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WindowEquivalentLayer model - Glass Visible Transmittance

asked 2018-11-25 07:22:48 -0500

updated 2020-01-15 11:38:00 -0500

Hi all,

I'm working with a model using the Construction:WindowEquivalentLayer object, as per this previous discussion. For some reason, I cannot adjust the parameters to get the Visible Light Transmittance of the whole window to be other than 0.

This may be something super simple, but I've been testing a bunch of options and parameters from the WindowGlazing Datasets, and all of them report a VLT of 0. Has someone run into something similar?

Many thanks in advance!

PS.Some screenshots of the model and report:

image description image description image description image description image description

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answered 2018-12-26 17:12:06 -0500

It's not clear in the documentation, but WindowEquivalentLayer does not work with daylighting. The reported VT of zero is accurate, even though it does not match the inputs. The solar properties cover the entire solar spectrum (including the visible range), so WindowEquivalentLayer fully accounts for solar gains and thermal conductance. But it does not do any visible range calculations to support daylighting.

Reference issue #5661.

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Asked: 2018-11-25 07:22:48 -0500

Seen: 299 times

Last updated: Dec 26 '18