12
MW190 Dissolved Oxygen & Temperature Bench Meter
6. GENERAL OPERATIONS
6.1. POWER CONNECTION & BATTERY MANAGEMENT
MW190
has a built-in rechargeable battery that provides up to 8 hours of use. The internal
battery recharges with the supplied 12 VDC adapter or while connected to a PC USB port
or standard 5V USB charger.
MW190
is equipped with Battery Error Prevention System (BEPS) feature, which turns the
meter off after 10 minutes of non-use (see Auto Off in SETUP OPTIONS section).
At power on, the instrument performs an auto-diagnostic test and all LCD segments are
displayed for a few seconds. Use
keys to check the battery percentage.
6.2. PROBE PREPARATION
DO probes shipped from Milwaukee Instruments are dry.
Before measurements membrane cap needs to be primed and the probe polarized.
Changing the membrane cap
1. For new probes, remove the red and black shipping cap.
2. Open the supplied membrane package and remove one o-ring and one membrane cap.
3. Soak the bottom 2½ cm (1”) of the sensor in
MA9071
electrolyte solution for 5 minutes.
4. Inspect the membrane cap. The membrane is thin and can not be repaired if damaged.
5. Position the o-ring. Prime the cap with electrolyte solution. Shake gently, discard and
refill with clean solution making sure to cover the o-ring.
6. Gently tap the side of the cap to remove trapped air bubbles. Do not tap on the
membrane directly as it may damage it.
7. With the sensor facing downward, slowly screw the cap upward and counter
clockwise. Some electrolyte will overflow.
8. Rinse the outer body of the probe and inspect the membrane for trapped gas bubbles.
The cathode area should be free of bubbles.
9. While the probe is not in use, put the protective plastic cap on.
Connecting the probe
MA845
is connected to the meter through a DIN connector. With the meter off:
y
Connect the probe to the DIN socket on the top of the meter.
y
Align the pins and key then push the plug into the socket. Tighten the threaded ring.
y
Mount the supplied metallic plate onto the meter. Tighten the screw to lock in place.
y
Mount the arm holder over the metallic pin from the plate.
y
Place the probe into the holder.
