4
Simplifying high-accuracy resistance measurement
Convenient wide range options
The RM3545 can perform resistance measurement with a 6.5-digit,
1,200,000-count display at a maximum resolution of 0.01 μΩ. It delivers
more than enough capabilities to be used in applications requiring high-
resolution resistance measurement, for example in testing inverter motor
windings.
High-resistance materials such as conductive sheets and conductive rub-
ber are often used in electronic components. The RM3545 can measure
resistance values of up to 1,200 MΩ. It also delivers maximum accuracy of
0.006%, enabling researchers to test state-of-the-art current sensing resis-
tors.
Overview of the RM3545
Measure from 0.00
μΩ
to 1200.0M
Ω
0.0
1μΩ
max. resolution, 0.006% basic accuracy
Max. measurable current of 1A
Overview of the RM3544
Measure from 0.000m
Ω
to 3.5000M
Ω
1μΩ
max. resolution, 0.02% basic accuracy
Max. measurable current of 300mA
As inverter-equipped power supply equipment uses increasingly high cur-
rents and frequencies, increasingly low-resistance and low-loss inductors
are being incorporated in their circuitry, prompting a need for the ability to
measure lower resistance levels with a high level of stability. With a resolu-
tion of 1 μΩ, the RM3544/RM3544
-01
satisfy these needs.
Electronic components make extensive use of high-resistance substrates
such as conductive sheets and rubber, and the RM3544/RM3544
-01
deliver
the ability to measure up to 3.5 MΩ.
Moreover, the instruments’ maximum accuracy of 0.02% allows them to be
used in testing current detectors with a precision of 0.1%.
Guaranteed accuracy with no warm up
or zero-adjustment
For the RM3545/RM3544, accuracy is guaranteed
*
immediately after
startup, without any warm up or zero-adjustment.
*
When performing measurement with the RM3545 in a temperature and humidity environ-
ment that satisfies the guaranteed accuracy conditions, an even higher level of accuracy
(full accuracy) is guaranteed.
Thermal EMF occurs at connections between different metals. This force
can affect measurement and, if large enough, introduce a measurement er-
ror. The RM3545’s offset voltage correction (OVC) function reduces the
effects of thermal EMF to enable more precise measurement.
Offset Voltage Compensation (OVC)
High-durability probes
HIOKI offers a line of probes designed
to accommodate the full range of mea-
surement targets. Flex resistance has
been dramatically improved (based on
HIOKI comparisons).
Leads (overall view)
Example lead tip profiles
RM3544
RM3545
RM3544
RM3545
RM3544
RM3545
RM3544
RM3545
RM3545
RM3544
RM3545
Temperature correction
Generally, the resistance of copper wiring changes with temperature by 0.4%
per degree Celsius. The RM3544/RM3545 provide a temperature correction
function to convert the observed resistance value Rt at the current tempera-
ture t to the resistance value Rt
0
at the reference temperature t
0
.
*Requires the Temperature Sensor Z2001 or a thermometer capable of
generating analog voltage output (an infrared thermometer or similar
instrument).
Correction
R
t
R
t
0
Resistance
value
t
0
t
Temperature
Types of temperature
input
RM3544: Temperature Sensor (Z2001)
RM3545: Temperature Sensor (Z2001), Analog voltage
input (from an infrared thermometer, etc.)
Reference temperature
setting range
-10.0 to 99.9 °C
Temperature coefficient
setting range
RM3544: -9,999 to 9,999ppm/°C
RM3545: -99,999 to 99,999ppm/°C
Standard features of the high-accuracy Resistance Meter RM3545 and RM3544
Measurement resistance range [Ω]
Integrate into automated
inspection systems
Manual testing
on production lines
