EML ARG100 User Manual - page 8
UM-780-400-SBS Manual – V2.00
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P a g e
Paving slab method of levelling
1. Drill slab to suit studs
2. Drill out three holes in the rain gauge base to suit studs and deburr
3. Assemble all as shown in Figure 2
4. Position on ground and level carefully
Figure 2 - Paving slab method of levelling the rain gauge
Levelling the rain gauge using a spirit level
The gauge must be levelled for correct operation, and it is important to ensure that the rim of the rain
gauge is levelled precisely, using a spirit level; failure to do this will result in a systematic error.
Levelling is one of the simplest means of improving accuracy of rainfall measurements. Although a
small circular spirit level is provided in the base of the rain gauge, this is provided only as a quick check
system, always level the rim of the funnel precisely and check regularly.
Alternative mounting options
It is not always possible to mount a rain gauge on the ground surface. Examples of applications which
make use of rain gauges mounted above the ground include; urban monitoring, areas prone to
ground-flooding and areas prone to snowfall. It should be noted that regardless of which option is
used to mount the gauge, it must be firmly fixed and not susceptible to vibration. Vibration may lead
to ‘false-tipping’ of the bucket mechanism and thus contribute to erroneous or inaccurate
measurements. There are options which can be used to mount the ARG100 above the ground. The
ARG100 can be purchased with a rain gauge pedestal and guy kit or a rain gauge pedestal only.