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Solutions Strategies and Innovations
Static Solutions Inc.
Static Solutions Inc. - Ohm - Stat RT - 1000 Information
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6.
When the button is released and the value continues to display will this wear down the battery ?
Answer
: No. Once the button is released the display is saved by a capacitor on the screen for a short time. No additional
power is used.
7.
Is the meter manufactured in America, England or the Far East ?
Answer:
The correct answer is America. Pride, quality, and quick delivery.
8.
If I take consecutive readings do I have to re-zero the meter.
Answer
: No. The meter is auto zeroing. There is no need to rezero.
9.
What is RTT, RTG, volume resistance, resistivity ,concentric ring and bottom of meter parallel resistivity probes.) ?
Answer
: RTT is resistance between two points. The values are in ohms. The procedure must conform
to EOS specifications. The humidity and temperature must be recorded. RTG is resistance between
ground and one point. The ground can be the common point ground which is on the mat or another
common ground connected to the wrist straps. Resistance is a better way to determine if the product
will work in actual usage, by actually duplicating the dissipation of static electricity from the worker
or product to the earth ground. Resistance, either surface or volume is a better incoming quality
control test since most of the products being tested is two layers and resistivity does not relate to two
layer mat products. In a two layer mat material the path to ground goes from the surface down to the
conductive layer across then up through the dissipative layer.
Volume resistance tests through the material layers –from the top through the bottom layer.
Resistivity is measured in ohms/square. The test are is usually a small square. The parallel probes on
the bottom measures ohms/square. The concentric ring or guarded electrode does the same but it
avoids stray readings around the ends of the probes and measure inside the two rings. To calculate
the resistivity from resistance multiply the resistance measurements by 10. The conversion factor of
10 is derived from the geometry of the electrode assembly.
10.
When is the concentric ring electrode used to measure the resistivity values.
Answer
: Because there was a possibility of the applied voltage (either 10 or 100 volts) going
around the parallel probes and giving an incorrect answer a concentric ring probe was developed
and explained in EOS/ESD-S11.11-1993 part 6.1.2. When the concentric ring probe is used a
multiplying factor of 10 must be used. Thus, one takes the reading in ohms (resistance) and
multiply by 10 in order to derive the desired correct answer in ohms/square. (resistivity).
Resistivity is usually perfomed as a quick quality control measurement for smaller dimensions.
Special miniature probes are available for really small limited space dimensions..
11.
When the battery gets low can I still use the meter ?
Answer
: Yes. The meter will display “low battery” if the battery gets low in power. But even in this situation
the meter will still perform and will still display accurate results. The meter has incorporated a “cut-out” level
in which the meter will stop functioning completely when the power level gets too low to maintain a constant
10 or 100 volts output. Yes, there will be power left in the battery due to a regulator to maintain this correct
level.