Hach 900 MAX manual 5.4Dissolved Oxygen Probe, Dissolved Oxygen Probe Connection, Section

Section 5

4.Attach the positive battery terminal to the terminal block screw labeled “glass” and the negative battery terminal to the terminal block screw labeled “ref.”

5.After making all connections, measure the exact voltage on the “C” cell or power supply with a voltmeter. Then press a key to continue. The sampler displays the message “Waiting for ORP to Stabilize.”

6.Once the reading is sufficiently stable enter a new millivolt level. The “C” cell battery should be approximately 1500 mV (or 1.5 V) when new. Enter the exact voltage of the current source in millivolts.

7.Press ACCEPT to store the new calibration values.

8.Disconnect the “C” cell battery or regulated power supply from the ORP input terminals.

9.Reconnect the ORP Probe leads to the input terminals.

5.4Dissolved Oxygen Probe

5.4.1 Dissolved Oxygen Probe Connection

This connection is for interfacing the optional D.O. probe to the

D.O./Conductivity Pre-Amp (Cat. No. 3369).

Table 10 D.O. Connections (J20)

Pin	Signal Description	Wire Color
A	DO - (neg)	Green
B	DO + (pos)	Red
C	Thermister	Black
D	Thermister	Yellow

Strain Relief Recommendation

A strain relief is recommended to protect the cable/probe junction during application where the sensor will be thrown or tossed into liquid.

5.4.2 Dissolved Oxygen Probe Programming

Note: The membrane thickness must be programmed into the

instrument. The instrument uses this information to determine if the sensor is generating a reasonable current. Failure to program this value may result in false error conditions

1.From the Main Menu, select OPTIONS>ADVANCED OPTIONS>DATALOG.

2.Highlight Select Inputs using the UP and DOWN keys and press SELECT.

3.Highlight D.O. using the UP and DOWN keys, then press SELECT.

4.Press CHANGE CHOICE to cycle between Logged and Not Logged, then press ACCEPT.

5.Enter a logging interval, then press ACCEPT. Valid logging intervals are shown on the status bar.

6.Press CHANGE CHOICE to select the appropriate units (ppm, ppb, mg/L, sat). Press ACCEPT to continue.

7.Select another channel to configure, press RETURN to back up one step or press MAIN MENU to return to the Main Menu.

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Dissolved Oxygen Probe	8990options.fm