Dpm 3as-bl, Applications, Scaling – Martel Electronics DPM 3AS-BL User Manual
Page 4: 3‰ digit backlit lcd voltmeter module, 5v supply operation, 9v supply operation, 0 to 7.5v meter power supply), 0 to 15.0v meter power supply)

DPM 3AS-BL
3‰ Digit Backlit LCD Voltmeter Module
Do not connect more than one meter to the same power supply if the meters cannot use the same signal
DPM 3AS-BL
Issue 4
December/2002
M.C.
Applies to DPM 3AS-BL/5
APPLICATIONS
ground. Taking any input beyond the power supply rails will damage the meter.
4
SCALING
Two external 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.
FSR
Ra
Rb
2V
910k
100k
20V
1M
10k
(Vin)
200V
1M
1k
2000V*
1M
100R
200 A
0R
1k
2mA
0R
100R
( in)
20mA
0R
10R
200mA
0R
1R
m
I
Voltage
Current
*Ensure that Ra is rated for high voltage use.
5V supply operation
(3.0 to 7.5V Meter Power Supply)
9V supply operation
(6.0 to 15.0V Meter Power Supply)
Measuring a single ended input
voltage referenced to supply, i.e. the
input voltage and the meter’s power
supply share the same 0V rail.
Ensure solder link LREF is closed.
Measuring a single ended input
voltage referenced to supply, i.e. the
input voltage and the meter’s power
supply share the same 0V rail.
Ensure solder link LREF is closed.
Measuring a current from a circuit which is
floating with respect to the DPM’s supply,
i.e. the current and the meter’s power
supply are isolated from each other.
Ensure solder link LREF is closed.
Measuring a current from a circuit which is
floating with respect to the DPM’s supply,
i.e. the current and the meter’s power
supply are isolated from each other.
Ensure solder link LREF is closed.
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.
Ensure solder link LREF is closed.
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.
+3.0 to +7.5V
7
Ensure solder link LREF is closed.
www.lascarelectronics.com
8
12
13
3
2
4
5
V+
INHI
INLO
COM
REF LO
+
GND
–200mV
-
0V
L-
L+
if V+>5V then
Rs=(V+ - 5V)
0.04
1M
10nF
+6.0 to +15.0V
1
8
12
13
3
2
4
5
V+
INHI
INLO
COM
REF LO
V-
+
–200mV
-
0V
L-
L+
Rs=(V+ - 5V)
0.04
1M
+3.0 to +7.5V
10nF
7
+6.0 to +15.0V
1
8
8
3
3
2
2
V+
V+
INHI
4
INHI
4
5
5
COM
COM
REF LO
REF LO
INLO
0V
INLO
GND
0V
V-
Rb
I
+
I-
+
I
Rb
I-
1M
1M
10nF
+3.0 to +7.5V
7
10nF
8
3
2
4
5
V+
INHI
INLO
COM
REF LO
+
GND
–200mV
-
0V
1M
10nF
+3.0 to +7.5V
1
-3.0 to -7.5V
8
3
2
4
5
V+
INHI
INLO
COM
REF LO
V-
+
–200mV
-
1M
10nF
+
-
Ra
1M
Rb
INHI
Vin or in
I
DPM 3AS-BL
INLO
10nF
Input Filter
PO Box 770, Londonderry, NH 03053 1-800-821-0023
www.martelcorp.com