Changing funnels with a different size
The TE525 and TE525MM rain gages use the same tipping mechanism that is calibrated to tip with the same amount of water. Changing their funnel does not necessitate changing the tipping mechanism, but it does require changing the multiplier in the data logger program to match the funnel size. See Multipliers for rain measurement for the correct multiplier.
The TE525WS rain gage uses a different tipping mechanism that is calibrated differently than the TE525 or TE525MM. The tipping mechanism must be replaced to work with a TE525 or TE525MM funnel. Send the rain bucket into the Campbell Scientific repair department for modifications. Contact Campbell Scientific to obtain an RMA (see Assistance).