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S A F E T Y I N F O R M A T I O N
Please follow the guidelines below, and read this manual in its entirety to
ensure safe operation of the unit.
Avoiding Damage to the Instrument - Precautions
The Instrument Case
Though the instrument is housed in a water-proof IP67 case, DO NOT use
it underwater. The cable connector is not waterproof unless the cap is
installed. In case of submersion without the cap connected, follow these
steps immediately:
1. Remove the battery and reinstall the battery cover.
2. Dry the connector if necessary, and replace the DO probe. Rinse unit
carefully with distilled water. After rinsing and drying, inspect and
clean connectors to remove all contaminants that may affect probe
connections.
3. Wait for unit and all connections to dry before reinstalling the battery
and resuming operation.
4. If the unit does not function correctly after step 3, contact YSI for
possible repair or replacement.
The Probe
1. Membranes last longer if properly installed and regularly maintained.
Erratic readings can result from damaged or fouled membranes or
from large bubbles in the electrolyte reservoir. If unstable readings
or membrane damage occurs, replace both the membrane cap
and Oxygen Probe solution (also known as “O2 Probe Electrolyte”,
potassium chloride, or KCl solution). The average replacement
interval is 4 to 8 weeks, although they may last longer if kept clean.
Harsh environments, such as wastewater, may require membrane
replacement every 2 to 4 weeks. Unstable readings may occur if
membrane cap is coated with oxygen consuming or oxygen evolving
organisms such as bacteria or algae.
2. Chlorine, sulfur dioxide, nitric oxide and nitrous oxide can affect
readings by behaving like oxygen at the probe.
3. Avoid substances that may damage probe materials such as
concentrated acid, caustics and strong solvents. Probe materials
include Stainless steel, epoxy and ABS Plastic.
4. Keep the probe’s gold cathode clean and textured (when properly
maintained it has a matte finish). If it is tarnished (from contact with
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