Lab Grade. Accurate. Simple. Automated.
The Milwaukee MI455US PRO SO₂ Mini-Titrator is preferred by wine makers seeking results faster with lower costs and simple operation. The MI455US uses a piston-driven pump for accurate dynamic dosing, a built-in magnetic stirrer for a faster reaction and lab grade platinum-ringed ORP electrode. Using a modified Ripper method, this mini-titrator does not rely on color change but uses potentiometric detection. The MI455US automatically dispenses the titrant, determines the endpoint, and completes the calculations in a fraction of the time needed for a manual titration. The MI455US uses a preprogrammed method and specialized ORP electrode combined with an algorithm to determine the end of the titration reaction.

Summary
The Milwaukee MI455 PRO SO2 Mini-Titrator is preferred by wine makers seeking results faster with lower costs and simple operation.

The Milwaukee PRO SO2  PRO Mini-Titrator offers:

• Accuracy
  The MI455 PRO Mini-Titrator is accurate to 5% of the reading with a resolution of 1 ppm with a range of 0-400 ppm. The titrator uses piston-driven pump for accurate dynamic dosing, a built-in magnetic stirrer for a faster reaction and lab grade platinum-ringed ORP electrode.
   
• Simplicity
  The MI455 PRO Mini-Titrator is designed to for simple one button operation with pre-standardized titrant and pre-measured reagents for easy set up.
   
• Automated operation
  The MI455 PRO Mini-Titrator uses a precision piston style dosing pump that dynamically adjusts the dosing volume as the voltage changes. With the MI455 PRO Mini-Titrator, you get a faster result with no need for manual intervention or calculation.

Design Features

• Measure both free and total SO₂
• Easy measurement: just measure the wine sample, add the reagents as directed, prepare ORP probe and pump, add the stabilizer and start titration by pressing the start button.
• Refillable, double junction lab grade ORP electrode.
• 700 rpm built-in stirrer.
• Simple and reliable peristaltic pump that ensure high dosing repeatability.
• Compact 8.2 x 8.4” footprint.
• Built-in algorithm to analyze the shape of the electrode response and to determine the reaction completion that automatically completes the analysis, makes all necessary calculations and assures a user friendly interface.
• Replacement Reagent Kit:  Mi555-KIT.  Individual bottle here: Individual Reagent Bottles. 
• Replacement ORP Electrode:  MA924B/1.

Care and Use 
ORP electrodes usually start performing poorly because of problems with the probe. The two parts of the ORP probe that cause problems are the glass sensing bulb and the reference junction.

Sensing Bulb
The glass bulb loses sensitivity with use and will eventually fail. This is true of all ORP probes.

Reference Junction
The reference junction is a small hole that allows the meter to compare the sample to a reference. The reading is generated based on the electrical difference between the sample and reference. If the junction hole gets clogged, the ORP electrode will no longer function.

You can extend the life of your ORP electrode in the following ways.

Cleaning and Storage
All ORP sensors have a limited life and response time gets longer with age. Properly maintaining your ORP electrode will give you fast, accurate results for longer. So, be sure to order the Milwaukee Maintenance Kit code PH-Main at checkout time! This will be needed to help clean and condition the pH electrode before use!

Storage
To minimize clogging the ORP probe needs to be kept hydrated. Long periods of dry storage will damage the sensitivity of the probe. Allowing the probe to dry out may also result in the junction hole getting clogged.

Storing in ORP probe storage solution MA9015 will help address both these issues. Do not store in tap water or DI water. This will damage the sensitivity of the probe.

The best way to store the probe is with the probe's cap filled with storage solution and the cap tightened to prevent leakage. It is also recommended that to store the electrode upright to further reduce the potential for leakage.

Cleaning an Maintenance
Residue from the sample can impact the sensitivity of the sensing bulb and clog the junction. This is especially true if the sample has a lot of organic material. We recommend regularly soaking your electrode in cleaning solution MA9016. Also:

1. Inspect the electrode for damage or scratches, if present replace the electrode.

2. Inspect the cable.  The connection cable and insulation must be intact.

3. Connectors should be clean and dry.

4. Rinse off salt deposits with water or DI water.