WAGNER L722 Owner's Manual

WAGNER MODEL L722

STACK PROBE

OWNER’S MANUAL

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Table of Contents

L722 STACK PROBE ATTACHMENT ..................................................................3

L722 SPECIFICATIONS .......................................................................................3

L722 CALIBRATION .............................................................................................3

L722 OPERATION ................................................................................................4

MAINTAINING ACCURACY OF MOISTURE CONTENT READINGS ..................4

L722 MAINTENANCE ...........................................................................................6

CLEANING ............................................................................................................6

SPRING REPLACEMENT ....................................................................................7

HINGE REPAIR/REPLACEMENT .........................................................................8

STORAGE ............................................................................................................8

COIL CORD REPLACEMENT ..............................................................................9

REPAIR SERVICE .............................................................................................. 11

REPLACEMENT PARTS .................................................................................... 13

WARNINGS ........................................................................................................ 15

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L722 STACK PROBE ATTACHMENT

The Model L722 Stack Probe attachment, coupled with the L612 or L622 (latest version) Digital Recording Moisture Meter makes it easy to reach deep into stickered units of lumber and take accurate moisture readings without the danger of broken pins. Wagner’s “Wood-Friendly” electromagnetic wave technology makes it possible to take multiple readings throughout an entire stack in just minutes.

NOTE: The L722 will work with either the L612 or the L622, for the remainder of this manual, the L622 will only be referenced.

Once the probe is inserted between the boards, the springs press the end-mounted sensor flat against the wood and ensure deep penetration of the electro-magnetic field. You then slide the probe slowly out of the stack, reading the moisture in each board as the sensor passes over it. Virtually unaffected by surface moisture, the L722 gives consistent and reliable readings in or out of kilns.

Patents 5,488,312 5,486,815 5,402,076

L722 SPECIFICATIONS

Overall Size Incl. Handle: L722L - L 48in x W 6.0in x H 1.625 in (121.9cm x 15.2cm x 4.12cm) L722 Probe Reach: L722 L722 Extrusion and Sensor Head: 0.5in (12.7mm) thickness Min/Max Sticker Range: 0.5in –0.9in (12.7mm – 22.9mm) Scanning Area: 2.5in x 2.5in (6.35cm x 6.35cm) Scanning Depth: 1.0in (2.54cm) minimum Shipping Weight: L722 L722

S - L34in x W 6.0in x H 1.625 in (86.3cm x 15.2cm x 4.12cm) L - L 40.5in (102.8cm) S - L 26.75in (67.9cm)

L - 128 oz. (3.64kg) S - 112 oz. (3.18kg)

L722 CALIBRATION

Calibration is factory set. Calibration may be checked by using the Calibration Verification Block (included with the L622), and following the instructions in the L622 Manual. The probe calibration is verified in the same manner as the L622 (Refer to the L622 Owner’s Manual).

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L722 OPERATION

To connect a probe to the L622, remove the dust plug from the beige-colored port labeled “PROBE” on the meter and plug the connecting cable into this port.

With the probe connected to the L622 and the meter ON, insert the probe into the sticker space between the layers of boards in a stack of lumber. The springs press the end-mounted sensor flat against the wood. The actual sensing area of the probe is located in the end of the probe assembly on the opposite side of the springs. Be sure to insert and remove the probe straight in and straight out of the stack of lumber to avoid damage to the L722 springs and hinge.

When the probe is connected to the meter, the internal hand-meter s ensor is bypassed and the probe will be the source of the readings. The backlight will also be turned on automatically for easier viewing in the dark kiln environment.

MAINTAINING ACCURACY OF MOISTURE CONTENT READINGS

The purpose of this section is to provide proper moisture content measurement techniques during kiln drying operations. The major factor of preserving consistent readings is to control the many variables that are present when moisture content (MC) values are measured. The control of these variables will be identified and addressed in the following paragraphs.

Taking L722 Stack Probe Measurements – The probe should be checked

for proper calibration prior to use. This can be accomplished by verifying the stack probe on the calibration block. The L622 meter should be checked for general operation and battery condition. Ensure the L622 meter has been selected for the appropriate wood species being measured. Verify a good connection with the coil cord at the meter by making sure the moisture content value doesn’t drift while wiggling the cable.

Consistent use of the stack probe will maintain the integrity of MC readings. Ensure the sensor plate area is completely covered by the lumber being measured. Take several measurements with the probe oriented along the length of the board, measure close to the “stickers” as wood surfaces will be more uniform at these locations.

Don’t pull down on the probe handl e beca us e hi ng e damag e may occur. The kiln drying operations procedure should spell out the specific number of

measurements to take, at what depth in the stack to measure, and when to measure them in the drying cycle. In order to main tai n cons i stency, take readings in the same locations in the stack, and at the same times in the drying cycle from one kiln charge

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to the next. You should take enough readings to be statistically significant. The more readings you take, the more accurate your “average” will be.

When taking measurements using a stack probe, you will be measuring the selected locations in the stack as stated in your kiln drying operations procedure. This will be the average moisture content of the scan area being measured directly under the sensor plate.

Keep in mind that the scan area of the L722 stack probe is 2.5” square (6.35cm) by 1” deep (2.54cm). This varies greatly from an in-line system, which has a much wider scan area (up to 12” square, 30.5cm), and deeper penetration. This will cause a larger area to be “averaged” with an in-line sy stem.

The L722 stack probe readings will read excessively high when measuring severely knotted lumber due to higher density. Readings will be best when measured on a clear, flat area on the wi de face of the lumber that is free of defects. If there is noticeable surface moisture, try not to measure at that spot until the moisture dissipates, or skip the area completely. As the moisture disperses, the effect will be minimized.

Kiln Drying, Moisture Gr a dients, and Temperature – Warm lumber tends

to lose moisture after it is removed from the kiln and it continues to dry. It can also absorb moisture from the air in hu mid condi tions during storage prior to planing. The moisture content of kiln-dried lumber is typically higher in the center core and dryer towards the ends and outer surfaces. Planing the dryer top and bottom sections of a board will cause the MC value to be higher. Because it is difficult to control all of these elements, it is best to try to maintain consistency in storage, and apply a correction factor as discussed in the paragraph below.

Frozen lumber can affect the MC readings. Wagner Meters has found that i f frozen lumber has a moisture content value lower than 15%, the readings are accurate. If the MC is higher than 15%, the actual reading obtained may be lower than the true value.

In a good measurement process consistency, repeatability, and correlation are the key factors. The goal is a better FINAL lumber product that meets your moisture content and grade goals. The closer your final product is to your target MC, the more cost efficient your drying process will be.

Here are some questions to ask yourself: Are all of your personnel taking the same number of readings? Are the readings being taken at the same time in the kiln dry schedule? Has my meter calibration been recently verified? Are the readings being taken at the same location in the same packs every time? This is the key to repeatability!

Applying Correction Fact ors - Due to variances beyond the c ontr ol of the

user, the MC values obtained from kiln dried lumber as read from th e Han d Meter

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WAGNER L722 Owner's Manual

Specifications and Main Features

Frequently Asked Questions

User Manual