Myron L TechPro ARH1 Guide

NOTE: Please read these instructions thoroughly and carefully — Damage caused by improper installation
or mishandling will void the warranties of the instrument and the new sensor.
CAUTION: Moisture trapped in instrument will cause damage. Careful adherence to the following procedure will
signicantly reduce the potential for failure due to moisture contamination.
Enclosed with this new sensor is a new orange O-ring, and a moisture protective foam, install per instructions in III. 8. below.
While the instrument is open, we recommend you replace the battery with a 9V alkaline type. For clarity, this procedure is broken
down into four sections. Follow each section carefully to avoid damage. Refer to drawings on reverse as necessary.
I. Preparing and Opening Instrument Case.
 1. RemovepHprotectivecapfromsensorwell,shakeoutuidanddry sensor well thoroughly.
2. If the instrument is wet, dry it thoroughly before proceeding, paying particular attention to the bottom screw holes.
Ensure hands are clean and dry. Moisture will damage the electronics.
3. Turn instrument over and set on a clean, dry surface.
4. Using a Phillips screwdriver, remove the 4 bottom screws.
5. Open instrument carefully. While removing bottom case ensure sealing gasket does not stick to bottom, but stays
in top case groove. If gasket comes out, handle carefully and reinstall in top case groove.
Exercise extreme care not to allow any water to enter the open case.
II. Disconnecting and Removing Old pH Sensor.
1. Locate the cable connector and disconnect (unscrew using a 1/4 in. open-end wrench) cable from circuit board.
2. If you are right handed, hold the instrument in your left hand with the rounded end up, and locate the pH sensor
and locking tab. See drawings B & C.
3. Using your left thumb, press the locking tab away from the sensor or toward the circuit board (the tab need
only be moved approximately 1/16 in./1.5 mm).
4. While holding locking tab back, pull straight out on the cables and body of the sensor, wiggling slightly if
necessary. Once the sensor moves upwards, you may let go of the tab and pull the sensor completely out.
5. Remove the old ORANGE O-ring and wipe out all residue from the sensor well.
6. Thoroughly inspect and clean both top and bottom case (paying special attention to the case gasket,
screw wells and screws.)
III. Preparing and Installing New pH Sensor.
1. Install new ORANGE O-ring in sensor well. See drawing C.
Steps 2-4 should be performed AWAY from instrument.
2. Remove tape from around new sensor and protective boot. CAUTION:Protectivebootislledwithaconcentrated
saline storage solution that will cause damage if allowed to come in contact with internal components.
3. Twist while pulling to remove the protective boot.
4. Rinse sensor with clean water and dry thoroughly.
5. Install new O-rings that came with the replacement sensor.
6. You have 2 sets of O-rings, the black is for units with a serial number less than T4206346. The brown are for
units with a serial number equal to or greater than T4206346.
7. Place part of the O-ring in the O-ring channel.
8. Pull the O-ring over the sensor body until seated in the O-ring channel.
9. Repeat for the second O-ring.
10. Align sensor with case (it will only go in one way — see drawings B & C). Ensure both O-rings on sensor slide
evenly into sensor well. CAUTION: A damaged O-ring will allow water to leak into case.
11. Press sensor into sensor well until an audible snap is heard and locking tab is in place. See drawing C.
12. Reconnect the cable. Tighten securely.
13. Remove existing moisture protective foam (light colored) from the bottom case, peel backing from new moisture
protective foam, and install inside bottom case in same location.
IV. Closing Instrument Case
1. Align cable so that it will NOT obstruct or become pinched while reinstalling the bottom case.
2. Ensure the case gasket is installed in the groove of the top case.
3. Replace bottom, aligning it with the groove.
4. Install and start the 4 bottom screws.
5. Tighten screws evenly and securely. An effective seal cannot be insured unless screws are secure.
Uneven tightening will cause instrument to rock.
 6. TurninstrumentoverandllpHsensorwellwithMyronLpHSensorStorageSolution.If unavailable, use a pH 4
Buffer or a saturated solution of table salt and tap water.
7. Reinstall protective cap on pH sensor well.
Your Instrument is now ready for calibration and use. See Operation Manual or Bottom Label for calibration instructions.
RPGI r05-19
RPG pH SENSOR REPLACEMENT INSTRUCTIONS
2450 Impala Drive
Carlsbad, CA 92010-7226 USA
Tel: [phone]
Fax: [phone]
www.myronl.com
For TechPro™ ARH1, PH1 and TechPro II™ TPH1, TH1

Alignment Guide
pH
Green Cable
Locking Tab
pH Sensor Body
Connector
B
Sensor Well
Install ORANGE O-ring in Sensor Well before installing sensor
ARH1 Shown
Circuit Board
TOP VIEW
pH Glass Electrode
Sensor Body
Locking Tab
Reference
Junction
under
Glass Bulb
A
C
Connector
Sensor Body pH Cable - Green
ORANGE Sensor Well O-ring Seal
Locking Tab
Sensor Well
SIDE VIEW
Cut-Away
Alignment Guide
O-ring Seals (2)
To install, Press here First.
Then, Press here to Snap in place.
pH SENSOR
Model RPG
W
ater Quality Instrumentatio
n
Accuracy • Reliability • Simplicity
2450 Impala Drive Carlsbad, CA 92010-7226 USA Tel: [phone] Fax: [phone] www.myronl.com
r05-19