Hioki RM3542-50, Instruction Manual

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1.1 Product Overview and Features
14
•
A constant current (determined by the measurement range) is applied between the H
CUR
and L
CUR
terminals while
voltage is measured between the H
POT
and L
POT
terminals. The resistance value is obtained by dividing the measured
voltage (B) by the constant current flow (A). (
A, B
)
•
The effects of a large offset voltage, such as from thermal emf, are reduced by reversing the current and measuring
twice in positive and negative directions (A). (
A
)
•
The constant current source (A) and voltmeter (B) circuit designs are largely unaffected by contact resistance. (
A, B
)
•
Faulty measurement values caused by unstable or chattering contact conditions can be eliminated by monitoring (C)
the detection voltage (B) waveform (voltage level monitor function). (
B, C
)
•
The voltmeter is provided with sufficient time for integration (the default setting is 0.3 ms) to achieve stable measure-
ments. (The integration time can be reduced to 0.1 ms to support higher speeds.) (
B
)
•
Before measuring, the Contact Improver circuit (D) optimizes the contact when the probes touch the DUT. (
D
)
•
Also, performing contact checking (E) before measuring can detect short circuits between the CUR and POT terminals
caused by a clogged probe tip (probe short-circuit detection function). (
E
)
•
When measurement starts, the contact check circuit (E) and constant current monitor (F) are activated to monitor for
faulty conditions while measuring. (
E, F
)
•
The dual CPU (C and G) design provides ultra-high-speed measurements and a fast system response. (
C, G
)
•
Protection from electrical noise is provided by the isolation between the Measurement and Control blocks (H). (
H
)
•
The 90 V to 264 V wide range switching power supply (I) can provide stable measurements even in poor power quality
environments. (
I
)
Block Diagram
A B
C
D
E
F
G
H
I
E
D