Hioki RM3542-50, Instruction Manual

Page: 30 / 234

2.2 Connecting Measurement Probes and Test Fixtures
24
Recommended measurement probe specifications
Example: JIS standard 3C-2V, 1.5D-2V MIL standard RG-58A/U
*. Teflon is a registered trademark of E. I. du Pont de Nemours and Company.
Making Your Own Measurement Probes
Conductor resistance 500 m
Ω
/m or less
Capacitance 150 pF/m or less
Cable dielectric material
Polyethylene (PE), Teflon
*
(TFE), Polyethylene foam (PEF)
Insulation resistance 10 G Ω or more
Connector insulating material
Teflon
*
(TFE), Polybutylene terephthalate (PBT)
Insulation resistance10 G
Ω
or more
Length 2 m or less
Wiring Diagram
Before Wiring
• Twist the H
POT
and L
POT
wires, and the H
CUR
and L
CUR
wires together.
If not twisted together, measurement values may be unstable and errors may occur when measuring with
low-power resistance, or low resistance values.
• See the block diagram (p. 14) for the internal circuit details.
• Probes and measuring objects should be shielded at BNC or GUARD jack potential.
• Measurement probe length: keep it within 2 m (with a conductor resistance of 500 m Ω /m or less).
Long cables are more susceptible to noise, and the measurement values may be unstable.
• Extensions should maintain the four-terminal structure. If the wiring is converted to a two-terminal
structure in wiring, the correct measurement may not be possible due to the effects of the wiring and
contact resistance.
• Cables and measuring objects should be shielded.
• After extending the measurement probes, verify that the operation and accuracy conform to the
"Measurement Specifications" (p.192).
• When cutting off the ends of the optional measurement probes, make sure that the H
CUR
, H
POT
,
L
POT
, and L
CUR
shield wires and core wires do not come into contact. Such contact will made accu-
rate measurement impossible.
When Extending the Measurement Probes
Observe the following when extending the measurement probes.