iET PRS-300 Series, Operation Manual

OPERATION

PRS-300 Series

8

Default values are: 

A

: 10 k

Ω

│

B

: 100 

k

Ω

c) Press 

RCL

 then a number key (

0 – 9

) 

to display a user-de

fi

 ned value or a fac-

tory default value. 
Default values are: 

0

 - 100 

Ω

│

1

 - 1 

k

Ω

│

2

 - 2 k

Ω

3.   

To prevent possible damage to 

the PRS-300, set the maximum 

applied voltage by pressing 

VOLT

, 

entering the voltage on the keypad, then 
pressing 

ENTER

. (Default: 0.5 V)

The 

fi

 rmware sets the minimum selectable 

resistance value so that the power does not 
exceed 1 W. To ensure that the whole range 
of resistances is selectable, 

VOLT 

setting 

must be 

≤

1 V.

Rmin is limited to >V

2

, where V is the 

VOLT setting.

4.  Select 2-wire or 4-wire mode by press-

ing the 

MENU

 button, selecting 

CON-

FIGURE

, pressing the “2” will  change 

between 2-wire and 4-wire modes  

In 2-wire mode shorting links must be in-

stalled across high and low terminal pairs.  

In 4-wire remove the shorting links.
5.  Connect to the circuit or device under test.

To isolate the PRS-300 from the application, 
press 

OPEN

 to open the circuit.  To close the 

circuit, press 

OPEN

 again.

3.4 Menu Structure

The main table below show menu struc-

ture of the PRS-300 and basic function of each 
button and menu selection.

Key

Description

Function

Basic operation

enter

enter button

Sets resistance value

0-9, 000/(-)

Used to enter numerical values. To select desired numerical 

value, press value as required.

(-)

 is used with tables for nega-

tive temperature

◄

Deletes the last character from 
the display.

To delete the last character, 
press 

◄

.

Options

MENU

Displays the following submenu:

1. STANDARD VALUES

1:  1% STD VALUES
2:  5% STD VALUES
3:  10% STD VALUES
4: RATIOMETRIC

2. CONFIGURE

1: LCD CONTRAST
2:  2W / 4W MODE

3. CALIBRATE
4. VERSION

Press 

MENU

 to select one of the 

following:

1.  STANDARD VALUES - se-

lects increments for UP 

and DOWN 

keys

2.  CONFIGURE - allows user 

to adjust display contrast 
and change between 2-wire 
and 4-wire modes

3.  CALIBRATE - see Section 8
4.  VERSION - Displays cur-

rent 

fi

 rmware version and 

release date.

INCR

Selects the increments for the 
UP 

 and DOWN 

 keys

Default value: Ratiometric (0.8% 
of displayed value)

To adjust increments:

1. Press 

INCR

.

2.  Enter desired increment 

value on the keypad.

3. Press 

ENTER 

to save.

Storing and recalling resistance values

STO

Stores a resistance value in 
memory locations A-D and 0-9.

To store a value, press 

STO

 and 

then press the desired location 
button A-D or 0-9.

A, B

Recalls a stored resistance 
value.
Default values:

A

: 10 k

Ω

B

: 100 k

Ω

To change stored values:

1.  Enter a resistance value
2. Press 

STO

 and then 

A

, 

B

RCL

Recalls a stored resistance 
value from memory location 0-9.

To recall a stored value, press 

RCL

, then press the desired 

location button (0-9)

Limiting Current

VOLT

Sets voltage to limit the current 
in order to protect the PRS-300 
from possible damage.
Default value: 0.5 V

To adjust voltage:

1. Press 

VOLT

.

2.  Enter desired voltage on the 

keypad.

3. Press 

ENTER 

to save.

Electrical Isolation

OPEN

Isolates the connection terminals 
by establishing an open circuit.

To open the circuit, press 

OPEN

.

To close, press 

OPEN

 again.

Option: Simulating RTD’s and transducers

TABLE

Loads up to 9 stored data 
tables for simulating RTD’s or 
transducers.

To select the desired table, 
press 

TABLE

 to cycle through 

the three options.