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2. Set switches S1 and S2, the coarse
scale adjustments, as shown below.
The location of these switches is
shown in Figure 2.
A = COUNTS/mA_____
SB4 closed
SB4 open
0 - 24
0 - 49
25 - 39
50 - 79
40 - 63
80 - 125
3. Calculate B, the offset counts, from
the equation B=Ɪc-iC/Ɪ -i. For most
applications, B can be negative or
positive.
Switches
Negative Offset
Positive Offset
Figure 2. Component Location
4. Set switches S3 and S4, the coarse
offset adjustments as shown below.
B=Offset (Counts)
-700 to -1000
-1000 to -1500
S1
S2
5. Apply
On
Off
terminals 1 (+) and 2 (-) to obtain a
Off
Off
meter display.
Off
On
6. Adjust the ZERO potentiometer
(Figure 2) until the display equals the
desired reading.
7. Set the loop current to 20 mA and
adjust the SCALE potentiometer until
S5
S6
the display equals the desired reading.
On
Off
8. Repeat steps 5 & 6 until meter
Off
On
displays the readings desired.
9. Step 8 completes the calibration.
However, the meter should be checked
at tow or three widely spaced inputs to
insure its proper functioning.
S3
0 to -700
On
Off
Off
4
mA current between
Sample Computation
Input
4mA
S4
20mA
Off
Off
On
Ɪ = 4mA; Ɪ = 20mA; c = 000; C = 100
100-0
A = ----------- = --------- = 6.25
20-4
counts/mA
(20 X 0) – (4 X 100)
B = ----------------------------- = -------
20
= -25 counts offset
The Table in step 2 shows that switch
S1 should be set to ON, and S2 should
be set to OFF. The Table in step 4
shows that switch S3 should be set to
ON and S4 should be set to OFF. The
table in step 3 shows that switch S5
should be ON and S6 should be OFF.
Specifications Subject to Change
Without Notice
Thank you for choosing Non-Linear
Systems.
Should
questions please call, email or visit our
website at nonlinearsystems.com.
Non-Linear Systems
Originator of the Digital Voltmeter
San Diego, CA
619-521-2161
sales@nonlinearsystems.com
Display
000
100
100
16
400
-
4
16
you
have
any
6-21
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