User guide

L1
L1
L1
Specifications liable to change without prior warning V 125 Issue 3 January/2002 M.C. Applies to V 125/2
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SCALING
Two resistors Ra and Rb
may be used to alter the
full scale reading (FSR) of
the meter - see table. The
meter will have to be re-
calibrated by adjusting the
calibration potentiometer
on the rear of the module.
+
-
Ra
Rb
INHI
Vin or inI
INLO
FSR Ra Rb
2V 910k 100k
20V 1M 10k
Vin 200V 1M 1k
2000V* 1M 100R
200 A 0R 1k
2mA 0R 100R
Iin 20mA 0R 10R
200mA 0R 1R
µ
Voltage
Current
*Ensure that Ra is rated for high voltage use.
APPLICATIONS
Do not connect more than one meter to the same power supply
if the meters cannot use the same signal ground. Taking any
input beyond the power supply rails will damage the meter.
V 125 3½ Digit LCD Voltmeter Module
Normally
SHORTED
Cut to
OPEN
Normally
OPEN
Solder to
SHORT
0V 0V
+7.0 to +12V +7.0 to +12V
+3.5 to +6.0V
-3.5 to -6.0V
V+
V+
V+
IN HI
IN HI
IN HI
IN LO
IN LO
IN LO
11
33
22
V 125
V 125
V 125
V-
V-
V-
44
DP1 DP1
XDP XDP
66
5
1
3
2
4
DP1
XDP
6
5
5
±200mV
±200mV
+
+
I+
I-
-
-
Measuring an input voltage referenced to a floating supply,
i.e. the input voltage and the meter's power supply are
isolated from each other. Check Link L1 is closed.
Measuring a single ended input referenced to supply, i.e.
the input voltage and the meter's power supply share the
same 0V rail. Check Link L1 is open.
Measuring a current referenced to a floating supply, i.e. the
current being measured and the meter's power supply are
isolated from each other. Check Link L1 is closed.
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