/
will require a longer wait. The Model
51036
Test Leads employ a capacitor
to reduce the effects of
60
cps pickup, which slows the response appreciably
when measuring reaiBtance8 above about 1Ol-l ohms. Somercsitance specifi-
cations require an "electrification time", which is the interval between
applying the test potential and reading the resistance. The ASTMpamphlet,
included in this Manual, discusseo this in detail. The electrification time
is measured from the time the Test-Charge-Discharge switch is moved from
Discharge to Charge.
k. After meaaming, return the Test-Charge-Discharge switch to Discharge.
The instrument is now ready for the next test specimen. With the switch in
the Discharge position, all testing conductor8 are at ground potential, 80
that specimens can be chcangedwithout danger of shock to the operator.
After the instrument has been connected, turned on, warmed up, cali-
brated, and the test voltage selected, the operating procedure for measur-
ing a number of resistances is very simple. Just connect the unknown to the
test clip8; turn the Test-Charge-Discharge switch to TEST; read the meter;
return the switch to DISCRARGE:and then change to a new unknown resistor.
1.
After the instrument ha8 been operating for about five minutes, it
should be realigned to eliminate the effects of warmup drift. After this
ha8 been done, no more calibrations should be necessary during the following
eight hour period.
m. To rebalance the amplifier, eet the Calibrate-Test Potential switch
to
5
volts, end the Test-Charge-Discharge switch to Discharge. Then adjust
the Amp. Bal. potentiometer,
reads 107. on the left side of the cabinet, 80 that
meter
This adjustment is required only every month or 80.
The operating procedure is the samefor test leads, fixtures, or the
Keithley 5101 or 5102 Adapters. A wide variety of specialized setups is
discussed in the Appendix.
Whendesigning special testing fixtures, leads, or electrodes, provision
must be madefor operating the relay in the Model 510 to remove the short
circuit at the input of the micro-microammeter. Pins 2 and 3 of the connector
carrying the cable from the unknown to the Model
510
input can be jumpered
in the connector, or a switch to connect them can be made a part of the
special fixture, following the design of the switch in the Modela 5101 and
5102 adapters.
Reading the Meter: Fig.
510-3
is an en1 rged
sketch of one decade of the meter scale. 8
10 end
109 are the major division marks. The integer8
between them are also marked, with the 5 line made
longer and heavier for quick identification. The
other decade8 are read in a similar manner.
III - 2
510
l/58
