Martel Electronics EM32-1B-LED - Manual (Page 4)

4 Martel Electronics Corporation EM32-1B-LED
Page 4 of 4
SCALING
Two resistors Ra and Rb may be
used to alter the full scale reading
(FSR) of the meter - see table. Cut
the PCB track across Ra before
fitting Ra. The meter will have to
be re-calibrated by adjusting the
calibration potentiometer on the
rear of the module.
+
-
Ra
Rb
IHI
Vin or in I
ILO
EM32-1B-LED
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
m
Voltage
Current
*Ensure that Ra is rated for high voltage use.
Must use external scaling resistors (Do not cut track across Ra).
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.
EM32-1B-LED
Round Hole Mounting LED Voltmeter
IHI
0V
0V
+
V+
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 Jumper link J1 is not fitted.
Ensure Jumper link J2 is fitted.
IHI
ILO
0V
0V
+
-
±200mV
+4.75 to +5.25V +4.75 to +5.25V
V+
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 Jumper link J1 is fitted.
Ensure Jumper link J2 is not fitted.
+4.75 to +5.25V
IHI
ILO
0V
0V
R
V+
Measuring current.
The meter's supply is isolated
from the current being measured.
Ensure Jumper link J1 is fitted.
Ensure Jumper link J2 is not fitted.
R = 0.2
I
FSR
RB
RA
Cut the PCB track across Ra
before fitting Ra.