13
TESTING BALED SCRAP PAPER
Set the meter scale to BALED PAPER
. Attach an external electrode to the meter.
Push the external electrode
into the material being tested.
Take readings
as described above.
The level of accuracy of meter readings depends on a number of factors: similarity between the
material tested and samples on which the calibration was made; moisture distribution; and chemical
application or processing which may affect the electrical properties of the paper product.
The required electrode is the H-4 with a #830-series prod (25cm(10”) or 45cm(18”)). A sharp, steel
rod to open the hole for the prod may be helpful if the bale is very dense.
A few meter readings in a limited number of specific areas of a large mass can hardly be projected to
indicate an average moisture content of an entire bale. The readings can be very helpful in providing
an indication of the
overall moisture condition
inside the bale and to detect areas of excessive
moisture.
Meter readings may be used as an arbitrary guideline in determining whether or not to accept or reject
the material. Since checking the moisture condition of bales is performed when buying and selling, the
specific value of the meter readings remains an element to be agreed upon between buyer and seller.
Such an agreement should consider not only a specific “range” of readings, but the number and
location of where they are taken.
The following ranges can be used as a guideline and may help to interpret the readings:
Readings of 8%-12%, with environmental humidity up to 60% RH are usually considered
“dry”.
Readings from 12%-20% with environmental humidity up to 95% are usually considered
“acceptable” but should be taken with some reservation.
Readings of 20%-40% are considered “wet” and unacceptable.
NOTE: MC RANGE AND VALID READINGS
Readings below 5% or above 60% are displayed as LOW or HIGH, respectively. However, since the
resistance of the paper also depends on the scale and temperature of the paper, the meter may not
always be able to read down to 5%. For different scale and different paper temperatures, there is a
minimum %MC limit below that the meter cannot read. All readings below this “lowest limit” are
displayed as LOW, and are not stored. These readings are not considered valid readings and are not
used by the meter in any statistical calculations.