Campbell Scientific OBS500 Smart Turbidity Meter with ClearSensor Technology User Manual

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OBS500 Smart Turbidity Meter with ClearSensor™ Technology

Note that Edlog only allocates one input location for Instruction 105. Two

input locations are required—one for the pressure measurement and one for the

temperature measurement. The additional input location needs to be inserted

manually using the Input Location Editor. To get into the Input Location

Editor, select Edit/Input Labels or press the F5 key. Once in the Input Location

Editor, do the following steps:

1. Choose Edit/Insert Block.

2. After the Insert Block dialog box appears, type in a base name for the

input locations. Each input location will have the base name with an

underscore and a consecutive number.

3. In the Start Address field, type in the number of the first input location.

4. In the Number of InLocs field, type in 2 and select OK.

7.7 Operation in High Sediment Loads and Sandy Sediments

Sites with high sediment loads and large sand grains can be problematic for the

shutter and its motor. The recommendations provided in this section should

help reduce these problems.

Typically sites with high biological growth have relatively low

sediment loads.

1. Run the OBS500 in a normally open mode. For example, close then open

the wiper once every four hours. This reduces the wear on the motor

significantly, and save power. The interval can be adjusted over time.

Increase the interval if experiencing fouling. If the windows are staying

clean, slow it down even more. Example CRBasic programs are provided

M3! opens the wiper

M4!, M5!, or M6! perform measurements when the wiper is open

M7! closes the wiper

2. Clean the shutter assembly. The frequency that the shutter should be

cleaned depends on the sediment load and can vary from weeks to months

(step 3 can help you determine the required frequency for cleaning). Two

levels of cleaning should be done;

a. flush the wiper as it opens and closes with a stream of clean water, or

b. remove the wiper from the OBS500 by removing one screw and

follow the directions provided in Section 7.7.1, Wiper Removal

Procedure. Flush and clean.

3. Store the current used to open and close the slider. The open and close

SDI-12 instructions (M3! and M7!) output the current. Normally the

current is around 100 mA. As sand grits lodge in the groves, the resistance

to movement increases and the motor has to work harder. This increases

NOTE