Veris Technologies MSP EC and pH (1997-2008 CF card drive 1.10M) - Operating Instructions - Manual (Page 37)

Veris Technologies
Pub. #OM MSP03-1
37
Maximum log time is the longest time in seconds the pH controller will wait for the pH readings to
settle. The controller usually cycles before this maximum time is reached. The minimum setting for
the maximum log time is 20 seconds. Press 1 or 2 to adjust the sample time, press 3 to continue to
the next screen.
Select the type of water you are using to clean the electrodes between samples. The available types
are TAP, RO (reverse osmosis), or DI (de-ionized). Press 1 or 2 to cycle through the water types,
press 3 to continue to the next screen.
Turning on the extra wash option will add 1.5 seconds of cleaning per cycle. The extra wash is
performed by stopping the shoe briefly during the cycle. Use this feature if you have noticed the
electrodes are not cleaning during the cycle. Press 1 or 2 to choose ON or OFF, press 3 to continue.
After all of the settings have been entered, the instrument will save the settings and return to the data
acquisition screen. You may continue collecting data using the new settings. Settings are stored in
memory and will remain as set until they changed.
pH Data Flags
Numbered “flags” can be added to the pH data by pressing the 2 key while the pH Manager is
CYCLING or RECORDING. If the key is pressed while the pH Manager is in the RECORDING
phase, an exclamation point (!) will appear on the screen next to the pH data labels:
This means the flag will be recorded with the current data point. If the key is pressed while
the pH Manager is in the CYCLING phase, the next point will be flagged and exclamation point
will not appear until the RECORDING phase is reached.
TIPS
As you collect pH data, monitor the performance of the system by observing the data you collect as
follows:
-Observe the pH data during the wash cycle to see that the electrodes are cleaning properly. If the
pH values during wash are not matching the expected pH of the wash water, or are not coming close
together, inspect wash system.
-Whenever the final pH readings at a sample location are >.75 apart, an alarm will sound indicating
data for that sample location will likely be eliminated during data extraction. If more than an
occasional, infrequent reading is rejected, inspect the sampler assembly for possible plugging or
other malfunction, and the electrodes for proper cleaning. Re-calibrate electrodes if necessary.
-The speed you travel and your transect width directly affects the sample density: 6 mph (9.6 km/hr)
on 50’ (15 m) transects provides approximately 10 samples/acre (24/ha). 10 mph (16 km/hr) on 60’
(18 m) transects results in approximately 5 samples/acre (12/ha). Collect enough samples so that the
raw pH data maps the underlying spatial structure of the field’s pH—rather than relying on
interpolation methods to fill in the gaps in the map.
(See laminated cab card for additional tips.)