General setup Milwaukee MW500 ORP User Manual

Milwaukee Instruments
  • Description

User manual PDF MW500 negative ORP meter setup instructions





Smart ORP Meter

ISTMW500 01/10



RANGE: ±1000 mV


ACCURACY (@25°C):  ±5 mV


ORP ELECTRODE:  MA921B/1 (included)

ENVIRONMENT:  0 to 50°C, 95% RH max.

BATTERY TYPE: 9V alkaline (included)

BATTERY LIFE: approximately 300 hours of use

DIMENSIONS: 143 x 80 x 32 mm

WEIGHT: 220 g (with battery) meter only


M10000B: Electrode rinse solution, 20 mL sachet (25 pcs)

MA9015: Electrode storage solution, 220 mL bottle

MA9020: 200-275 mV ORP solution, 220 mL bottle

MA921B/1:  Platinum ORP electrode with 1 m cable



This instrument is warranted from all defects in materials and manufacturing for a period of two years from the date of purchase.

The electrode is warranted for a period of six months.

If during this period, the repair or replacement of parts is required, where the damage is not due to negligence or erroneous operation by the user, please return the parts to either dealer or our office and the repair will be effected free of charge.

Note: We reserve the right to modify the design, construction and appearance of our products without advance notice.




• The meter is supplied complete with a 9V battery. Slide off the battery compartment cover located on the back of the meter. Install the battery into the battery clip connector while observing polarity.

• Always remove the electrode protective cap before taking any measurement. If the electrode has been left dry, soak the tip in storage solution for a few minutes to reactivate it.

• Connect the ORP electrode to the BNC socket on the top of the meter.

• Immerse the tip (2.5 cm) of the ORP electrode into the sample.

• Turn the instrument on by pressing the ON/OFF key.

• Allow the reading to stabilize before taking measurements.

• After use, switch the meter off and store the electrode with a few drops of storage

solution in the protective cap.

• The meter is factory calibrated. ORP electrodes are interchangeable and no mV calibration is needed when they are replaced.


• The surface of the ORP electrode must always be clean. Use M10000B rinse solution for this purpose. If needed, clean the Platinum tip with very fine abrasive paper.

• When not in use, the tip (reference junction) of the electrode should always be kept moist and safe from any mechanical stress.


When the battery becomes weak the meter will display "", the low battery indicator. The battery has about 50 hours of working time left. A low battery will result in unreliable measurements. Prompt battery replacement is required. Battery replacement must only take place in a non hazardous

area using an alkaline 9V battery. Turn the meter off, slide the battery compartment cover located

at the rear of the meter off and replace the 9V battery with a new one. Make sure the battery contacts are fully engaged in the connector, seat the battery in its compartment and replace the cover.

Related Products