Nest Power Controller and Transformer Question

Old 02-11-23, 06:01 AM
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Nest Power Controller and Transformer Question

Hello. The post so far have been very helpfull. I want to install power connectors for my Nest Learning thermostats. I am concerned that my existing transformer will not have enough power to support three or more power connectors. Can I use either a plugin adaptor to power them or add a new transformer just for the thermostates. If I do either of these what is the best way to connect the Nest power controller to the two terminals on the transformer or two wires on the plug in adapter.

Last edited by PJmax; 02-11-23 at 02:28 PM. Reason: removed 2nd picture
Old 02-11-23, 02:36 PM
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Welcome to the forums.

I removed that second picture so as not to muddy the waters.

When you use two wire thermostats and connect to TT there is absolutely no polarity as you are only closing a switch. Now you are adding a third wire (nest adapter) and the TT polarity becomes very important.

This diagram show you what you need to do for that controller...

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