 3% of full scale from 10 ohms to
of full scale from 3 x 1010 ohms to 10
Resistance Standards:
- SPECIFICATIONS & DESCRIPTION
amperes full scale in lx and
Left zero, 0 to 3 and 0 to 10
- Center zero, -1.5 to 0 to +1,5 and
Red
-5 to 0 to +5.
2% of full scale on all ranges,
to lo-10 amperes,
change slightly in value with age,
Input Impedance:
On the VOLTS position the input impedance is
ohms resistive, shunted by approximately 30 micromicrofarads.
Drift:
Less than 2 millivolts per hour after a 1 hour warm-up,
Recorder Output:
1 milliampere or 10 volts for full scale meter deflection,
selected by a rear panel switch,
Amplifier:
Frequency response is DC to 500 cycles on the most sensitive
range, rising to 10 kc on the least sensitive range.
gain is 1000, Noise is less than 3% (peak to peak) of full
scale,
Line Regulation:
A ten
percent
130 or 200 to 260 volts will cause a change of less than
2 mllllvolts equivalent input,
resistors
may
be expected to
greater
than 1014
Maximum
change in line voltage in the range of 100 to
0563~
2-l
SPECIFICATIONS AND DESCRIPTION
MODEL 610A
Tubes :
Two 5886, two EF86, one 6BH8, two 12AX7, one 12B4A, one OG3,
one OA2, one OB2.
Cabinet:
7-l/4 wide by 11-l/2 high by 13-3/4 deep, Weight 21-114 lbs.
Power Supply:
100 to 130 (or 200
to 260) v,olts, 50 to
60 cycles at approx-
imately 50 watts.
DESCRIPTION
The Keithley Model 610A is a line operated multipurpose dc measur-
ing instrument of extremely wide range, The measuring ranges are
summari,zed below:
VOLTAGE :
10 millivolts to 100 volts full scale, The input imped-
ance is greater than 1014 ohms shunted by approximately 30 micro-
microfarads on the VOLTS position of the RANGE SWITCH,
resistance may be varied from 1011 h
o ms to 1 ohm in decade steps
The input
by rotating the RANGE switch in the AMPERES range marking.
HIGH VOLTAGE WITH ACCESSORIES:
The Model 61024 10~1 divider probe.
extends the measuring range to 1000 volts. The divider resistance
is 1010 ohms and its division accuracy is 1%.
The Model 6103A lOOO:l.divide~ pro& extends the measuring .range to
30 KV.
Its input resistance is 10 ohms and its dzvision accuracy
is 3%.
CURRENT :
to 3 x 10-3
3 amperes to 10’13
amperes
full scale.
amperes the current is measured by measur’ngthe
across a resistor shunted across the input,
From 10
From 3 amperes
-4
amperes, the method above may be used or, by placing the FAST-NOR-
MAL switch on the back panel in the FAST position, negative feed-
back is applied around the shunt resistor, This makes the input
drop negligible and improves speed of response considerably on the
low current ranges.
OHMS :
10 ohms to 1014 ohms full scale,
The linear ohms scale is achieved by measuring the unknown resistor
with a known,
across the sample is thff proportional to the resistance.
ance from 10 ohms to 10
minal method.
constant current flowing through it, The voltage drop
Resist-
ohms full scale is measured by a two ter-
From 1011 to 1014 ohms., use of the GUARD terminal
available at the rear of the instrument is recommended,
DC AMPLIFIER:
The frequency response of the Model 610A as an amplifier is from dc to’ 500 cycles on the 100 millivolt range rising to
10 kc on the 100 volt range.
2-2
The output is either 10 volts or 1
0762R
MODEL 610A
SPECIFICATIONS AND DESCRIPTION
milliampere for fu .ll sea
microammeter position,
,le meter deflection, In the NORMAL micro-
one side of the output is grounded, For
directions pertaining to the use of recorders see Section IV-G.
CURRENT SOURCE: When measuring ohms,
the instrument is designed
to supply a constant current to any device placed across its in-
put
terminals, The magnitude of the current is equal to the reciprocal of the designation on the OHMS segment of the RANGE
switch, Therefore,
the instrument may be used as a current source
for calibration of other instruments if desired.
CONTROLS AND TERMINALS:
The input connector is Gremar Type #6804.
The mating connector is supplied as well as an accessory binding
post
which plugs into the center of the connector, A ground bind-
ing post is mounted on the panel above the input connector.
Front Panel controls are:
RANGE switch,
themeter,
the AMPERES position,
located in the center of the front panel under
This control selects VOLTS, OHMS, or AMPERES. On
a shunt resistor whose value is the reciprocal of the designated range may be used to decrease the
input resistance as well as to measure current.
MULTIPLIER switch, located in the center directly under the
meter, determines the voltage.sensitivity of the dc amplifier,
and sets the voltage range when the RANGE is set on VOLTS. On
OHMS or AMPERES, the setting of this knob multiplied by the
OHMS or AMPERES setting gives the full scale meter range,
ZERO control,
sr the meter,
located to the left of the MULTIPLIER switch
is used to set the meter to zero.
METER switch, at the right under the meter, turns the instru-
menton, determines meter polarity, and permits zero center
operation,
OPERATE switch, located at the bottom right, selects normal
operation or one of the two check positions.
In the ZERO CHECK position, the input terminals are shorted
through 1 megohm,
the RES CHECK position,
standards are measured,
Rear Panel controls are:
FUSE, at the upper right,
ZiijGre fuse;
with 230 volt power use 1 amp fuse,
POWER INPUT, Unless indicated,
volts 50-66 cps.
cuit schematic diagram,
while the amplifier input is shorted. In
the internal high megohm resistance
With 117 volt AC power use 1.5
instrument is wired for 117
For 230 volt operation, consult the cir-
076211
2-3
SPECIFICATIONS AND DESCRIPTION
>lODEL 610A
RECORDER CAL.
Used to calibrate 1 ma. recorders, so their
scale corresponds with the panel meter.
1 >{A - 1OV.
ampere recorders,
In the 1 MA position, OUTPUT will drive 1 milli-
In the 1OV position, the output is 10
volts for full scale panel meter deflection.
OUTPUT connector for external recorders,
NORMAL- FAST,
FAST position,
around the shunt resistor,
This control is locked
in
NORMAL position, In
current measurements are made with feedback
On OfWS, the FAST position is
used when the INPUT GUARD terminal is used,
INPUT
GUARD.
With the NORMAL-FAST switch on FAST, the low
rmpednnce end of the test sample is returned to this terminal
when it is desired to measure the resistance of a guarded
sample.
COARSE ZERO,
If the amplifier is quite badly unbalanced, the
-switch is used to bring the front panel ZERO control
in range.
I
2-4
0762R
MODEL 610A
CIRCUIT DISCUSSION
SECTION III
- CIRCUIT DISCUSSION
The basic element of the Model 610A is a highly accurate, stable
dc voltmeter with a full scale sensitivity of 10 millivolts and
an input impedance greater than 1014 ohms shunted by 30 micro-
microfarads,
ance standards,
Amperes and ohms are measured by the
use
of resist-
The various connections necessary for amperes and
ohms measurements will be discussed following the detailed descrip-
tion of
A.
Refer to DR 11861 D at the rear of the
the
amplifier,
VOLTMETER
manual,
The amplifier proper consists of Vl through V5-A.
VS-B is a Cathode follower
which drives the amplifier
at the same instantaneous
potential as the input signal,
In other words the
neutral or ground terminal
of the amplifier is not
-9
INPUT
0
-
1 ~_ L
A
-- -
* I
AHR
SND.
-
grounded to the chassis
but is attached either directly or through divider
R165 through R171 to then
+
OUTPUT ‘ROVND
output cathode folliower.
Fig,
610-l shows this dia-
gramatically. The ampli-
FIGURE 610-l
is desired to have unity gain,
to the cathode,
To increase the voltage gain, a fraction of the
the amplifier is connected directly
output voltage rather than all of
it
fier
A
is driven by the
cathode follower,
is fed back,
If it
The purpose of this arrangement is to allow the input to accept
relatively large input voltages without use of input dividers,
which are neither stable nor accurate at high impedance.
Conse-
quently, the Model 610A will accept 100 volts without the use of
input dividers, preserving the high input impedance and accuracy
of the amplifier,
Accessory
probes are available for extending
the voltage range at reduced input resistance and accuracy.
Since the amplifier proper is driven by the cathode follower, the
plus and minus 220 volt supplies for the cathode follower are re-
ferred to input ground while the +225 volt and the -85 and -150
volt supplies for the amplifier are referred to amplifier ground
which is “floating”,
In subsequent discussion, reference will be
made to the amplifier ground as “floating ground” and to cathode
follower ground as “output ground”.
0762R
3-1
CIRCUIT DISCUSSION
MODEL 610A
The amplifier input consists of two balanced 5886 electrometer tubes,
The filaments are operated in parallel through a dropping resistor
from the regulated B-plus supply, The control grid of Vl, the active
electrometer tube,
is protected by R123, a ten megohm resistor,
bypassed for high frequencies by ClOl. The control grid of V2,
the “dummy” tube, is returned to floating ground,
The input switch,
SW3, connects the grid of Vl to the input terminal on the OPERATE
position and connects it to ground,
resistor,
on ZERO CHECK,
through the 1 megohm protective
The screen grids of Vl and V2 are returned, in effect, to the cathodes
of V3 and V4 through SW4 (COARSE BALANCE) and R180 (ZERO), The
balance controls function by adjusting the dc voltages of the electro-
meter tube screens, Since the cathode of V3 and V4 are free to
move,
the result is that a negative feedback loop for signals in
phase at the electrometer tubes exists through the cathode circuit
of V3 and V4 back to the screens of Vl and V2.
This connection
stabilizes the plate potential of the input tubes, and causes the
first stage gain to be much greater for signals arriving at the
active tube control grid than spurious signals at both electrometer
tubes,
conductance due to filament temperature changes,
stabilization,
such as variation in the plate supply and changes in trans-
Also due to this
electrometer tube operating points are maintained
even though 10 meg plate load resistors are used to assure a large
voltage gain in this stage, This obviates the need for regulation
of the filaments of subsequent stages,
V3 and V4 form an ordinary differential amplifier and their output
is taken single ended into VS-A,
V6-A drives the output cathode
follower,
The,.voltmeter sensitivity is determined by the fraction of the cathode
follower voltage fed back via the divider, R165 through R171. 10
volts appears at the VS-B cathode for full scale meter deflection
for the ranges from 10 millivolts through 10 volts, On the 30 and
100 volt ranges, 30 and 100 volts respectively are fed directly
back to floating ground. R161 is the meter multiplier resistor
from 10 millivolts to 10 volts,
R162 and R163
are
used.
On the 30 and 100 volt ranges,
The OUTPUT is derived directly from the 6BH8 cathode except on the
30 and 100 volt ranges,
the output switch is set at 10
with R177 to attenuate the output to 10 volts.
is set at 1 ma,
these resistors in combination with R164 and R160
where R158 and R159 are interposed, If
V, R158 and R159 form~a divider
If the output switch
are used to provide enough series resistance so that 1 milliampere
flows into the recorder terminals. R164 and R160 calibrate the
recorder on all
ranges.
The feedbacks loop is stabilized against oscillation by Cl02 and
Cl03 together with R172 through R176.
Insertion of R172 through
R176 in the cathode of VS-A, or the omission of a resistor by the
range switch, determines the loop gain, The gain is kept high enough
so that there is a feedback factor of at least 100 on all ranges,
but the gain is not allowed to become high enough to cause oscilla-
3-2
076213
MODEL 610A
CIRCUIT DISCUSSION
tion.
Cl02 and Cl03 provide a 6 db per octave dominant lag cut-
off characteristic,
B.
AMMETER
Grid current of the input electrometer tube fixes the minimum cur-
The Model 610A grid current will usually
~?:e::a~h~~Y2b~ ~~“sYr~~~eres On low current ranges the grid
current will be apparent and rniy be balanced out with Ihe ZERO control or subtracted from the final reading,
(1) Shunt Resistor Method (NOWIAL)
In the normal operating
connection as shown in
Fig, 610-2A, current is
measured by placing a
resistor across the input
terminals and measuring
the voltage drop, Cur-
;;“I? ;;;;&a;;;r;; lco
measured by this method
since the range switch
selects resistors r nging
from one ohm to 1Ola ohms
in decade steps,
The volt
age drop is selected by
the MULTIPLIER switch; the
setting is the input voltage drop for full-scale
FIGURE 610-2A
meter deflection.
(2) Feedback Method (FAST)
In
the voltmeter discus-
sion above, floating grounc
has been driven by the
cathode follower and out-
put ground has been
con-
nected to the low impedance side of the input
connector,
connect ion,
In the FAST
shown in Fig.
610-2B, the amplifier
ground is connected to
the low impedance side
of the input; the cathode
follower ground floats,
z
FIGURE 610-2B
and negative feedback
is applied through the
shunt resistor,
In the Model 610A, it is possible to use this connection with currents
of 100 microamperes or less,
To change the connection, remove the
lock from the NORMAL-FAST switch at the bottom of the rear panel and
change it to the FAST position, The advantages of this connection
are :
0762R
3-3
CIRCUIT DISCUSSION MODEL 610A
a,
b.
If Fig, 610-2B is again consulted, it will be seen that this connection
converts the 610A into an operational amplifier with a resistor from
the output to the input. Therefore, the following cautions apply:
a.
b.
C.
The effect of input capacity is largely neutralized, that
the time constant of the input and cable capacity and
is,
the shunt resistor used will be decreased at least 100
times as compared to the NORMAL connection, corresponding
to a loo-fold increase in response speed,
The input drop Will be reduced at least 100 times,
The input cannot be shorted since this will remove the
feedback,
The internal impedance of the current ,source being measured
should not be less than about one-tenth of the value of
the feedback resistor used for measurement,
This connection should not be used for measuring the leakage current of capacitors since the connection of a capacitor to the input causes the circuit to be transformed
into a differentiator with the resultant extreme sensitivity
to ver~y small voltage transients, For this measurement
the NORMAL should be used,
d.
C.
age and a large resistor of known value,
the unknown resistor is of the order of 1% of the total voltage,
the curren
103 and 10
100 volt’supply with the appropriate dropping resistor as illustrated
in Fig, 610-3, For example,
voltage drop across a one
this value can be read on the 10 millivolt range of the
OHMMETER
1.
Do not attempt to use the FAST connection for currents
exceeding 100 microamperes.
Two Terminal Method
The ?lodel 610A employs a
linear scale to provide a
megohmmeter of high accur-
acy.
is achieved by supplying
IOOV I
=
FIGURE 610-3
can be considered constant,
s:
ranges, the current is supplied in this manner from a
METER
with a current of one milliampere, the
ohm resistor will be one millivolt,
a constant current to the
sample and measuring the
voltage drop across it,
One method is shown in Fig,
610-3,
The constant current source
can consist of a high volt-
As long as the drop across
In the Model 610A on
The linear ohms scale
the
610A,
Thus,
I
3-4
0762R
MODEL 610A
CIRCUIT DISCUSSION
-
,.E
h
I ,
oh
Rs
On the 10’ range
and
higher,
a second method is used to
obtain a constant current.
This is illustrated in Fig.
610-4.
The ground connections
are in the NORMAL position,
RI
that is,
is driven and the cathode-
the amplifier ground
follower ground is attached
The
FTGURE 610-4
to the input ground.
voltage source is only one
volt L
However,
it is attached
between floating ground and the grid of the voltmeter while, as
before, the test sample is attached between input ground and the
voltmeter grid,
Since feedback to the amplifier ground keeps it
at virtually the same potential as the input grid regardless of
the input voltage,
cannot change, Therefore,
regardless of the input voltage,
the voltage across the current source resistor
this arrangement provides a true source
Thus,
resistances may be measured
using any voltmeter range on the lo5 to 1012 ohmyeter ranges as
opposed to the limit of 1 volt maximum on the 10
to 104 ohmmeter
ranges,
2,
Ohms measurement using
GUARD
terminal
There are two disadvantages with the method just outlined:
ar
When measuring resistances greater than 1011 ohms, input capacity causes the meter reading to be annoyingly
slow,
b.
If it is desired to use large voltages across the sample,
this same voltage will appear across the input insulation of the electrometer and the input insulation will
contribute error to the reading because of the current
also flowing in it,
For these reasons a second connection for measuring ohms is provided.
Ru
The switch at the rear of
the instrument is moved from
NORMAL to FAST and the low
impedance end of the resistance sample is connected to
the GUARD terminal. Fig.
1
UARO
610-S shows the arrangement.
Now, as with measuring amperes
with the FAST method, the
amplifier ground is attached
to the input ground and the
cathode-follower ground is
I
I
floating.
feedback is applied through
The result is that
the unknown resistance to
FIGURE 610-5
reduce the slowing effect of
0762R
3-5
CIRCUIT DISCUSSION
MODEL 610A
instrument input capacity,
Also, since the potential across the input
terminal is small, the leakage error is reduced.
3.
With the constant current method of measuring
Use of External Voltage Supply
resistance,
the voltage across the unknown may not be arbitrarily selected, and the time
of measuring capacitor leakage tends to be long, since constant-current
charging is slower than the exponential charge available with an RC
circuit,
Due to these facts, it may be desirable to use an external voltage
supply and measure the leakage current on the AMPERES scale (NORMAL
operation).
The unknown is connected between
the input terminal of the electro-
meter and the source of voltage.
This is shown in Fig, 610-6. If
the applied voltage is large com-
pared to the voltage drop across
the electrometer (so that the volt-
EXTERNAL
VOLTME
age across the sample is substantially the applied voltage) the resistance is simply equal to the
voltage applied divided by the cur-
FIGURE 610-6
rent
measured, If the voltage drop
is an appreciable fraction of the
applied voltage, the resistance equals the voltage applied minus
the input drop divided by the current measured,
necessary
to correct
for the input drop of the electrometer due to
It will be rarely
the excellent voltage sensitivity of the Model 610A.
It is advisable to use the NORMAL micro-microammeter connection for
the measurement of leakage resistance of capacitors in this manner,
since instability is likely to occur using the FAST connection.
However, in cases where the capacity shunted across the sample is
small,
it will be possible to realize a considerable increase in
speed of response by utilizing the FAST connection.
Some precaustions are recommended when testing capacitors,
Be sure
that capacitors have discharged before removing from test circuit,
With the 610A input switch
on
ZERO CHECK, the input is shorted to
ground through 1 megohm, providing a discharge path for the capacitor, The reading time may be shortened if the capacitor is allowed
to charge through a low impedance position on the AMPERE switch before the appropriate measuring resistor is inserted in the circuit,
It should be further noted that capacitor measurement is likely to
be a slow process in any case due to the fact that it may take considerable time for the molecular orientation of the dielectric to
take
place
at the testing potential,
It may take minutes or even
hours in some cases to achieve a stable reading,
MODEL 610A
CIRCUIT DISCUSSION
D.
The resistance standards used in the Model 610A have been described
in th specification section,
to 10
life of the instrument, The high megohm resistors are correct to
2% when installed!
nominal value,
are likely to remain within specifications for three to six years
after the instrument is delivered,
However, to determine the accuracy of these resistors, a resistance
check position is provided on the input switch.
scale on the 0,l position for the
position for the 109 ohm resistor,
STANDARD RESISTOR CHECK
5
ohms can be expected to retain a 1% accuracy throughout the
and will usually be between 1% and 2% above the
Since they always decrease in value with time, they
FIGURE 610-7
In general the resistors from 1 ohm
The method used in checking the
resistors is outlined in Fig,
610-7,
the standard manner except that
the input switch is turned to RE
CHECK,
ohm resistor is
in ut.
Pl
10
supply current through this res’
from 10 volts.
position on the OHMS segment of
the RANGE switch is used, the meter
should read full scale on the .Ol
position of the MULTIPLIER.
resi3
10
The ohmmeter is used in
In th’is position a 1%
pla ed across the
In turn, 10
ohm resistors a:e use: to
ndingly, the reading is full
ohm resistor and the 1.0
5
Thus,
lOlo and
if the lOi
10
Cor-
2
tor
E.
The negative regulator consists of cascaded voltage regulator tubes
Vll and VlO.
for the negative return of the second amplifier stage and reference
for the positive supply, The maximum current supplied by this regulator combination is about 2.5 milliamperes so that the regulator
tubes are able to operate satisfactorily over the 100 to 130 volt
range of line voltage,
potential for the amplifier interstage dividers.
The positive 225 volt regulator is a three tube regular circuit
consisting of V8, the series tube, and V6 and V7 which form the
feedback amplifier,
to 130 volts and is largely responsible’for the extreme freedom
from line transients which the Model 610~4 exhibits.
0762R
Tf-IE REGULATED POI\‘ER SUPPLIES
This combination provides a well-regulated supply
Vll, type OA2,
This circuit operates satisfactorily from 100
supplies a minus 150 volt
3-7
iMODEL 61OA
OPERATION
SECTION IV - OPERATION
A,
PREPARING THE INSTRUMENT FOR OPERATION
1,
Connect to power line of proper voltage and frequency,
Unless otherwise indicated at rear of instrument, the
Model 610A is wired for 100 to 130 volts 50 to 60 cps,
If it is desired to operate on 200 to 260 volts 50 to
60 cps, consult DR 11861 D at rear of the manual for
instructions,
2.
3.
Set controls as follows:
MULTIPLIER:
RANGE SWITCH:
OPERATE SWITCH:
INPUT TERMINAL:
100
VOLTS
ZERO CHECK
Shield with cap.
Turn the METER switch to meter +,
come to zero in approximately 30 seconds. Final stability
within drift specifications will not be achieved for 1
hour,
4.
Rotate the MULTIPLIER switch toward the high sensitivity
end, adjusting ZERO as required, If it is impossible
to zero the meter with the front panel ZERO control, use
COARSE BAL control on rear panel to bring the instrument
within range of the ZERO control,
The instrument should
5.
B.
Connect leads as required for measurement,
pedance is involved,
the input should be shielded using
a coaxial connection or shielded enclosure,
If high im-
The various
accessories for the Model 610A may be used,
If the impedance is low and leads can be kept short, the
“,in;;;j post adapter furnished with the instrument may
.
The Keithley Model 6101A Shielded Test Probe will suffice
for most measurements,
MEASURING VOLTAGE
Place RANGE switch at VOLTS, Turn MULTIPLIER switch to
expected sensitivity and check meter zero,
switch up to OPERATE and read,
If the sensitivity of
Move OPERATE
the instrument is increased, recheck the zero setting.
For voltages greater than 100 volts, use the Mod-l 610ZA
1O:l Divider Probe, or the Model 6103A 1OOO:l Divider Probe
and measure as above,
076211
4-1
OPERATION
MODEL 610A
C.
MEASURING CURRENT
1,
Turn RANGE switch to desired AMPERES range,
NORMAL method (3 amperes to 10-13 amperes full scale),
Make sure the switch
at the rear of the instrument is on the NORMAL position, Connect
current source to input,
The product of the reading on the
RANGE switch and ~the MULTIPLIER gives the full scale range.
Check zero first with OPERATE switch and then read unknown
current,
The full scale voltage drop across the instrument
is the setting of the MULTIPLIER,
2.
FAST method (10m4 to IO-13 amperes full scale),
Proceed as above, except move the FAST-NORMAL switch at the rear
of the instrument to the FAST position, The input drop is now
negligible and the speed of response is increased approximately
100 times,
a.
However, observe the following cautions:
Use only the input switch to check zero; DO NOT SHORT
INPUT,
b,
The low side of the output is no longer grounded,
Therefore,
if the instrument is being used with an
output recorder the recorder must not be grounded
to the case of the 610A.
D,
C.
Do not use this position for the measurement of capacitor leakages,
MEASURING RESISTANCE
1,
NORMAL method (10 ohms to 1011 ohms full scale),
Turn RANGE switch to desired OHMS range, Make sure that NORMALFAST switch is in the NORMAL position,,
Connect resistance sample to be measured only after OPERATE
switch has been moved to ZERO CHECK,
Do not open-circuit instru-
ment when on OHMS, since the input will develop a large volt-
age due to its constant current characteristic,
However, if
the sample is first connected and then the OPERATE switch is
moved to OPERATE, the full scale input voltage will be the
setting of the MULTIPLIER,
Before reading OHMS,
of the unknown resistance,
the RANGE switch,
potentials,
if desired,
turn RANGE switch to the approximate range
By manipulating
the
MULTIPLIER and
the sample can be tested at a number of test
The full-scale ohms range is the RANGE switch setting times
the MULTIPLIER,
4-2
0762R
MODEL 610A OPERATION
This two terminal method is the simplest and will work quite
satisfactorily up to about 1011 ohms,
than 1011 ohms,
it is desirable to employ a GUARD connection
At resistances greater
both to speed up the response of the instrument and to nullify
the error of leakage across the electrometer input insulation,
2.
GUARDED method (loll to 1014 ohms full scale),
Proceed as with the two terminal method with the exception
that the sample is connected between the INPUT terminal and
the GUARD terminal on the rear panel, the FAST-NORMAL switch
must be set at FAST,
3.
EXTERNAL VOLTAGE method,
Any external voltage may be used.
The unknown is connected between the test potential and the
INPUT terminal of the electrometer. The current is then
measured,
using the NORMAL or FAST method, and the resistance
calculated,
Proceed as follows:
a,
b.
Turn input switch to ZERO CHECK,
Connect unknown between INPUT terminal and source
of potential,
A switch should be connected in the
high voltage line so that when the sample is disconnected from the potential, the low impedance end of
the sample is grounded.
C.
d.
FAST-NORMAL switch should be at NORMAL,
Apply potential to sample before switching to OPERATE. Start the RANGE switch at low current sensitiv-
ities and advance the sensitivity until a reading
is obtained,
If the potential applied is at least 100 times the
full scale ammeter drop (MULTIPLIER setting), the
resistance is equal to:
POTENTIAL APPLIED
If the potential applied is not large compared to the
ammeter drop, the resistance is equal to:
POTENTIAL APPLIED - INPUT DROP (VOLTS)
Cm READING
e. If it is possible to operate on FAST micro-microam-
me,ter, the input drop need not be considered in the
calculation.
0762R
4-3
OPERATION
MODEL 610A
E.
F.
G.
The output of the Model 610A will drive one-millivampere recorders
and servo rebalance recorders,
ments such as pen recorder amplifiers and oscilloscopes.
INTERNAL RESISTOR CHECK
1.
to OHMS x log,
to RES CHECK,
x 109,
2.
be .1 volt.
3.
be ,Ol volts.
INTERNAL VOLTAGE CHECK
The internal 225-volt and lOO-volt supplies are used to test
resistance samples and therefore,
To check these supplies see Section VI - MAINTENANCE.
USING EXTERNAL INDICATORS
To check log:
To check lOlo: Turn MULTIPLIER to .I or .3,
To check loll: Turn MULTIPLIER to .Ol or .03.
Move input switch to ZERO CHECK, RANGE switch
Turn MULTIPLIER to 1.0 or 3.0. Move input switch
If reading is exactly one volt, resistor is 1.00
should be checked periodically.
as well as higher impedance instru-
Reading should
Reading should
1,
Angua, General Electric,
nect to output connector at rear of instrument, pin 1 is the
positive terminal,
put is approximately 1 ma for full scale meter deflection on
any range and can be made exactly 1,00 ma,
range such as 100 millivolts full scale, where zero control has
enough latitude,
scale, Then adjust RECORDER CAL at the rear until the recorder
also reads full scale, Next check the zero of the recorder and
the panel meter and repeat full scale calibration, The meter
polarity switch does not reverse the recorder output,
2.
ition, there is enough latitude in the RECORDER CAL pot so that
even if the recorder terminals are short circuited, exactly
1 milliampere can be made to flow at full scale deflection of
the panel meter, Therefore, for servo rebalance recorders, place
a resistor across the output terminals equal to 1 ohm per milli-
volt of span and adjust RECORDER CAL to make sensitivity equal
to full scale meter deflection,
volt recorder place 50 ohms across output terminals before connecting recorder,
3.
set output switch at the 1Ov position,
for full scale meter deflection on any range,
For use with one-milliampere instruments such as Esterline
and Texas Instrument Rectiriter: Con-
Place output switch at 1 MA position,
Turn to a voltage
and adjust ZERO until panel meter reads full
For use with servo rebalance recorders: On the 1 MA pos-
For example, with a 50 milli-
For use with oscilloscopes and pen recorder amplifiers,
Output is now 10 volts
Out-
4-4
0762R
MODEL 610A
The frequency response is dc to 500 cycles on the 10 millivolt range rising to 10 kc on the 10, 30 and 100 volt ranges,
The maximum amplitude which can be delivered by the amplifier
is approximately 10 volts peak to peak,
load across the output terminals in this mode of operation is
one megohm.
With the FAST-NORMAL switch at the rear of the instrument in
the NOR?IAL position,
to the case of the instrument,
neither side is grounded,
experienced using oscilloscopes and pen amplifiers with the
610A in NORMAL operation,
the FAST position,
mon ground between the pen writer or the oscilloscope and the
Model 610A case,
OPERATION
Maximum permissible
the negative side of the output is grounded
However,
Therefore,
However,
care must be taken that there is no com-
if it is desired to use
in the FAST position
no difficulty will be
H.
MISCELLANEOUS APPLICATIONS
CURRENT INTEGRATOR:
for small currents such as cyclotron and mass spectrometer beam
currents, since it is basically an operational amplifier with
electrometer input when the FAST-NORMAL switch at the rear is
placed in the FAST position,
To integrate current connect a polystyrene capacitor of suitable value between the GUARD terminal and the input, The RANGE
switch is set at VOLTS so that there is no resistance placed
across the capacity,
be seen that the standard resistor has been replaced by a capacitor and the 610A is now an integrator, The charge on the
capacitor in coulombs is simply the product of the capacitor
value chosen (in farads) and the setting of the MULTIPLIER
switch (in volts), If it is desired that a time constant he
introduced into the integrating circuit, the appropriate shunt
resistor may be selected by the RANGE switch,
Practically it
a grounded can
made by a simp
put terminal should be made by means of a coaxial connection
to one side of a “tee” adapter,
the other side of the “tee”.
is suggested that the capacitor be enclosed in
ie unshielded lead,
The Model 610A may he used as an integrator
Then if Fig,
The connection to the GUARD terminal may he
610-2B is consulted, it can
The connection to the in-
The current input is made to
The following procedure is suggested:
ZERO CHECK, thus removing the charge from the capacitor and
shorting the input, Zero if necessary, Return to OPERATE,
If the integration is to take place over a long period of time,
it is sugg~ested that the instrument he used on the one volt
range or higher so that zero drift and grid current will not
he factors.
0762R
Move input switch to
4-5
OPERATION MODEL 610A
Move OPERATE switch to ZERO CHECK and RANGE switch to OHMS.
The current that is supplied on each range is the reciprocal
of the OHMS setting,
MULTIPLIER switch,
the amplifier should be in balance,
balance the amplifier on the
switch,
and is not affected by the setting of the
However, for the current to be accurate,
It will be sufficient to
.l volt position of the MULTIPLIER
I.
STATIC CHARGE MEASUREMENTS:
RANGE switch placed on VOLTS.
haps placed at 10 or 30 volts full scale, The charged object
is then brought near the uncovered,
of the 610A.
the instrument, a voltage will be induced on the input terminals
and can be read on the panel meter,
be checked frequently since accumulation of charge due to the
electrometer tube grid current will cause a slow drift of input
voltage.
Connecting a capacitor across the input reduces the drift due
to grid current and also the sensitivity to cherge,
connected to the INPUT terminal which increases the capacitance
between the INPUT terminal and the charged object will increase
the sensitivity to charges,
ZERO CENTER OPERATION
1.n some applications,
voltages of either polarity near zero, it may be desirable to
use the ZERO CENTER position on the METER switch,
position, operation is just the same as for left-zero (normal),
except that for zero input voltage or current, the meter pointer
is at center scale,
Depending on the distance between the charge and
such as null indication or in measuring
The instrument is zeroed and the
The voltage sensitivity is per-
unshielded input connector
The instrument zero should
An electrode
On this
4-6
The ZERO CENTER control on the inside chassis is used to set
the meter pointer to zero for zero center operation,
require only infrequent attention,
It should
076ZR
MODEL 610A
SECTIOh’ V - ACCESSORIES
MODEL 6101A ACCESSORY PROBE:
The Model 6101A probe consists of an input connector, 3 feet of
low noise cable and a shielded probe head.
allow convenient connection to the electrometer input.
MODEL 6102A -1O:l DIVIDER PROBE:
The Model 6102A divider probe is intended forgeneral purpose instru-
ments where an extension of the upper voltage range of the 610A is
desired,
input resistance is lOlo ohms, The probe is supplied with a mating connector and 3 feet of cable.
The division ratio is 1O:l correct to 1% and the probe
Its purpose is to
ACCESSORIES
MODEL 6103A -
The Model 6103A probe is intended for very high voltage measurements
at high impedance,
the probe input resistance is 1012 ohms,
with a mating connector and 3 feet of cable,
MODEL 6104 TEST ADAPTER:
The Model 6104 Test Adapter is intended for use in making measure-
ments wherein complete shielding of the component under test is re-
quired,
or a test requiring an external voltage source,
External terminals are provided for either grounded tests,
1OOO:l DIVIDER PROBE:
The division ratio is 1OOO:l correct to 3% and
The probe is supplied,
0762R
5-l
QODEL 610A
blAINTENAhCE
SECTION VI
- MAINTEhANCE
No periodic maintenance is required other than checking the accuracy
of the polarization potentials and the high megohm resistors as provided for by the front panel controls.
teries,
The method of performing these checks is outlined in Sectio:
There are no internal bat-
IV part E and F,
The calibration of the voltmeter is set by R179 located on the vertical chassis carrying the majority of the tubes,
the factory and should not require adjustment,
This is set at
If recalibration
is performed, an accurate voltage source should be used,
A .
The circuit is completely described in Section III.
TROUBLE SHOOTING
Study of that
section will facilitate any trouble shooting,
The most
voltage range, with the input shorted,
the meter pointer to zero,
usual
trouble encountered is that on the most sensitive
it is not possible to bring
However, before assuming that the instru
ment is at fault make sure that resetting the COARSE BAL control at
the rear of the instrument will not bring the instrument back into
balance. If this does not work remove the instrument case and if
necessary the bottom plate just below the input compartment to gain
access to all circuitry,
Follow this procedure:
1, Check for presence of regulated B-plus voltage by switch-
ing to meter + and checking at pin 6 of V-4 for +225V. If this
voltage is not correct consult section following on servicing
regulated power supply,
2.
If correct voltage is present, check the plus and minus
220 volt supplies which supply the output cathode follower,
The plus voltage is present on pin 3 of V5,
‘The minus
voltage
may be obtained from the bottom of the 30K cathode resistor
of vs-B. It is a 10 watt power resistor located on the metal
chassis next to the rectifier stacks.
If this voltage is not
correct consult the schematic and trouble shoot the supply in
the usual manner.
7
. .
If no defects are found so far, Froceed by shorting float-
ing ground to output ground to remove the negative feedback.
This is most conveniently accomplished by shorting the two
ends of the FAST-NORMAL switch on the rear panel,
In this
condition ti:e instrument will become very sensitive and in
operating the ZERO control,
to !lold on scale.
!iowever,
the peter will be very difficult
the indication that the circuit
is operating satisfactorily is that it is possible to swing
the voltage through the correct opernting point as indicated
on the voltege-resista,nce dingran.
Now :\lith the :.ItiLTII‘LIER nt .Ol volts, proceed to chock the
0762R
operatin: points or t!lc tube electrodes.
6-1
\IODEL 61 OA
Regardless of the condition of the amplifier balance, the filament or cathode, and screen potentials should be reasonably
close to the values on the circuit diagram, The plate and grid
potentials will, however,
control,
the correct value it may be assumed that the stage is working,
Proceed in this manner until the point is found where the voltage cannot be swung through the value marked on the diagram.
At this point it will be relatively easy to find the fault,
First check the tube involved and then check the components.
Trouble shooting the regulated supplies:
However, if it is possible to swing the voltage through
depend on the setting of the ZERO
::.AIliTENA!L’CE
1.
is referenced to the negative supply, If the dc voltages seem
correct ,and the trouble persists,,
which would indicate a bad rectifier or filter capacitor,
2.
unregulated supply voltage in the same way,
3.
components of the regulator circuit (V-6, V-7, V-8) for defects.
?liscellaneous troubles:
I
Excessive grid Defective electrometer
I
Excessive drift
Check the minus supply first since the positive supply
If the negative voltages are correct, then check the positive
If the above voltages are correct, check the tubes and
Trouble
current tube with matched set
I
Excessive micro-
phonics
Instrument does
not zero,
check for excessive ripple
I
Power supply not regu- See section above
lating
Defective electrometer
tube with matched set
See section above
Cause
I
Replace Vl and V2
Replace Vl and V2
See s,ection above
Remedy
1
I
The proper method of inserting electrometer tubes is shown in the
voltage resistance diagram,
base where the leads emerge with the fingers,
B.
Three methods of calibrating the 100 volt and 22.5 volt supplies are
possible.
6-2
RECALIBRATING POWER SUPPLIES
1.
precision resistor used is added to the error of the instrument
as stated on page II-l.
This, method is the least accurate since the error of the
When inserting do not touch the glass
0762R
MODEL 610A MAINTENANCE
a,
With the MUL
on OHMS x
the input,
full scale, If not,
control
until a full scale reading is obtained,
b, For the 27.5 volt supply!
IPLIER switch on 1 and RANGE switch
1
10
connect a 10K precision resistor to
On OPERATE, the meter should be near
adjust the internal 100 volt
the MULTIPLIER switch remains at 1 and RANGE switch is moved to OHMS x 105,
Now a precision 1OOK resistor is placed across the
input and the 225 volt control adjusted until a full
scale reading is obtained.
225 volt supply! check the 10 , 10
T8 furr8era:;e;;lIh;e-
sistors as mentloned in Section IV-D’to see if
proper readings are obtained,
2.
pedance voltmeter,
The next method requires the use of an accurate high im-
such as the Keithley Model 660 Guarded Differ
ential Voltmeter, accuracy .02%. The accuracy of the 610A
will then be the 610A specification value stated on page 2-l
plus *OS%.
a.
Place the RANGE switch on VOLTS, the MULTIPLIER
switch on 1 and with the cover off, take a reading
from the right terminal (two leads) of the 100 volt
adjust
pot
to ground, If not at 100, set to 100.
b.
For the 225 volt supply, a reading is taken at the
junction of resistors R125 and R126, located in the
input compartment just above the operate switch.
At this point the voltage should be 1,O volt,
the Set 225 volt control to get 1 volt,
The 225
Use
voltage is a nominal reading, while the 1,O volt
calibration is taken from a voltage divider and should
be accurately set.
3, The last and most accurate way is to send the instrument
back to the factory for calibration,
Here all the proper equipment is available to check and calibrate the Model 610A electrometer, Experienced techniciars perform all work on the instruments to bring them within specifications,
6-3
MODEL 610A
Circuit
Desig.
Description
REPLACEABLE PARTS LIST
Part No,
Cl01
Cl02
Cl03
Cl04
Cl05
Cl06
Cl07
Cl08
Cl09
c301
C302
c303
c304
c305
C306
c307
C308
c309
c310
Capacitor,
Capacitor,
Capacitor,
Capacitor,
Capacitor,
Capacitor,
Capacitor,
Canacitor.
Capacitor;
ceramic disc,
ceramic disc,
ceramic disc,
ceramic disc,
ceramic disc,
ceramic disc,
ceramic disc,
ceramic disc.
ceramic
disc; 100 mmf;
100 mmf, 600 VDCW
.0068 mfd, 600 VDCW
.006&l mfd, 600 VDCW
100 mmf, 600 VDCW
100 mmf, 600 VDCW
47 mmf, 600 VDCW
47 mmf, 600 VDCW
.02 mfd. 600 VDCW
Capacitor, tubular, electrolytic,
350 VDCW
Capacitor, tubular, electrolytic,
350 VDCW
Capacitor, tubular, electrolytic,
600 VDCW
Capacitor, tubular, electrolytic,
450 VDCW
Capacitor,
ceramic
disc, ,02 mfd,
Capacitor, ceramic disc, .02 mfd,
Capacitor,
tubular, electrolytic,
600 VDCW
Capacitor,
ceramic
disc, .02 mfd,
Ca acitor, f tubular, electrolytic,
50 VDCW
Capacitor, ceramic disc, 220 mmf,
600 VDCW
40 mfd,
40 mfd,
20 mfd,
20 mfd,
600 VDCW
600 VDCW
20 mfd,
600 VDCW
20 mfd,
600 VDCW
c22-100
C22-.0068
C22-.0068
c22-100
c22-100
C22-47
C22-47
c22-.02
c22-100
C23-40
C23-40
c35-20
C8-2OL
c22-,02
C22-.02
C35-20
c22-.02
CB-2OL
c22-220
c311
Dl
D2
Capacitor, ceramic disc, ,02 mfd,
Diode,
Diode, Silicon,
Silicon, 1~645. TEXTS Instruments
lN645,
‘Texas instruments
600 VDCW
c22-,02
RF14
RF14
Fl Fuse, l-1/2A, 3AG (llov), Fuse, lA, 3AG (220v)FUE-FU7
M Meter, Panel, O-200UA
RlOl
R102
R103
R104
R105
R106
R107
R108
R109
RllO
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
wirewound, 1 ohm, l%, 10 w
wirewound, 10 ohm, l%, 10 w
wirewound, 100 ohm, l%, 10 w
deposited.carbon, lK, l%, l/2 w
deposited carbon, lOK, l%, l/2 w
deposited carbon,
deposited carbon,
deposited carbon,
deposited carbon,
hi-meg, 109 ohm
IOOK, l%, l/2 w
lM, l%, l/2 w
IOM, l%, 1 w
lOOM, l%, 2 w
ME15
R34-1
R34-10
R34-100
R12-1K
R12-10K
R12-100K
R12-IM
R13-10M
R14-100M
R20-109
0464R
6-5
REPLACEABLE PARTS LIST
I
Circuit
Desig,
Description
MODEL 610A
Part No,
Rlll
R112
Rll6
R117
R118
R119
R120
R121
R122
R123
R124
R125
R126
R127 Resistor,
R128 Resistor,
RI29 Resistor,
R130 Resistor,
R131
R132
R133
R134
R135
Resistor,
Resistor, hi-meg, 1011 ohm
Resistor, deposited carbon, lOOM, I%, 2 w
Resistor, deposited carbon, lM, I%, l/2 w
Resistor,
Resistor,
Resistor, deposited carbon, lOOK, l%, l/2 w
Potentiometer, wirewound, 15K
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
hi-meg, 1010 ohm
deposited carbon, lM, l%, l/2 w
composition, 470 ohm, 5%, l/2 w
composition, 47K, 5%, l/2 w
composition, IOM, lo%, l/2 w
deposited carbon, 100 ohm, l%, l/2 w R12-100
deposited carbon, 900 ohm, l%, l/2 w Rlt-900
deposited carbon, 9K, l%, l/2 w
deposited carbon, 215K, l%, 1
wirewound, 135 ohm, l%, l/2 w
power, 12K, 3%, 25 w
deposited carbon, 33,3K, l%, l/2 w
deposited carbon, 20K, l%, l/2 w
deposited carbon, SK, l%, l/2 w
deposited carbon, 5K, l%, l/2 w
deposited carbon, SK, l%, l/2 w
deposited carbon, SK, l%, l/2 w
w
R20-1010
R20-1011
R14-100M
R12-IM
R12-1M
R19-470
R12-100K
RP3-15K
R19-47K
Rl- IOM
R12-9K
R13-215K
R18-10-135
R30-12K
R12-33.3K
R12-20K
R12-5K
R12-5K
R12-SK
R12-SK
R136
R137
R138
R139
R140
R141
RI42
R143
R144
R145
R146
R147
R148
R149
R150
R151
R152
R153
R154
R155
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
deposited carbon, SK, l%, l/2 w
deposited carbon, 5K, l%, l/2 w
deposited carbon, 20K, l%, l/2 w
deposited carbon, lK, l%, l/2 w
deposited carbon, 200 ohms, l%, l/2
deposited carbon, lK, l%, l/2 w
deposited carbon, lOM, l%, 1 w
deposited carbon, IOM, l%, 1 w
composition, lOOK, 5%, l/2 w
composition, lOOK, 5%, l/2 w
deposited carbon, IOOK, l%, l/2 w
deposited carbon, lM, l%, l/2 w
deposited carbon, l.SM, I%, l/2 w
composition,
composition,
composition,
composition,
composition,
composition, 330K, 5%, l/2 w
wirewound, 30K, lo%,, 10 w
330K, 5%, l/2 w
lK, 5%, i/2 w
47K, 596, l/2 w
IOOK, 5%, 2 w
390K, 5%, l/2 w
R12-SK
R12-SK
Rl2-20K
R12-1K
wR12-200
R12-1K
R13-10M
R13-10M
R19-100K
R19-100K
R12-100K
R12-1M
R12-1.5M
R19-330K
R19-150K
R19-47K
R33-120K
R19-390K
R19-330K
RS-30K
6-6
076217
MODEL 610A
Circuit
Desig.
Description
REPLACEABLE PARTS LIST
Part lu‘o.
R156
R157
R158
Ri59
R160
R161
R162
R163
R164
R165
R166
R167
R168
R169
R170
R171
R172
I~173
R174
R175
R176
R177
R178
R179
R180
Resistor,
Potentiometer, carbon, 5OOK, 10%
Resistor,
Resistor, deposited carbon, 70K, l%, l/2 w
Potentiometer, wirewound, SK
Resistor,
Resistor,
Resistor, deposited carbon, 319K, l%, l/2 w
Resistor,
Resistor,
Resistor, deposited carbon, 2K, l%, l/2 w
Resistor, deposited carbon, 700 ohm, l%, 1/2w R12-700
Resistor, deposited carbon, 200 ohms, l%, 1/2wR12-200
Resistor,
Resistor, deposited carbon, 20 ohm, l%, l/21< R12-20
Resistor, deposited carbon, 9.67 ohm, l%, @w R12-9.67
Resistor,
Resistor, Rl-2.2K
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Potentiometer, wirewound, 15K
Potentiometer, 10K
deposited carbon, 800K, l%, l/2 w
deposited carbon, 20K, l%, l/2 w
deposited carbon, 45,5K, l%, l/2 w R12-45.5K
deposited carbon, 136K, l%, l/2 w
deposited carbon, 6K, l%, l/2 w
deposited carbon, 7K, l%, l/2 w
deposited carbon, 70 ohm, I%, 1/2w R12-70
composition, lK, lo%, l/2 w
composition, 2,2K, lo%, l/2 w
composition, 4,7K, lo%, l/2 w
composition, lOK, lo%, l/2 w
composition, 33K, lo%, l/2 w
deposited carbon, lOK, lpi, l/2 w
deposited carbon, 3K, l%, l/2 w
RlZ-800K
RP7-3
R12-20K
R12-70K
RP3-SK
R12-136K
R12-319K
R12-6K
RlZ-7K
R12-2K
Rl-1K
Rl-4,7K
Rl-1OK
Rl-33K
RlZ-1OK
R12-3K
RP3-15K
RP4-1OK
R181
RlS2
R183
R301
R302
R303
R304
R305
R306
R307
R308
R309
R310
R311
R312
R313
R314
R315
R316
01.63~
Resistor, deposited carbon, 22OK, I%, l/2 w
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor,
Resistor, deposited carbon, 2M, l%, l/2 w
Potentiometer, carbon, lOOK, 3 w
Resistor,
Resistor, deposited carbon, 2&f, l%, l/2 w
deposited carbon, 400 ohm, I%, 1/2w R12-400
wirewound, 20 ohm, lo%,
composition, 100 ohm, lo%,
composition, 100 ohm, lo%, l/2 w
wirewound, lOK, lo%, 10 w
composition, 470 ohm, l%, 2 w
composition, 100 ohm, lo%, l/2 w
composition,
wirewound, lOK, lo%, 10 w
composition, 8.2K, lo%, 2 w
deposited carbon, 3,33M, l%, l/2 w R12-3.33M
composition, 750K, 5%, l/2 w
deposited carbon, 2M, l%, l/2 w
deposited carbon, 680K, 19, l/2 w
deposited carbon, 700K, l%, l/2 w
lK, 10% 1 w
3
w
l/2 w Rl-100
R12-22OK
R80-20
Rl-100
RS-10K
R3-470
Rl-100
R2-1K
RS-10K
R3-8.2K
R19-750K
R12-2M
R12-680K
R12-2M
RP15-100K
R12-700K
R12-2M
6-7
REPLACEABLE PARTS LIST
Circuit
Desin.
Description
MODEL 610A
Part No,
RF301
RF302
RF303
RF304
RF305
RF306
RF307
RF308
RF309
RF310
SW1
SW2
SW3
SW4
SW5
SW6
SW7
Rectifier, selenium, 13OV, 65Ma
Rectifier, selenium, 13OV, 65Ma
Rectifier, selenium, 13OV, 65Ma
Rectifier, selenium, 13OV, 65Ma
RF18
RF18
RF18
RF18
Rectifier, selenium, 13OV, 65Ma RF18
Rectifier, selenium, 13OV, 65Ma
Rectifier, selenium, 13OV, 65Ma
Rectifier, selenium, 13OV, 65Ma
RF18
RF18
RF18
Rectifier, selenium, 13OV, 65Ma RF18
Rectifier, selenium, 13OV, 65Ma RF18
Range switch 23 position
Slide switch, SPDT
Operate switch, 3 position
SW-46
SW-45
W-67-A
Coarse-balance switch, 7 position SW-93
Volt switch 9 position
Slide switch, DPDT
Meter switch, 5 position
Power transformer, (Model 610A)
SW-48
SIV-45
SW-64
TR-23
Power Transformer, (Model 610~) TR-57
Pilot Lamps 6.3 v, 0.15 amp. miniature bayonet
base G, E. type ff47
PL-4
:i
v5
V6
;;
v9
VlO
Vll
Vacuum tube, type 5886"
Vacuum tube, type 5886"
EV-5886-5
EV-5886-S
Vacuum tube, type EF86 EV-EF86
Vacuum tube, type EF86
Vacuum tube, type 6BH8
Vacuum tube, type 12AX7
Vacuum tube, type 12AX7
Vacuum tube, type 12B4A
Vacuum tube, type OB2
EV-EF86
EV-6BH8
EV-12AX7
EV-12AX7
EV-12B4A
EV-OB2
Vacuum tube, type OG3 EV-OG3
Vacuum tube, type OA2 EV-OA2
*Vl and V2 are matched tubes, and should be ordered
from Keithley Instruments as "EV-5886 matched tubes
for Model 610A Electrometer".
circuit
Deal&
--
R~AXADLE ~IHTS LIST - MODS 610~
--. -_-__.
---
Deocriptlon
Part
No.
Rx56
a57
R158
R159
~160
RI.61
1x162
R163
Rl5L
~165
RI66
R367
Resistor, deposited carbon, 800~, l%, ~$W
Potentiometer, carbon, 5OOK, 10%
Same as R131
Resistor, deposited carbon, 70X, l%, +)W
Potentiometer, wirewound, 5X
Resistor, deposited carbon, Ls.sK, 15, ?JW
Resistor, deposited carbon, 136X, l%, &W
Resistor, deposited aarbon, 319K, Id, AW
Resistor, deposited carbon,
6K, l$, 4%'
Resistor, deposited carbon, 7X, 18, $W
Resistor, deposited carbon, 2X, 15, $W
Resistor, deposited carbon, 700 ohm,
l%, %W
R12-800K
RP7-3
R12-70K
RP3-GK
Rl245.5x
R12-136X
R12-319K
R12-6K
Rl2-7K
R12-2X‘
R12-700
R168
RI69
RI.70
R171
R172
R173
R171r
R175
it176
R177
~178
R179
R180
Same as RlhO
Resistor, deposited carbon, 70 bhm, l%, 4W
Resistor, deposited carbon, 20 ohm, l%, &W
Resistor, deposited carbon, 10 ohm, l%, #'
Resistor, composition, 1X, 10%. $W,
Resistor, composition, 2.'2K, lO%, #'
Resistor, composition, L.7K, lo%, $W
Resistor, composition, lOK, lo%, &VI
Resistor, composition, 33K. lo%, #
Same as R105
Resistor, deposited carbon, 3K, I%, $W
Same as R121
Potentiometer. 10X
R12-70
R12-20
R12+7
Rl-1X
Rl-2.2K
Rl-b.7X
Rl-1OK
Rl-33K
R12-3K
RPL-10X
R181
Resistor, deposited carbon, 220X, l%, ;W
R12-220X
Circuit
Desig.
--
rwLAcEAnLE
-_--.-_--_-_--_-_
_---__~-_-__--__---_
PAHTS LIST - MODEL 610~
-
Dascription
I_____
Part,
No.
I_-.--_-.-
R182
R301
~302
R3O3
R3ob
R305
R306
R3O7
R308
RN?
R310
R311
Resistor, deposited carbon, LOO ohm, l$, $W
Resistor, composition, I.00 ohm, lo%, ;W
Same as R301
Resistor, wircwound, lo!<, lo%, 1OW
Resistor, composition, L70 ohm, 175, 2 T1a'c.t
Same as RjOl
Resistor, composition, lK, lOK, 1N
Resistor, wirewound, lOK, lo%, 1OW
Resistor, composition, 0.2K, lo%, 2W
Resistor, deposited carbon, 3.33M, l%, $V
ResIstor, composition, 750K, 55, ~$W
Iknl.stor, deposited carbon, 2M, l%, $V
RlZ-I~00
Rl-100
R!i'-1OK
R3470
R2-1K
R5-10K
R3-8.2K
Rl2-3.33M
R19-750K
R12-2M
~312
R313
R3lI
R315
R316
~~301,
RF303,
Resistor, deposited carbon, 680K, l%, +I
Same as R311
Potentiomater, carbon, lOOK, 371
Resistor,
&posited cu-bon, 700K, 1%, &V
Same cs H3ll
2 Rectifier, selenium, 130r!, 65~a
IJ Snme 11s RF301, 2
RF305,6,7 Same as RF301, 2
JUTiO8,9,:0 Same as RF301., 2
SW 1
SW 2
SW 3
Range witch 23 positi,on
Slide swjtch, DI'DT
Operate
switch, 3 position
R12-680X
RP15'-1OOK
R12-700K
RF18
SW46
swll5
SW-67-A
Circuit
Desig.
--
R!JPLAClN3LJX Pn?'l.% LIST - I,iOIll:L 61012
Description
__-
Part No.
-__
SW 4
SW 5
SW 6
SW 7
Vl
v2
V3
v4
V5
V6
Coarse-balance switch, 7 position
Volt witch 9 position
Slide switch, DPIYT
Meter switch, 5 position
Power transfomer, Central Transformer Co., Kl-I27
Pilot Lamps 6.3 v, 0.15 oxnp. miniature bayonet base
G. II. type $47
Vacuum tube, tme 5%36++
Vacuum tube, type 58%*
Vacuum tube, type iv66
Vacuum tube, type EF86
Vacuum tube, type 6BH8
Vacuum tube, type l2PXi'
SW-g3
a-48
SW-45
SW-64
m-123
PL-4
m-5886-5
m-5886-5'
Or m-5886-6
hV-EF86
m-ma6
LW-6~110
xv-l2Ax7
v7
V8
v9
no
VU
Vacuum tube, type l2.AX7
Vmxwm tube, type l2B4A
Vacuum tube, type OB2
Vacuum tube, type OG3
Vacuum tube, type OA2
EV-l2AX7
Ev-l2B4A
EV-OB2
EV-OG3
EV-OK?
*Vl and V2 are matched tubes, and should be ordered from
Keithley Instruments as "XV-5806 matched ttix?s for Model 610~
Electrometer" . If matched ret shipped is ~~-5886-5 and
LT..5086-6, the EV-5886-6 tube should be uned in V2.
,-
I-
,
I
c
t
-7
I
t
i
Loading...