IET Labs PRS-370 SERIES, Operation Manual

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PRS-370 Series
OPERATION 9
guide.
There are no user serviceable parts inside the
PRS-370. Servicing should be referred to qual-
i
fi ed personnel.
3.1.9 Cleaning
To prevent shock unplug the 1863 and 1864 from
mains prior to cleaning.
Use a dry cloth or a cloth slightly dampened with
water to clean the external case parts.
Do not use detergents or chemical solvents.
Do not attempt to clean internally.
Denatured alcohol can be used to clean insula-
tors around binding posts.
3.2 Connection
3.2.1 General Considerations
The PRS-370 Programmable Decade Resistance
Substituter utilizes a 5-terminal connection. The
binding posts are standard laboratory type and
readily accept banana plugs, spade lugs, alligator
clips, and bare wire. Binding posts are located on
the front panel and rear panel of the instrument.
The Kelvin terminals consisting of a CURRENT
and a SENSE pair, each labeled HI and LO .
These minimize contact resistance.
4 Wire connection
The gold shorting links must be removed on the
binding posts of the PRS-370 when set to 4 Wire.
2 Wire connection
The gold shorting links must be used on the
binding posts of the PRS-370 when set to 2 Wire.
See section 3.4.4 for more information
The GND terminal on all models is connected to
the case and to earth and chassis grounds. This
may be used as a shield terminal.
3.2.2 Electrical Considerations
The performance of the PRS-370 is directly
affected by the quality of the connection to
the system under test. This is particularly true
with the precision series models having higher-
accuracy and/or lower-impedance decades.
For optimum performance, contact resistance
should be kept to a minimum by using the most
substantial mating connection possible, and by
assuring that the connection is well secured to
the binding posts.
3.3 Condensed Operating Instructions
1. Turn on the PRS-370 ON using POWER
SWITCH
2. From the Home screen, select a desired
resistance value in one of the following ways:
a) Enter a value using the number keys, then
press
ENTER .
b) Press the resistance value shown on the
touch screen and then enter the resistance
value using the touch screen or keypad.
3. The source resistance will be output to the
front or rear binding posts and is indicated at on
the bottom half of the Home screen. Front and
rear binding posts can be selected by going to
Main Menu>Resistance Settings.
4. 2-Wire or 4-Wire connection mode is shown
at the top of the Home screen. This can be
changed by going to Main Menu>Resistance
Settings.