Campbell Scientific TB4 and TB4MM Hydrological Services Rain Gage - Manual (Page 5)

TB4 and TB4MM Rain Gage
1. General Description
The TB4 and TB4MM tipping bucket rain gages are manufactured by
Hydrological Services Pty. Ltd. (Model TB4) and modified for use with
Campbell Scientific dataloggers.
These rain gages catch rainfall in the 7.87” (200 mm) diameter collection
funnel. When a full bucket of rainfall is collected, the tipping bucket assembly
tips and activates a reed switch. The switch closure is recorded by the
datalogger pulse channel. When the bucket tips, the water drains out the
screened fittings in the base of the gage.
Two models are available:
TB4 0.01 in. tip
TB4MM 0.2 mm tip
Throughout this manual, both models are referred to as the TB4
unless specified otherwise. NOTE
The “-L” after the model TB4 Rain Gage indicates that the cable length is
specified when ordering.
The TB4 ships with:
(1) Allen Wrench from Original Mfg.
(1) Resource CD
The 260-953 Alter-Type Wind Screen can be used with the TB4 and TB4MM
to minimize the effects of strong winds.
2. Specifications
Funnel: 7.87 in (200 mm)
Drain Fittings: Accept 12 mm ID tubing
Measurement Range: 0 to 19.7 in/hr
(0 to 500 mm/hr)
Accuracy: Better than +2% @ 19.7in/hr (500 mm/hr)
Resolution: 0.01 in (0.254 mm) TB4
0.2 mm (0.008 in) TB4MM
Environmental Conditions:
Temperature: 0° to +70°C
Humidity: 0 to 100%
Temperature Specifications: -20 to +70°C
Siphon Capacity: 0.012 in (0.3mm)
Contact: Dual Reed Switch
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