Veris Technologies pH Manager - Operating Instructions - Manual (Page 19)

Pub.# OM17-MSP-pH
3-11
After #4 key is pressed during Data Acquisition, the following screen will be displayed: (if data
was collected during Data Acquisition)
Figure 34
DATA IS ONLY STORED ON THE SD CARD. NO INTERNAL FILES ARE CREATED.
If no data was logged during Data Acquisition, the following screen will be displayed:
Figure 35
DATA QUALITY TIPS
As you collect pH data, monitor the performance of the system by continually asking yourself these
questions:
-
During ‘Cycling’ phase, do both pH electrode readings get close to the wash water pH? If not, one
or both electrodes may not be cleaning properly.
-
During ‘Recording’ phase, do both electrode readings move to expected soil pH level? If they stay
near wash pH level and/or require more than 10 seconds to settle, one of the following may have
occurred: 1) shoe may have plugged, so no new soil is entering, and the shoe is slowly filling up
with wash water; 2) Excessive speed may have allowed soil core to shoot out the back, or 3) gap
between electrodes and shoe may be excessive, so thinner soil cores aren’t contacting pH
electrodes.
-Operators who moni
tor the screen, and are alert to pH values that aren’t appropriate for the
Cycling or Recording phase, generate better maps.
-Whenever the final pH readings at a sample location are >.50 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). 5 mph (16 km/hr)
on 75’ (23 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.